US20150353639A1 - Methods for improving safety of blood-brain barrier transport - Google Patents

Methods for improving safety of blood-brain barrier transport Download PDF

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US20150353639A1
US20150353639A1 US14/761,895 US201314761895A US2015353639A1 US 20150353639 A1 US20150353639 A1 US 20150353639A1 US 201314761895 A US201314761895 A US 201314761895A US 2015353639 A1 US2015353639 A1 US 2015353639A1
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antibody
bbb
compound
tfr
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Ryan Jefferson Watts
Joy Yu Zuchero
Jessica Couch
Mark Dennis
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Genentech Inc
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Genentech Inc
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Definitions

  • the present invention relates to compositions and methods for improving the safety of blood-brain barrier receptor-mediated blood-brain barrier transport.
  • BBB blood-brain barrier
  • Monoclonal antibodies have vast therapeutic potential for treatment of neurological or central nervous system (CNS) diseases, but their passage into the brain is restricted by the blood-brain barrier (BBB).
  • BBB blood-brain barrier
  • Past studies have shown that a very small percentage (approximately 0.1%) of an IgG circulating in the bloodstream crosses through the BBB into the CNS (Felgenhauer, Klin. Wschr. 52: 1158-1164 (1974)), where the CNS concentration of the antibody may be insufficient to permit a robust effect.
  • the percentage of the antibody that distributes into the CNS could be improved by exploiting BBB receptors (ie, transferrin receptor, insulin receptor, low density lipoprotein receptor-related protein 8, glucose transporter 1 (Glut1) and the like) (see, e.g., WO9502421).
  • BBB receptors ie, transferrin receptor, insulin receptor, low density lipoprotein receptor-related protein 8, glucose transporter 1 (Glut1) and the like
  • the anti-BBB receptor antibody can be made multispecific to target one or more desired antigens in the CNS, or one or more heterologous molecules can be coupled to the anti-BBB receptor antibody; in either case, the anti-BBB receptor antibody can assist in delivering a therapeutic molecule into the CNS across the BBB.
  • BBB-R high affinity anti-BBB receptor
  • anti-TfR A anti-TfR A antibodies
  • the lower affinity of the antibody for the BBB-R is proposed to impair the ability of the antibody to return to the vascular side of the BBB via the BBB-R from the CNS side of the membrane because the overall affinity of the antibody for the BBB-R is low and the local concentration of the antibody on the CNS side of the BBB is non-saturating due to the rapid dispersal of the antibody into the CNS compartment.
  • the circulating antibody levels of the lower-affinity antibody are sustained at therapeutic levels for a longer period of time than the higher-affinity antibody, which consequently improves uptake of antibody in brain for a longer period of time. Furthermore, this improvement in both plasma and brain exposure may reduce the frequency of dosing in the clinic, which would have potential benefit not only for patient compliance and convenience but also in lessening any potential side effects or off-target effects of the antibody and/or of a therapeutic compound coupled thereto.
  • mice displayed a primary response of robust depletion of reticulocyte populations accompanied by rapid onset acute clinical symptoms, as described in the Examples. Further in vitro studies using a human erythroblast cell line and primary bone marrow cells treated with anti-human TfR antibodies demonstrated that a robust depletion of TfR-positive erythroid cells is also observable in human cellular systems (see, e.g., Example 7). Though the mice recovered from both the acute clinical symptoms and the decreased reticulocyte levels in due course, avoiding or otherwise mitigating this impact on reticulocytes is clearly desirable for an anti-TfR antibody to be able to be used safely as a therapeutic molecule.
  • the invention provides compositions and methods that greatly reduce or eliminate the unwanted reduction in the reticulocyte population upon anti-TfR administration while still enabling the enhanced BBB transport, increased CNS distribution and CNS retention provided by low-affinity anti-TfR antibodies administered at therapeutic concentrations.
  • the results described herein show that the primary response to anti-TfR administration (robust reticulocyte depletion and acute clinical signs) is driven in large part by the antibody-dependent cell-mediated cytotoxicity (ADCC) activity of the antibody, while the residual reticulocyte depletion effect is mediated by the complement pathway.
  • ADCC antibody-dependent cell-mediated cytotoxicity
  • the effector function of the anti-BBB-R antibody is reduced or eliminated in order to reduce or eliminate ADCC activity.
  • the affinity of the anti-BBB-R antibody for the BBB-R is further lessened such that interactions of the antibody with the reticulocyte population are less detrimental to that population.
  • a third approach is directed to reducing the amount of anti-BBB-R antibody that is present in the plasma to reduce exposure of the reticulocyte population to potentially detrimental concentrations of the antibody.
  • a fourth approach seeks to protect, stabilize and/or replenish reticulocyte populations such that any potential depletion of the reticulocyte population by administration of the anti-BBB-R antibody is avoided, lessened, or mitigated.
  • Effector function reduction or elimination may be accomplished by: (i) reduction or elimination of wild-type mammalian glycosylation of the antibody, (for example, by producing the antibody in an environment where such glycosylation cannot occur, by mutating one or more carbohydrate attachment points such that the antibody cannot be glycosylated, or by chemically or enzymatically removing one or more carbohydrates from the antibody after it has been glycosylated); (ii) by reduction or elimination of the Fc receptor-binding capability of the anti-BBB-R antibody (for example, by mutation of the Fc region, by deletion within the Fc region or elimination of the Fc region); or (iii) by utilization of an antibody isotype known to have minimal or no effector function (ie., including but not limited to IgG4).
  • Decreasing antibody complement activation may be accomplished by reduction or elimination of the C1q binding capability of the anti-BBB-R antibody (for example, by mutation of, deletion within or elimination of the Fc region, or by modifying the non-Fc portion of the anti-BBB-R antibody), or by otherwise suppressing activation or activity of the complement system (for example, by co-administering one or more complement pathway activation or complement pathway activity inhibitors).
  • Reducing the amount of anti-BBB-R antibody present in the plasma in order to reduce exposure of the reticulocyte population to potentially detrimental concentrations of the antibody may be accomplished in several ways.
  • One method is to simply decrease the amount of the antibody that is dosed, potentially while also increasing the frequency of the dosing, such that the maximal concentration in the plasma is lowered but a sufficient serum level is maintained for efficacy, while still below the threshold of the cell-depleting side effect.
  • Another method which may be combined with dosing modifications, is to select or engineer an anti-TfR antibody that has pH-sensitive binding to TfR such that it binds to cell surface TfR in the plasma at pH 7.4 with desirably low affinity as described herein, but upon internalization into an endosomal compartment, such binding to TfR is rapidly and significantly reduced at the relatively lower pH of that compartment (pH 5.5-6.0).
  • Such dissociation may protect the antibody from antigen-mediated clearance, or increase the amount of antibody that is either delivered to the CNS or recycled back across the BBB—in either case, the effective concentration of the antibody is increased relative to an anti-TfR antibody that does not comprise such pH sensitivity, without increasing the administered dose of the antibody.
  • Protecting, stabilizing and/or replenishing reticulocyte populations may be accomplished using pharmaceutical or physical methods.
  • at least one further therapeutic agent may be coadministered (simultaneously or sequentially) that mitigates negative side effects of the antibody on reticulocyte populations.
  • therapeutic agents include, but are not limited to, erythropoietin (EPO), iron supplements, vitamin C, folic acid, and vitamin B12.
  • EPO erythropoietin
  • iron supplements iron supplements
  • vitamin C folic acid
  • vitamin B12 vitamin B12.
  • Physical replacement of red blood cells ie, reticulocytes
  • transfusion with similar cells which may be from another individual of similar blood type or may have been previously extracted from the subject to whom the anti-BBB-R antibody is administered.
  • any combination of the foregoing methods may be employed to engineer an antibody (and/or dosage regimen for same) with the optimum balance between (i) the desirably low affinity for the BBB-R that will maximize transport of the antibody and any conjugated compounds into the CNS; (ii) the affinity of the conjugated compound (including as a nonlimiting example, a second or further antigen-binding specificity in the anti-TfR antibody) for its CNS antigen, since this is relevant to the amount of the compound that needs to be present in the CNS to have a therapeutic effect; (iii) the clearance rate of the anti-BBB-R antibody; and (iv) the impact on reticulocyte populations.
  • the reticulocyte-depleting effect recognized herein of anti-TfR antibody administration may be useful in the treatment of any disease or disorder where overproliferation of reticulocytes is problematic.
  • reticulocytes in congenital polycythemia or neoplastic polycythemia vera, raised red blood cell counts due to hyperproliferation of, e.g., reticulocytes, results in thickening of blood and concomitant physiological symptoms.
  • Administration of an anti-TfR antibody of the invention wherein at least partial effector function of the antibody was preserved would permit selective removal of immature reticulocyte populations without impacting normal transferrin transport into the CNS. Dosing of such an antibody could be modulated such that acute clinical symptoms could be minimized (ie, by dosing at a very low dose or at widely-spaced intervals), as well-understood in the art.
  • Anti-TfR/BACE1 and anti-TfR/Abeta are each promising and novel therapeutic candidates for the treatment of Alzheimer's disease. Furthermore, receptor mediated transport (RMT)-based bispecific targeting technology opens the door for a wide range of potential therapeutics for CNS diseases.
  • RMT receptor mediated transport
  • the invention provides methods of engineering BBB-penetrant therapeutics that greatly improve transport across the BBB and CNS distribution of the therapeutic without depletion of reticulocytes.
  • the invention provides a method of transporting a compound across the blood-brain barrier in a subject comprising exposing an antibody which binds with low affinity to a blood-brain barrier receptor (BBB-R) coupled to a compound to the blood-brain barrier such that the antibody transports the compound coupled thereto across the blood-brain barrier, wherein reduction of red blood cell levels in the subject upon antibody administration to the subject is decreased or eliminated.
  • BBB-R blood-brain barrier receptor
  • the BBB-R is selected from the group consisting of transferrin receptor (TfR), insulin receptor, insulin-like growth factor receptor (IGF receptor), low density lipoprotein receptor-related protein 8 (LRP8), low density lipoprotein receptor-related protein 1 (LRP1), glucose transporter 1 (Glut1) and heparin-binding epidermal growth factor-like growth factor (HB-EGF).
  • TfR transferrin receptor
  • IGF receptor insulin-like growth factor receptor
  • LRP8 low density lipoprotein receptor-related protein 8
  • LRP1 low density lipoprotein receptor-related protein 1
  • Glut1 glucose transporter 1
  • HB-EGF heparin-binding epidermal growth factor-like growth factor
  • the BBB-R is a human BBB-R.
  • the BBB-R is TfR.
  • the BBB-R is TfR, and the antibody does not inhibit TfR activity.
  • the BBB-R is TfR and the antibody does not inhibit the binding of TfR
  • the red blood cells are immature red blood cells.
  • the immature red blood cells are reticulocytes.
  • reduction of reticulocyte levels is accompanied by acute clinical symptoms.
  • the method further comprises the step of monitoring the subject for depletion of red blood cells.
  • one or more properties of the antibody have been modified to reduce the impact of the antibody on reticulocyte levels and/or reduce the severity or presence of acute clinical symptoms in the subject.
  • the affinity of the antibody for the BBB-R is modified, i.e., decreased.
  • the effector function of the antibody Fc region is modified.
  • the effector function has been reduced or eliminated relative to the effector function of a wild-type antibody of the same isotype.
  • the effector function is reduced or eliminated by reduction of glycosylation of the antibody.
  • the glycosylation of the antibody is reduced by production of the antibody in an environment that does not permit wild-type glycosylation.
  • the antibody is produced in a non-mammalian cell production system. In another such aspect, the antibody is produced synthetically. In another such aspect, the glycosylation of the antibody is reduced by removal of carbohydrate groups already present on the antibody. In another such aspect, the glycosylation of the antibody is reduced by modification of the antibody such that wild-type glycosylation does not occur. In another such aspect, the Fc region of the antibody comprises a mutation at position 297 such that the wild-type asparagine residue at that position is replaced with another amino acid that interferes with glycosylation at that position. In another aspect, the effector function is reduced or eliminated by modification of the antibody isotype to an isotype that naturally has reduced or eliminated effector function.
  • the Fc region is modified to reduce or eliminate effector function.
  • the effector function is reduced or eliminated by at least one modification of the Fc region.
  • the modification is a point mutation of the Fc region to impair binding to one or more Fc receptors selected from the following positions: 238, 239, 248, 249, 252, 254, 265, 268, 269, 270, 272, 278, 289, 292, 293, 294, 295, 296, 297, 298, 301, 303, 322, 324, 327, 329, 333, 335, 338, 340, 373, 376, 382, 388, 389, 414, 416, 419, 434, 435, 437, 438, and 439.
  • the modification is elimination of some or all of the Fc region.
  • the effector function is reduced or eliminated by deletion of all or a portion of the Fc region, or by engineering the antibody such that it does not include an Fc region competent for effector function.
  • the antibody is selected from a Fab or a single chain antibody.
  • the Fc region and/or the non-Fc region of the antibody is modified to reduce or eliminate activation of the complement pathway by the antibody.
  • the modification is a point mutation of the Fc region to impair binding to C1q selected from the following positions: 270, 322, 329, and 321.
  • the modification is elimination of some or all of the Fc region.
  • complement-triggering function is reduced or eliminated by deletion of all or a portion of the Fc region, or by engineering the antibody such that it does not include an Fc region that engages the complement pathway.
  • the antibody is selected from a Fab or a single chain antibody.
  • the non-Fc region of the antibody is modified to reduce or eliminate activation of the complement pathway by the antibody.
  • the modification is a point mutation of the CH1 region to impair binding to C3.
  • the point mutation is at position 132 (see, e.g., Vidarte et al., (2001) J. Biol. Chem. 276(41): 38217-38223).
  • the dose amount and/or frequency of administration of the antibody is modulated to reduce the concentration of the antibody to which the red blood cells are exposed.
  • the antibody is modified to comprise pH-sensitive binding to the BBB-R.
  • a further compound is administered in addition to the antibody and the coupled compound.
  • the further compound is responsible for or contributes to the lack of reduction of reticulocyte levels.
  • the further compound inhibits or prevents the activation or activity of the complement pathway (see, e.g., Mollnes and Kirschfink (2006) Molec. Immunol. 43:107-121).
  • the further compound protects reticulocytes from antibody-related depletion.
  • the further compound supports the growth, development, or reestablishment of reticulocytes.
  • the further compound is selected from erythropoietin (EPO), an iron supplement, vitamin C, folic acid and vitamin B12.
  • EPO erythropoietin
  • the further compound is red blood cells or reticulocytes from the same subject.
  • the further compound is red blood cells or reticulocytes from another subject.
  • the compound is a neurological disorder drug.
  • the compound is an imaging agent.
  • the compound is labeled.
  • the antibody is labeled.
  • the antibody does not impair the binding of the BBB-R to one or more of its native ligands.
  • the antibody specifically binds to TfR in such a manner that it does not inhibit binding of the TfR to transferrin.
  • the BBB is in a mammal.
  • the mammal is a human.
  • the mammal has a neurological disorder.
  • the neurological disorder is selected from the group consisting of Alzheimer's disease (AD), stroke, dementia, muscular dystrophy (MD), multiple sclerosis (MS), amyotrophic lateral sclerosis (ALS), cystic fibrosis, Angelman's syndrome, Liddle syndrome, Parkinson's disease, Pick's disease, Paget's disease, cancer, and traumatic brain injury.
  • the BBB is in a human.
  • the antibody has an IC50 for the BBB-R from about 1 nM to about 100 ⁇ M. In another such aspect, the IC50 is from about 5 nM to about 100 ⁇ M. In another such aspect, the IC50 is from about 50 nM to about 100 ⁇ M. In another such aspect, the IC50 is from about 100 nM to about 100 ⁇ M. In another aspect, the antibody has an affinity for the BBB-R from about 5 nM to about 50 ⁇ M. In another aspect, the antibody has an affinity for the BBB-R from about 30 nM to about 30 ⁇ M. In another such aspect, the antibody, when coupled to a compound, has an affinity for the BBB-R from about 30 nM to about 1 ⁇ M.
  • the antibody when coupled to a compound, has an affinity for the BBB-R from about 50 nM to about 1 ⁇ M.
  • the compound-coupled antibody specifically binds to TfR and has an affinity for TfR between those affinities observed for the anti-TfR A /BACE1 antibody and the anti-TfR E /BACE1 antibody.
  • the compound-coupled antibody specifically binds to TfR and has an affinity for TfR between those affinities observed for the anti-TfR D /BACE1 antibody and the anti-TfR E /BACE1 antibody.
  • the compound-coupled antibody specifically binds to TfR and has an IC50 for TfR between those IC50s observed for the anti-TfR A /BACE1 antibody and the anti-TfR E /BACE1 antibody. In another such aspect, the compound-coupled antibody specifically binds to TfR and has an IC50 for TfR between those IC50s observed for the anti-TfR D /BACE1 antibody and the anti-TfR E /BACE1 antibody. In one aspect, the affinity of the anti-BBB-R or anti-BBB-R/compound for the BBB-R is measured using scatchard analysis.
  • the affinity of the anti-BBB-R or anti-BBB-R/compound for the BBB-R is measured using BIACORE analysis. In another aspect, the affinity of the anti-BBB-R or anti-BBB-R/compound for the BBB-R is measured using a competition ELISA.
  • the dissociation half-life of the antibody from the BBB-R to which it specifically binds is from about 30 seconds to about 30 minutes. In another such aspect, the dissociation half-life is from about 30 seconds to about 20 minutes. In another such aspect, the dissociation half-life is from about 30 seconds to about 10 minutes. In another such aspect, the dissociation half-life is from about 30 seconds to about 5 minutes. In another such aspect, the dissociation half-life is from about 30 seconds to about 3 minutes. In another such aspect, the dissociation half-life is from about 30 seconds to about 2 minutes. In another such aspect, the dissociation half-life is about two minutes. In another such aspect, the dissociation half-life is one minute or less.
  • the compound-coupled antibody specifically binds to TfR and has a dissociation half-life for TfR between those dissociation half-lives observed for the anti-TfR A /BACE1 antibody and the anti-TfR E /BACE1 antibody from their respective binding to TfR.
  • the compound-coupled antibody specifically binds to TfR and has a dissociation half-life for TfR between those dissociation half-lives observed for the anti-TfR D /BACE1 antibody and the anti-TfR E /BACE1 antibody from their respective binding to TfR.
  • the dissociation half-life of the anti-BBB-R or anti-BBB-R/compound for the BBB-R is measured using BIACORE analysis. In another aspect, the dissociation half-life of the anti-BBB-R or anti-BBB-R/compound for the BBB-R is measured using a competition binding assay, such as a competition ELISA.
  • the compound-coupled antibody is administered at a therapeutic dose. In one such aspect, the therapeutic dose is a dose that saturates the BBB-R to which the antibody specifically binds. In another such aspect, the compound-coupled antibody is administered at a dose and dose frequency that minimizes red blood cell interaction with the compound-coupled antibody while still facilitating compound delivery across the BBB into the CNS at therapeutic levels.
  • the compound is covalently coupled to the antibody.
  • the compound is joined to the antibody by a linker.
  • the linker is cleavable.
  • the linker is not cleavable.
  • the compound is directly linked to the antibody.
  • the antibody is a multispecific antibody and the compound forms one portion of the multispecific antibody.
  • the multispecific antibody comprises a first antigen binding site which binds the BBB-R and a second antigen binding site which binds a brain antigen.
  • the brain antigen is selected from the group consisting of: beta-secretase 1 (BACE1), Abeta, epidermal growth factor receptor (EGFR), human epidermal growth factor receptor 2 (HER2), Tau, apolipoprotein E4 (ApoE4), alpha-synuclein, CD20, huntingtin, prion protein (PrP), leucine rich repeat kinase 2 (LRRK2), parkin, presenilin 1, presenilin 2, gamma secretase, death receptor 6 (DR6), amyloid precursor protein (APP), p75 neurotrophin receptor (p75NTR), interleukin 6 receptor (IL6R), TNF receptor 1 (TNFR1), interleukin 1 beta (IL1 ⁇ ), and caspase 6.
  • BACE1 beta-secretase 1
  • EGFR epidermal growth factor receptor
  • HER2 human epidermal growth factor receptor 2
  • Tau apolipoprotein E4
  • the multispecific antibody binds both TfR and BACE1. In another such aspect, the multispecific antibody binds both TfR and Abeta. In another such aspect, the multispecific antibody is labeled. In another aspect, the compound is reversibly coupled to the antibody such that the compound is released from the antibody concurrent with or after BBB transport.
  • the invention provides a method of increasing exposure of the CNS of a subject to a compound, wherein the compound is coupled to an antibody which binds with low affinity to a BBB-R, thereby increasing the exposure of the CNS to the compound, and wherein reduction of red blood cell levels in the subject upon compound-coupled antibody administration to the subject is decreased or eliminated.
  • the BBB-R is selected from the group consisting of transferrin receptor (TfR), insulin receptor, insulin-like growth factor receptor (IGF receptor), low density lipoprotein receptor-related protein 8 (LRP8), low density lipoprotein receptor-related protein 1 (LRP1), glucose transporter 1 (Glut1) and heparin-binding epidermal growth factor-like growth factor (HB-EGF).
  • the BBB-R is a human BBB-R. In one such aspect, the BBB-R is TfR. In another such aspect, the BBB-R is TfR, and the antibody does not inhibit TfR activity. In another such aspect, the BBB-R is TfR and the antibody does not inhibit the binding of TfR to transferrin.
  • the red blood cells are immature red blood cells.
  • the immature red blood cells are reticulocytes.
  • reduction of reticulocyte levels is accompanied by acute clinical symptoms.
  • the method further comprises the step of monitoring the subject for depletion of red blood cells.
  • one or more properties of the antibody have been modified to reduce the impact of the antibody on reticulocyte levels and/or reduce the severity or presence of acute clinical symptoms in the subject.
  • the affinity of the antibody for the BBB-R is modified, i.e., decreased.
  • the effector function of the antibody Fc region is modified.
  • the effector function has been reduced or eliminated relative to the effector function of a wild-type antibody of the same isotype.
  • the effector function is reduced or eliminated by reduction of glycosylation of the antibody.
  • the glycosylation of the antibody is reduced by production of the antibody in an environment that does not permit wild-type glycosylation.
  • the antibody is produced in a non-mammalian cell production system. In another such aspect, the antibody is produced synthetically. In another such aspect, the glycosylation of the antibody is reduced by removal of carbohydrate groups already present on the antibody. In another such aspect, the glycosylation of the antibody is reduced by modification of the antibody such that wild-type glycosylation does not occur. In another such aspect, the Fc region of the antibody comprises a mutation at position 297 such that the wild-type asparagine residue at that position is replaced with another amino acid that interferes with glycosylation at that position. In another aspect, the effector function is reduced or eliminated by modification of the antibody isotype to an isotype that naturally has reduced or eliminated effector function.
  • the Fc region is modified to reduce or eliminate effector function.
  • the effector function is reduced or eliminated by at least one modification of the Fc region.
  • the modification is a point mutation of the Fc region to impair binding to one or more Fc receptors selected from the following positions: 238, 239, 248, 249, 252, 254, 265, 268, 269, 270, 272, 278, 289, 292, 293, 294, 295, 296, 297, 298, 301, 303, 322, 324, 327, 329, 333, 335, 338, 340, 373, 376, 382, 388, 389, 414, 416, 419, 434, 435, 437, 438, and 439.
  • the modification is elimination of some or all of the Fc region.
  • the effector function is reduced or eliminated by deletion of all or a portion of the Fc region, or by engineering the antibody such that it does not include an Fc region competent for effector function.
  • the antibody is selected from a Fab or a single chain antibody.
  • the Fc region and/or the non-Fc region of the antibody is modified to reduce or eliminate activation of the complement pathway by the antibody.
  • the modification is a point mutation of the Fc region to impair binding to C1q selected from the following positions: 270, 322, 329, and 321.
  • the modification is elimination of some or all of the Fc region.
  • complement-triggering function is reduced or eliminated by deletion of all or a portion of the Fc region, or by engineering the antibody such that it does not include an Fc region that engages the complement pathway.
  • the antibody is selected from a Fab or a single chain antibody.
  • the non-Fc region of the antibody is modified to reduce or eliminate activation of the complement pathway by the antibody.
  • the modification is a point mutation of the CH1 region to impair binding to C3.
  • the point mutation is at position 132 (see, e.g., Vidarte et al., (2001) J. Biol. Chem. 276(41): 38217-38223).
  • the dose amount and/or frequency of administration of the antibody is modulated to reduce the concentration of the antibody to which the red blood cells are exposed.
  • the antibody is modified to comprise pH-sensitive binding to the BBB-R.
  • a further compound is administered in addition to the antibody and the coupled compound.
  • the further compound is responsible for or contributes to the lack of reduction of reticulocyte levels.
  • the further compound inhibits or prevents the activation or activity of the complement pathway (see, e.g., Mollnes and Kirschfink (2006) Molec. Immunol. 43:107-121).
  • the further compound protects reticulocytes from antibody-related depletion.
  • the further compound supports the growth, development, or reestablishment of reticulocytes.
  • the further compound is selected from erythropoietin (EPO), an iron supplement, vitamin C, folic acid and vitamin B12.
  • EPO erythropoietin
  • the further compound is red blood cells or reticulocytes from the same subject.
  • the further compound is red blood cells or reticulocytes from another subject.
  • the compound is a neurological disorder drug.
  • the compound is an imaging agent.
  • the compound is labeled.
  • the antibody is labeled.
  • the antibody does not impair the binding of the BBB-R to one or more of its native ligands.
  • the antibody specifically binds to TfR in such a manner that it does not inhibit binding of the TfR to transferrin.
  • the antibody-coupled compound is administered to a mammal.
  • the mammal is a human.
  • the mammal has a neurological disorder.
  • the neurological disorder is selected from the group consisting of Alzheimer's disease (AD), stroke, dementia, muscular dystrophy (MD), multiple sclerosis (MS), amyotrophic lateral sclerosis (ALS), cystic fibrosis, Angelman's syndrome, Liddle syndrome, Parkinson's disease, Pick's disease, Paget's disease, cancer, and traumatic brain injury.
  • AD Alzheimer's disease
  • MD muscular dystrophy
  • MS multiple sclerosis
  • ALS amyotrophic lateral sclerosis
  • cystic fibrosis Angelman's syndrome
  • Liddle syndrome Parkinson's disease
  • Parkinson's disease Pick's disease
  • Paget's disease cancer
  • traumatic brain injury traumatic brain injury
  • the increase in CNS exposure to the compound is measured relative to the CNS exposure of a compound coupled with a typical antibody not having lowered affinity for the BBB-R.
  • the increase in CNS exposure to the compound is measured as a ratio of the amount of the compound found in the CNS relative to the amount found in the serum after administration. In another such aspect, the increase in CNS exposure results in a ratio of greater than 0.1%.
  • the increase in CNS exposure to the compound is measured relative to the CNS exposure of a compound in the absence of a coupled antibody.
  • the increase in CNS exposure to the compound is measured by imaging.
  • the increase in CNS exposure to the compound is measured by an indirect readout such as a modification of one or more physiological symptoms.
  • the antibody has an IC50 for the BBB-R from about 1 nM to about 100 ⁇ M. In another such aspect, the IC50 is from about 5 nM to about 100 ⁇ M. In another such aspect, the IC50 is from about 50 nM to about 100 ⁇ M. In another such aspect, the IC50 is from about 100 nM to about 100 ⁇ M. In another aspect, the antibody has an affinity for the BBB-R from about 5 nM to about 50 ⁇ M. In another aspect, the antibody has an affinity for the BBB-R from about 30 nM to about 30 ⁇ M. In another such aspect, the antibody, when coupled to a compound, has an affinity for the BBB-R from about 30 nM to about 1 ⁇ M.
  • the antibody when coupled to a compound, has an affinity for the BBB-R from about 50 nM to about 1 ⁇ M.
  • the compound-coupled antibody specifically binds to TfR and has an affinity for TfR between those affinities observed for the anti-TfR A /BACE1 antibody and the anti-TfR E /BACE1 antibody.
  • the compound-coupled antibody specifically binds to TfR and has an affinity for TfR between those affinities observed for the anti-TfR D /BACE1 antibody and the anti-TfR E /BACE1 antibody.
  • the compound-coupled antibody specifically binds to TfR and has an IC50 for TfR between those IC50s observed for the anti-TfR A /BACE1 antibody and the anti-TfR E /BACE1 antibody. In another such aspect, the compound-coupled antibody specifically binds to TfR and has an IC50 for TfR between those IC50s observed for the anti-TfR D /BACE1 antibody and the anti-TfR E /BACE1 antibody. In one aspect, the affinity of the anti-BBB-R or anti-BBB-R/compound for the BBB-R is measured using scatchard analysis.
  • the affinity of the anti-BBB-R or anti-BBB-R/compound for the BBB-R is measured using BIACORE analysis. In another aspect, the affinity of the anti-BBB-R or anti-BBB-R/compound for the BBB-R is measured using a competition ELISA.
  • the dissociation half-life of the antibody from the BBB-R to which it specifically binds is from about 30 seconds to about 30 minutes. In another such aspect, the dissociation half-life is from about 30 seconds to about 20 minutes. In another such aspect, the dissociation half-life is from about 30 seconds to about 10 minutes. In another such aspect, the dissociation half-life is from about 30 seconds to about 5 minutes. In another such aspect, the dissociation half-life is from about 30 seconds to about 3 minutes. In another such aspect, the dissociation half-life is from about 30 seconds to about 2 minutes. In another such aspect, the dissociation half-life is about two minutes. In another such aspect, the dissociation half-life is one minute or less.
  • the compound-coupled antibody specifically binds to TfR and has a dissociation half-life for TfR between those dissociation half-lives observed for the anti-TfR A /BACE1 antibody and the anti-TfR E /BACE1 antibody from their respective binding to TfR.
  • the compound-coupled antibody specifically binds to TfR and has a dissociation half-life for TfR between those dissociation half-lives observed for the anti-TfR D /BACE1 antibody and the anti-TfR E /BACE1 antibody from their respective binding to TfR.
  • the dissociation half-life of the anti-BBB-R or anti-BBB-R/compound for the BBB-R is measured using BIACORE analysis. In another aspect, the dissociation half-life of the anti-BBB-R or anti-BBB-R/compound for the BBB-R is measured using a competition binding assay, such as a competition ELISA.
  • the compound-coupled antibody is administered at a therapeutic dose.
  • the therapeutic dose is a dose that saturates the BBB-R to which the antibody specifically binds.
  • the compound-coupled antibody is administered at a dose and dose frequency that minimizes red blood cell interaction with the compound-coupled antibody while still facilitating compound delivery across the BBB into the CNS at therapeutic levels.
  • the compound is covalently coupled to the antibody.
  • the compound is joined to the antibody by a linker.
  • the linker is cleavable.
  • the linker is not cleavable.
  • the compound is directly linked to the antibody.
  • the antibody is a multispecific antibody and the compound forms one portion of the multispecific antibody.
  • the multispecific antibody comprises a first antigen binding site which binds the BBB-R and a second antigen binding site which binds a brain antigen.
  • the brain antigen is selected from the group consisting of: beta-secretase 1 (BACE1), Abeta, epidermal growth factor receptor (EGFR), human epidermal growth factor receptor 2 (HER2), Tau, apolipoprotein E4 (ApoE4), alpha-synuclein, CD20, huntingtin, prion protein (PrP), leucine rich repeat kinase 2 (LRRK2), parkin, presenilin 1, presenilin 2, gamma secretase, death receptor 6 (DR6), amyloid precursor protein (APP), p75 neurotrophin receptor (p75NTR), interleukin 6 receptor (IL6R), TNF receptor 1 (TNFR1), interleukin 1 beta (IL1 ⁇ ), and caspase 6.
  • BACE1 beta-secretase 1
  • EGFR epidermal growth factor receptor
  • HER2 human epidermal growth factor receptor 2
  • Tau apolipoprotein E4
  • the multispecific antibody binds both TfR and BACE1. In another such aspect, the multispecific antibody binds both TfR and Abeta. In another such aspect, the multispecific antibody is labeled. In another aspect, the compound is reversibly coupled to the antibody such that the compound is released from the antibody concurrent with or after BBB transport.
  • the invention provides a method of decreasing clearance of a compound administered to a subject, wherein the compound is coupled to an antibody which binds with low affinity to a BBB-R, such that the clearance of the compound is decreased, and wherein reduction of red blood cell levels in the subject upon compound-coupled antibody administration to the subject is decreased or eliminated.
  • the BBB-R is selected from the group consisting of transferrin receptor (TfR), insulin receptor, insulin-like growth factor receptor (IGF receptor), low density lipoprotein receptor-related protein 8 (LRP8), low density lipoprotein receptor-related protein 1 (LRP1), glucose transporter 1 (Glut1) and heparin-binding epidermal growth factor-like growth factor (HB-EGF).
  • the BBB-R is a human BBB-R. In one such aspect, the BBB-R is TfR. In another such aspect, the BBB-R is TfR, and the antibody does not inhibit TfR activity. In another such aspect, the BBB-R is TfR and the antibody does not inhibit the binding of TfR to transferrin.
  • the red blood cells are immature red blood cells.
  • the immature red blood cells are reticulocytes.
  • reduction of reticulocyte levels is accompanied by acute clinical symptoms.
  • the method further comprises the step of monitoring the subject for depletion of red blood cells.
  • one or more properties of the antibody have been modified to reduce the impact of the antibody on reticulocyte levels and/or reduce the severity or presence of acute clinical symptoms in the subject.
  • the affinity of the antibody for the BBB-R is modified, i.e., decreased.
  • the effector function of the antibody Fc region is modified.
  • the effector function has been reduced or eliminated relative to the effector function of a wild-type antibody of the same isotype.
  • the effector function is reduced or eliminated by reduction of glycosylation of the antibody.
  • the glycosylation of the antibody is reduced by production of the antibody in an environment that does not permit wild-type glycosylation.
  • the antibody is produced in a non-mammalian cell production system. In another such aspect, the antibody is produced synthetically. In another such aspect, the glycosylation of the antibody is reduced by removal of carbohydrate groups already present on the antibody. In another such aspect, the glycosylation of the antibody is reduced by modification of the antibody such that wild-type glycosylation does not occur. In another such aspect, the Fc region of the antibody comprises a mutation at position 297 such that the wild-type asparagine residue at that position is replaced with another amino acid that interferes with glycosylation at that position. In another aspect, the effector function is reduced or eliminated by modification of the antibody isotype to an isotype that naturally has reduced or eliminated effector function.
  • the Fc region is modified to reduce or eliminate effector function.
  • the effector function is reduced or eliminated by at least one modification of the Fc region.
  • the modification is a point mutation of the Fc region to impair binding to one or more Fc receptors selected from the following positions: 238, 239, 248, 249, 252, 254, 265, 268, 269, 270, 272, 278, 289, 292, 293, 294, 295, 296, 297, 298, 301, 303, 322, 324, 327, 329, 333, 335, 338, 340, 373, 376, 382, 388, 389, 414, 416, 419, 434, 435, 437, 438, and 439.
  • the modification is elimination of some or all of the Fc region.
  • the effector function is reduced or eliminated by deletion of all or a portion of the Fc region, or by engineering the antibody such that it does not include an Fc region competent for effector function.
  • the antibody is selected from a Fab or a single chain antibody.
  • the Fc region and/or the non-Fc region of the antibody is modified to reduce or eliminate activation of the complement pathway by the antibody.
  • the modification is a point mutation of the Fc region to impair binding to C1q selected from the following positions: 270, 322, 329, and 321.
  • the modification is elimination of some or all of the Fc region.
  • complement-triggering function is reduced or eliminated by deletion of all or a portion of the Fc region, or by engineering the antibody such that it does not include an Fc region that engages the complement pathway.
  • the antibody is selected from a Fab or a single chain antibody.
  • the non-Fc region of the antibody is modified to reduce or eliminate activation of the complement pathway by the antibody.
  • the modification is a point mutation of the CH1 region to impair binding to C3.
  • the point mutation is at position 132 (see, e.g., Vidarte et al., (2001) J. Biol. Chem. 276(41): 38217-38223).
  • the dose amount and/or frequency of administration of the antibody is modulated to reduce the concentration of the antibody to which the red blood cells are exposed.
  • the antibody is modified to comprise pH-sensitive binding to the BBB-R.
  • a further compound is administered in addition to the antibody and the coupled compound.
  • the further compound is responsible for or contributes to the lack of reduction of reticulocyte levels.
  • the further compound inhibits or prevents the activation or activity of the complement pathway (see, e.g., Mollnes and Kirschfink (2006) Molec. Immunol. 43:107-121).
  • the further compound protects reticulocytes from antibody-related depletion.
  • the further compound supports the growth, development, or reestablishment of reticulocytes.
  • the further compound is selected from erythropoietin (EPO), an iron supplement, vitamin C, folic acid and vitamin B12.
  • EPO erythropoietin
  • the further compound is red blood cells or reticulocytes from the same subject.
  • the further compound is red blood cells or reticulocytes from another subject.
  • the compound is a neurological disorder drug.
  • the compound is an imaging agent.
  • the compound is labeled.
  • the antibody is labeled.
  • the antibody does not impair the binding of the BBB-R to one or more of its native ligands.
  • the antibody specifically binds to TfR in such a manner that it does not inhibit binding of the TfR to transferrin.
  • the subject is a mammal.
  • the mammal is a human.
  • the mammal has a neurological disorder.
  • the neurological disorder is selected from the group consisting of Alzheimer's disease (AD), stroke, dementia, muscular dystrophy (MD), multiple sclerosis (MS), amyotrophic lateral sclerosis (ALS), cystic fibrosis, Angelman's syndrome, Liddle syndrome, Parkinson's disease, Pick's disease, Paget's disease, cancer, and traumatic brain injury.
  • AD Alzheimer's disease
  • MD muscular dystrophy
  • MS multiple sclerosis
  • ALS amyotrophic lateral sclerosis
  • cystic fibrosis Angelman's syndrome
  • Liddle syndrome Parkinson's disease
  • Parkinson's disease Pick's disease
  • Paget's disease cancer
  • traumatic brain injury traumatic brain injury
  • the decrease in clearance of the compound is measured relative to the clearance of a compound coupled with a typical antibody not having lowered affinity for the BBB-R. In another aspect, the decrease in clearance of the compound is measured relative to the clearance of the compound in the absence of a coupled antibody.
  • the antibody has an IC50 for the BBB-R from about 1 nM to about 100 ⁇ M. In another such aspect, the IC50 is from about 5 nM to about 100 ⁇ M. In another such aspect, the IC50 is from about 50 nM to about 100 ⁇ M. In another such aspect, the IC50 is from about 100 nM to about 100 ⁇ M. In another aspect, the antibody has an affinity for the BBB-R from about 5 nM to about 50 ⁇ M. In another aspect, the antibody has an affinity for the BBB-R from about 30 nM to about 30 ⁇ M. In another such aspect, the antibody, when coupled to a compound, has an affinity for the BBB-R from about 30 nM to about 1 ⁇ M.
  • the antibody when coupled to a compound, has an affinity for the BBB-R from about 50 nM to about 1 ⁇ M.
  • the compound-coupled antibody specifically binds to TfR and has an affinity for TfR between those affinities observed for the anti-TfR A /BACE1 antibody and the anti-TfR E /BACE1 antibody.
  • the compound-coupled antibody specifically binds to TfR and has an affinity for TfR between those affinities observed for the anti-TfR D /BACE1 antibody and the anti-TfR E /BACE1 antibody.
  • the compound-coupled antibody specifically binds to TfR and has an IC50 for TfR between those IC50s observed for the anti-TfR A /BACE1 antibody and the anti-TfR E /BACE1 antibody. In another such aspect, the compound-coupled antibody specifically binds to TfR and has an IC50 for TfR between those IC50s observed for the anti-TfR D /BACE1 antibody and the anti-TfR E /BACE1 antibody. In one aspect, the affinity of the anti-BBB-R or anti-BBB-R/compound for the BBB-R is measured using scatchard analysis.
  • the affinity of the anti-BBB-R or anti-BBB-R/compound for the BBB-R is measured using BIACORE analysis. In another aspect, the affinity of the anti-BBB-R or anti-BBB-R/compound for the BBB-R is measured using a competition ELISA.
  • the dissociation half-life of the antibody from the BBB-R to which it specifically binds is from about 30 seconds to about 30 minutes. In another such aspect, the dissociation half-life is from about 30 seconds to about 20 minutes. In another such aspect, the dissociation half-life is from about 30 seconds to about 10 minutes. In another such aspect, the dissociation half-life is from about 30 seconds to about 5 minutes. In another such aspect, the dissociation half-life is from about 30 seconds to about 3 minutes. In another such aspect, the dissociation half-life is from about 30 seconds to about 2 minutes. In another such aspect, the dissociation half-life is about two minutes. In another such aspect, the dissociation half-life is one minute or less.
  • the compound-coupled antibody specifically binds to TfR and has a dissociation half-life for TfR between those dissociation half-lives observed for the anti-TfR A /BACE1 antibody and the anti-TfR E /BACE1 antibody from their respective binding to TfR.
  • the compound-coupled antibody specifically binds to TfR and has a dissociation half-life for TfR between those dissociation half-lives observed for the anti-TfR D /BACE1 antibody and the anti-TfR E /BACE1 antibody from their respective binding to TfR.
  • the dissociation half-life of the anti-BBB-R or anti-BBB-R/compound for the BBB-R is measured using BIACORE analysis. In another aspect, the dissociation half-life of the anti-BBB-R or anti-BBB-R/compound for the BBB-R is measured using a competition binding assay, such as a competition ELISA.
  • the compound-coupled antibody is administered at a therapeutic dose.
  • the therapeutic dose is a dose that saturates the BBB-R to which the antibody specifically binds.
  • the compound-coupled antibody is administered at a dose and dose frequency that minimizes red blood cell interaction with the compound-coupled antibody while still facilitating compound delivery across the BBB into the CNS at therapeutic levels.
  • the compound is covalently coupled to the antibody.
  • the compound is joined to the antibody by a linker.
  • the linker is cleavable.
  • the linker is not cleavable.
  • the compound is directly linked to the antibody.
  • the antibody is a multispecific antibody and the compound forms one portion of the multispecific antibody.
  • the multispecific antibody comprises a first antigen binding site which binds the BBB-R and a second antigen binding site which binds a brain antigen.
  • the brain antigen is selected from the group consisting of: beta-secretase 1 (BACE1), Abeta, epidermal growth factor receptor (EGFR), human epidermal growth factor receptor 2 (HER2), Tau, apolipoprotein E4 (ApoE4), alpha-synuclein, CD20, huntingtin, prion protein (PrP), leucine rich repeat kinase 2 (LRRK2), parkin, presenilin 1, presenilin 2, gamma secretase, death receptor 6 (DR6), amyloid precursor protein (APP), p75 neurotrophin receptor (p75NTR), interleukin 6 receptor (IL6R), TNF receptor 1 (TNFR1), interleukin 1 beta (IL1 ⁇ ), and caspase 6.
  • BACE1 beta-secretase 1
  • EGFR epidermal growth factor receptor
  • HER2 human epidermal growth factor receptor 2
  • Tau apolipoprotein E4
  • the multispecific antibody binds both TfR and BACE1. In another such aspect, the multispecific antibody binds both TfR and Abeta. In another such aspect, the multispecific antibody is labeled. In another aspect, the compound is reversibly coupled to the antibody such that the compound is released from the antibody concurrent with or after BBB transport.
  • the BBB-R is selected from the group consisting of transferrin receptor (TfR), insulin receptor, insulin-like growth factor receptor (IGF receptor), low density lipoprotein receptor-related protein 8 (LRP8), low density lipoprotein receptor-related protein 1 (LRP1), glucose transporter 1 (Glut1) and heparin-binding epidermal growth factor-like growth factor (HB-EGF).
  • TfR transferrin receptor
  • IGF receptor insulin-like growth factor receptor
  • LRP8 low density lipoprotein receptor-related protein 8
  • LRP1 low density lipoprotein receptor-related protein 1
  • Glut1 glucose transporter 1
  • HB-EGF heparin-binding epidermal growth factor-like growth factor
  • the BBB-R is a human BBB-R. In one such aspect, the BBB-R is TfR. In another such aspect, the BBB-R is TfR, and the antibody does not inhibit TfR activity. In another such aspect, the BBB-R is TfR and the antibody does not inhibit the binding of TfR to transferrin.
  • the red blood cells are immature red blood cells.
  • the immature red blood cells are reticulocytes.
  • reduction of reticulocyte levels is accompanied by acute clinical symptoms.
  • the method further comprises the step of monitoring the subject for depletion of red blood cells.
  • one or more properties of the antibody have been modified to reduce the impact of the antibody on reticulocyte levels and/or reduce the severity or presence of acute clinical symptoms in the subject.
  • the affinity of the antibody for the BBB-R is modified, i.e., decreased.
  • the effector function of the antibody Fc region is modified.
  • the effector function has been reduced or eliminated relative to the effector function of a wild-type antibody of the same isotype.
  • the effector function is reduced or eliminated by reduction of glycosylation of the antibody.
  • the glycosylation of the antibody is reduced by production of the antibody in an environment that does not permit wild-type glycosylation.
  • the antibody is produced in a non-mammalian cell production system. In another such aspect, the antibody is produced synthetically. In another such aspect, the glycosylation of the antibody is reduced by removal of carbohydrate groups already present on the antibody. In another such aspect, the glycosylation of the antibody is reduced by modification of the antibody such that wild-type glycosylation does not occur. In another such aspect, the Fc region of the antibody comprises a mutation at position 297 such that the wild-type asparagine residue at that position is replaced with another amino acid that interferes with glycosylation at that position. In another aspect, the effector function is reduced or eliminated by modification of the antibody isotype to an isotype that naturally has reduced or eliminated effector function.
  • the Fc region is modified to reduce or eliminate effector function.
  • the effector function is reduced or eliminated by at least one modification of the Fc region.
  • the modification is a point mutation of the Fc region to impair binding to one or more Fc receptors selected from the following positions: 238, 239, 248, 249, 252, 254, 265, 268, 269, 270, 272, 278, 289, 292, 293, 294, 295, 296, 297, 298, 301, 303, 322, 324, 327, 329, 333, 335, 338, 340, 373, 376, 382, 388, 389, 414, 416, 419, 434, 435, 437, 438, and 439.
  • the modification is elimination of some or all of the Fc region.
  • the effector function is reduced or eliminated by deletion of all or a portion of the Fc region, or by engineering the antibody such that it does not include an Fc region competent for effector function.
  • the antibody is selected from a Fab or a single chain antibody.
  • the Fc region and/or the non-Fc region of the antibody is modified to reduce or eliminate activation of the complement pathway by the antibody.
  • the modification is a point mutation of the Fc region to impair binding to C1q selected from the following positions: 270, 322, 329, and 321.
  • the modification is elimination of some or all of the Fc region.
  • complement-triggering function is reduced or eliminated by deletion of all or a portion of the Fc region, or by engineering the antibody such that it does not include an Fc region that engages the complement pathway.
  • the antibody is selected from a Fab or a single chain antibody.
  • the non-Fc region of the antibody is modified to reduce or eliminate activation of the complement pathway by the antibody.
  • the modification is a point mutation of the CH1 region to impair binding to C3.
  • the point mutation is at position 132 (see, e.g., Vidarte et al., (2001) J. Biol. Chem. 276(41): 38217-38223).
  • the dose amount and/or frequency of administration of the antibody is modulated to reduce the concentration of the antibody to which the red blood cells are exposed.
  • the antibody is modified to comprise pH-sensitive binding to the BBB-R.
  • a further compound is administered in addition to the antibody and the coupled compound.
  • the further compound is responsible for or contributes to the lack of reduction of reticulocyte levels.
  • the further compound inhibits or prevents the activation or activity of the complement pathway (see, e.g., Mollnes and Kirschfink (2006) Molec. Immunol. 43:107-121).
  • the further compound protects reticulocytes from antibody-related depletion.
  • the further compound supports the growth, development, or reestablishment of reticulocytes.
  • the further compound is selected from erythropoietin (EPO), an iron supplement, vitamin C, folic acid and vitamin B12.
  • EPO erythropoietin
  • the further compound is red blood cells or reticulocytes from the same subject.
  • the further compound is red blood cells or reticulocytes from another subject.
  • the compound is a neurological disorder drug.
  • the compound is an imaging agent.
  • the compound is labeled.
  • the antibody is labeled.
  • the antibody does not impair the binding of the BBB-R to one or more of its native ligands.
  • the antibody specifically binds to TfR in such a manner that it does not inhibit binding of the TfR to transferrin.
  • the compound is administered to a mammal.
  • the mammal is a human.
  • the mammal has a neurological disorder.
  • the neurological disorder is selected from the group consisting of Alzheimer's disease (AD), stroke, dementia, muscular dystrophy (MD), multiple sclerosis (MS), amyotrophic lateral sclerosis (ALS), cystic fibrosis, Angelman's syndrome, Liddle syndrome, Parkinson's disease, Pick's disease, Paget's disease, cancer, and traumatic brain injury.
  • AD Alzheimer's disease
  • MD muscular dystrophy
  • MS multiple sclerosis
  • ALS amyotrophic lateral sclerosis
  • cystic fibrosis Angelman's syndrome
  • Liddle syndrome Parkinson's disease
  • Parkinson's disease Pick's disease
  • Paget's disease cancer
  • traumatic brain injury traumatic brain injury
  • the increase in CNS retention of the compound is measured relative to the CNS retention of a compound coupled with a typical antibody not having lowered affinity for the BBB-R.
  • the increase in CNS retention of the compound is measured as a ratio of the amount of the compound found in the CNS relative to the amount found in the serum at one or more time points after administration. In another such aspect, the increase in CNS retention results in a ratio of greater than 0.1% at one or more time points after administration.
  • the increase in CNS retention of the compound is measured relative to the CNS retention of a compound in the absence of a coupled antibody.
  • the increase in CNS retention of the compound is measured by imaging.
  • the increase in CNS retention of the compound is measured by an indirect readout such as a modification of one or more physiological symptoms.
  • the antibody has an IC50 for the BBB-R from about 1 nM to about 100 ⁇ M. In another such aspect, the IC50 is from about 5 nM to about 100 ⁇ M. In another such aspect, the IC50 is from about 50 nM to about 100 ⁇ M. In another such aspect, the IC50 is from about 100 nM to about 100 ⁇ M. In another aspect, the antibody has an affinity for the BBB-R from about 5 nM to about 50 ⁇ M. In another aspect, the antibody has an affinity for the BBB-R from about 30 nM to about 30 ⁇ M. In another such aspect, the antibody, when coupled to a compound, has an affinity for the BBB-R from about 30 nM to about 1 ⁇ M.
  • the antibody when coupled to a compound, has an affinity for the BBB-R from about 50 nM to about 1 ⁇ M.
  • the compound-coupled antibody specifically binds to TfR and has an affinity for TfR between those affinities observed for the anti-TfR A /BACE1 antibody and the anti-TfR E /BACE1 antibody.
  • the compound-coupled antibody specifically binds to TfR and has an affinity for TfR between those affinities observed for the anti-TfR D /BACE1 antibody and the anti-TfR E /BACE1 antibody.
  • the compound-coupled antibody specifically binds to TfR and has an IC50 for TfR between those IC50s observed for the anti-TfR A /BACE1 antibody and the anti-TfR E /BACE1 antibody. In another such aspect, the compound-coupled antibody specifically binds to TfR and has an IC50 for TfR between those IC50s observed for the anti-TfR D /BACE1 antibody and the anti-TfR E /BACE1 antibody. In one aspect, the affinity of the anti-BBB-R or anti-BBB-R/compound for the BBB-R is measured using scatchard analysis.
  • the affinity of the anti-BBB-R or anti-BBB-R/compound for the BBB-R is measured using BIACORE analysis. In another aspect, the affinity of the anti-BBB-R or anti-BBB-R/compound for the BBB-R is measured using a competition ELISA.
  • the dissociation half-life of the antibody from the BBB-R to which it specifically binds is from about 30 seconds to about 30 minutes. In another such aspect, the dissociation half-life is from about 30 seconds to about 20 minutes. In another such aspect, the dissociation half-life is from about 30 seconds to about 10 minutes. In another such aspect, the dissociation half-life is from about 30 seconds to about 5 minutes. In another such aspect, the dissociation half-life is from about 30 seconds to about 3 minutes. In another such aspect, the dissociation half-life is from about 30 seconds to about 2 minutes. In another such aspect, the dissociation half-life is about two minutes. In another such aspect, the dissociation half-life is one minute or less.
  • the compound-coupled antibody specifically binds to TfR and has a dissociation half-life for TfR between those dissociation half-lives observed for the anti-TfR A /BACE1 antibody and the anti-TfR E /BACE1 antibody from their respective binding to TfR.
  • the compound-coupled antibody specifically binds to TfR and has a dissociation half-life for TfR between those dissociation half-lives observed for the anti-TfR D /BACE1 antibody and the anti-TfR E /BACE1 antibody from their respective binding to TfR.
  • the dissociation half-life of the anti-BBB-R or anti-BBB-R/compound for the BBB-R is measured using BIACORE analysis. In another aspect, the dissociation half-life of the anti-BBB-R or anti-BBB-R/compound for the BBB-R is measured using a competition binding assay, such as a competition ELISA.
  • the compound-coupled antibody is administered at a therapeutic dose.
  • the therapeutic dose is a dose that saturates the BBB-R to which the antibody specifically binds.
  • the compound-coupled antibody is administered at a dose and dose frequency that minimizes red blood cell interaction with the compound-coupled antibody while still facilitating compound delivery across the BBB into the CNS at therapeutic levels.
  • the compound is covalently coupled to the antibody.
  • the compound is joined to the antibody by a linker.
  • the linker is cleavable.
  • the linker is not cleavable.
  • the compound is directly linked to the antibody.
  • the antibody is a multispecific antibody and the compound forms one portion of the multispecific antibody.
  • the multispecific antibody comprises a first antigen binding site which binds the BBB-R and a second antigen binding site which binds a brain antigen.
  • the brain antigen is selected from the group consisting of: beta-secretase 1 (BACE1), Abeta, epidermal growth factor receptor (EGFR), human epidermal growth factor receptor 2 (HER2), Tau, apolipoprotein E4 (ApoE4), alpha-synuclein, CD20, huntingtin, prion protein (PrP), leucine rich repeat kinase 2 (LRRK2), parkin, presenilin 1, presenilin 2, gamma secretase, death receptor 6 (DR6), amyloid precursor protein (APP), p75 neurotrophin receptor (p75NTR), interleukin 6 receptor (IL6R), TNF receptor 1 (TNFR1), interleukin 1 beta (IL1 ⁇ ), and caspase 6.
  • BACE1 beta-secretase 1
  • EGFR epidermal growth factor receptor
  • HER2 human epidermal growth factor receptor 2
  • Tau apolipoprotein E4
  • the multispecific antibody binds both TfR and BACE1. In another such aspect, the multispecific antibody binds both TfR and Abeta. In another such aspect, the multispecific antibody is labeled. In another aspect, the compound is reversibly coupled to the antibody such that the compound is released from the antibody concurrent with or after BBB transport.
  • the invention provides a method of optimizing the pharmcokinetics and/or pharmacodynamics of a compound to be efficacious in the CNS of a subject, wherein the compound is coupled to an antibody which binds with low affinity to a BBB-R, and the antibody is selected such that its affinity for the BBB-R after coupling to the compound results in an amount of transport of the antibody conjugated to the compound across the BBB that optimizes the pharmacokinetics and/or pharmacodynamics of the compound in the CNS, wherein reduction of red blood cell levels in the subject upon compound-coupled antibody administration to the subject is decreased or eliminated.
  • the BBB-R is selected from the group consisting of transferrin receptor (TfR), insulin receptor, insulin-like growth factor receptor (IGF receptor), low density lipoprotein receptor-related protein 8 (LRP8), low density lipoprotein receptor-related protein 1 (LRP1), glucose transporter 1 (Glut1) and heparin-binding epidermal growth factor-like growth factor (HB-EGF).
  • TfR transferrin receptor
  • IGF receptor insulin-like growth factor receptor
  • LRP8 low density lipoprotein receptor-related protein 8
  • LRP1 low density lipoprotein receptor-related protein 1
  • Glut1 glucose transporter 1
  • HB-EGF heparin-binding epidermal growth factor-like growth factor
  • the BBB-R is a human BBB-R.
  • the BBB-R is TfR.
  • the BBB-R is TfR, and the antibody does not inhibit TfR activity.
  • the BBB-R is TfR and the antibody does not inhibit the binding of TfR
  • the red blood cells are immature red blood cells.
  • the immature red blood cells are reticulocytes.
  • reduction of reticulocyte levels is accompanied by acute clinical symptoms.
  • the method further comprises the step of monitoring the subject for depletion of red blood cells.
  • one or more properties of the antibody have been modified to reduce the impact of the antibody on reticulocyte levels and/or reduce the severity or presence of acute clinical symptoms in the subject.
  • the affinity of the antibody for the BBB-R is modified, i.e., decreased.
  • the effector function of the antibody Fc region is modified.
  • the effector function has been reduced or eliminated relative to the effector function of a wild-type antibody of the same isotype.
  • the effector function is reduced or eliminated by reduction of glycosylation of the antibody.
  • the glycosylation of the antibody is reduced by production of the antibody in an environment that does not permit wild-type glycosylation.
  • the antibody is produced in a non-mammalian cell production system. In another such aspect, the antibody is produced synthetically. In another such aspect, the glycosylation of the antibody is reduced by removal of carbohydrate groups already present on the antibody. In another such aspect, the glycosylation of the antibody is reduced by modification of the antibody such that wild-type glycosylation does not occur. In another such aspect, the Fc region of the antibody comprises a mutation at position 297 such that the wild-type asparagine residue at that position is replaced with another amino acid that interferes with glycosylation at that position. In another aspect, the effector function is reduced or eliminated by modification of the antibody isotype to an isotype that naturally has reduced or eliminated effector function.
  • the Fc region is modified to reduce or eliminate effector function.
  • the effector function is reduced or eliminated by at least one modification of the Fc region.
  • the modification is a point mutation of the Fc region to impair binding to one or more Fc receptors selected from the following positions: 238, 239, 248, 249, 252, 254, 265, 268, 269, 270, 272, 278, 289, 292, 293, 294, 295, 296, 297, 298, 301, 303, 322, 324, 327, 329, 333, 335, 338, 340, 373, 376, 382, 388, 389, 414, 416, 419, 434, 435, 437, 438, and 439.
  • the modification is elimination of some or all of the Fc region.
  • the effector function is reduced or eliminated by deletion of all or a portion of the Fc region, or by engineering the antibody such that it does not include an Fc region competent for effector function.
  • the antibody is selected from a Fab or a single chain antibody.
  • the Fc region and/or the non-Fc region of the antibody is modified to reduce or eliminate activation of the complement pathway by the antibody.
  • the modification is a point mutation of the Fc region to impair binding to C1q selected from the following positions: 270, 322, 329, and 321.
  • the modification is elimination of some or all of the Fc region.
  • complement-triggering function is reduced or eliminated by deletion of all or a portion of the Fc region, or by engineering the antibody such that it does not include an Fc region that engages the complement pathway.
  • the antibody is selected from a Fab or a single chain antibody.
  • the non-Fc region of the antibody is modified to reduce or eliminate activation of the complement pathway by the antibody.
  • the modification is a point mutation of the CH1 region to impair binding to C3.
  • the point mutation is at position 132 (see, e.g., Vidarte et al., (2001) J. Biol. Chem. 276(41): 38217-38223).
  • the dose amount and/or frequency of administration of the antibody is modulated to reduce the concentration of the antibody to which the red blood cells are exposed.
  • the antibody is modified to comprise pH-sensitive binding to the BBB-R.
  • a further compound is administered in addition to the antibody and the coupled compound.
  • the further compound is responsible for or contributes to the lack of reduction of reticulocyte levels.
  • the further compound inhibits or prevents the activation or activity of the complement pathway (see, e.g., Mollnes and Kirschfink (2006) Molec. Immunol. 43:107-121).
  • the further compound protects reticulocytes from antibody-related depletion.
  • the further compound supports the growth, development, or reestablishment of reticulocytes.
  • the further compound is selected from erythropoietin (EPO), an iron supplement, vitamin C, folic acid and vitamin B12.
  • EPO erythropoietin
  • the further compound is red blood cells or reticulocytes from the same subject.
  • the further compound is red blood cells or reticulocytes from another subject.
  • the compound is a neurological disorder drug.
  • the compound is an imaging agent.
  • the compound is labeled.
  • the antibody is labeled.
  • the antibody does not impair the binding of the BBB-R to one or more of its native ligands.
  • the antibody specifically binds to TfR in such a manner that it does not inhibit binding of the TfR to transferrin.
  • the BBB is in a mammal.
  • the mammal is a human.
  • the mammal has a neurological disorder.
  • the neurological disorder is selected from the group consisting of Alzheimer's disease (AD), stroke, dementia, muscular dystrophy (MD), multiple sclerosis (MS), amyotrophic lateral sclerosis (ALS), cystic fibrosis, Angelman's syndrome, Liddle syndrome, Parkinson's disease, Pick's disease, Paget's disease, cancer, and traumatic brain injury.
  • the BBB is in a human.
  • the optimizing may include the generation of a series of antibody-compound complexes in which each antibody has a different affinity for the BBB-R, and assessing the pharmacokinetics and/or pharmacodynamics of each in the CNS.
  • optimizing may be relative to a known standard, such as, but not limited to, the pharmacokinetics and/or pharmacodynamics of the compound when directly introduced into the CNS or when introduced to the subject in the absence of a coupled anti-BBB-R antibody.
  • the antibody has an IC50 for the BBB-R from about 1 nM to about 100 ⁇ M. In another such aspect, the IC50 is from about 5 nM to about 100 ⁇ M. In another such aspect, the IC50 is from about 50 nM to about 100 ⁇ M. In another such aspect, the IC50 is from about 100 nM to about 100 ⁇ M. In another aspect, the antibody has an affinity for the BBB-R from about 5 nM to about 50 ⁇ M. In another aspect, the antibody has an affinity for the BBB-R from about 30 nM to about 30 ⁇ M. In another such aspect, the antibody, when coupled to a compound, has an affinity for the BBB-R from about 30 nM to about 1 ⁇ M.
  • the antibody when coupled to a compound, has an affinity for the BBB-R from about 50 nM to about 1 ⁇ M.
  • the compound-coupled antibody specifically binds to TfR and has an affinity for TfR between those affinities observed for the anti-TfR A /BACE1 antibody and the anti-TfR E /BACE1 antibody.
  • the compound-coupled antibody specifically binds to TfR and has an affinity for TfR between those affinities observed for the anti-TfR D /BACE1 antibody and the anti-TfR E /BACE1 antibody.
  • the compound-coupled antibody specifically binds to TfR and has an IC50 for TfR between those IC50s observed for the anti-TfR A /BACE1 antibody and the anti-TfR E /BACE1 antibody. In another such aspect, the compound-coupled antibody specifically binds to TfR and has an IC50 for TfR between those IC50s observed for the anti-TfR D /BACE1 antibody and the anti-TfR E /BACE1 antibody. In one aspect, the affinity of the anti-BBB-R or anti-BBB-R/compound for the BBB-R is measured using scatchard analysis.
  • the affinity of the anti-BBB-R or anti-BBB-R/compound for the BBB-R is measured using BIACORE analysis. In another aspect, the affinity of the anti-BBB-R or anti-BBB-R/compound for the BBB-R is measured using a competition ELISA.
  • the dissociation half-life of the antibody from the BBB-R to which it specifically binds is from about 30 seconds to about 30 minutes. In another such aspect, the dissociation half-life is from about 30 seconds to about 20 minutes. In another such aspect, the dissociation half-life is from about 30 seconds to about 10 minutes. In another such aspect, the dissociation half-life is from about 30 seconds to about 5 minutes. In another such aspect, the dissociation half-life is from about 30 seconds to about 3 minutes. In another such aspect, the dissociation half-life is from about 30 seconds to about 2 minutes. In another such aspect, the dissociation half-life is about two minutes. In another such aspect, the dissociation half-life is one minute or less.
  • the compound-coupled antibody specifically binds to TfR and has a dissociation half-life for TfR between those dissociation half-lives observed for the anti-TfR A /BACE1 antibody and the anti-TfR E /BACE1 antibody from their respective binding to TfR.
  • the compound-coupled antibody specifically binds to TfR and has a dissociation half-life for TfR between those dissociation half-lives observed for the anti-TfR D /BACE1 antibody and the anti-TfR E /BACE1 antibody from their respective binding to TfR.
  • the dissociation half-life of the anti-BBB-R or anti-BBB-R/compound for the BBB-R is measured using BIACORE analysis. In another aspect, the dissociation half-life of the anti-BBB-R or anti-BBB-R/compound for the BBB-R is measured using a competition binding assay, such as a competition ELISA.
  • the compound-coupled antibody is administered at a therapeutic dose.
  • the therapeutic dose is a dose that saturates the BBB-R to which the antibody specifically binds.
  • the compound-coupled antibody is administered at a dose and dose frequency that minimizes red blood cell interaction with the compound-coupled antibody while still facilitating compound delivery across the BBB into the CNS at therapeutic levels.
  • the compound is covalently coupled to the antibody.
  • the compound is joined to the antibody by a linker.
  • the linker is cleavable.
  • the linker is not cleavable.
  • the compound is directly linked to the antibody.
  • the antibody is a multispecific antibody and the compound forms one portion of the multispecific antibody.
  • the multispecific antibody comprises a first antigen binding site which binds the BBB-R and a second antigen binding site which binds a brain antigen.
  • the brain antigen is selected from the group consisting of: beta-secretase 1 (BACE1), Abeta, epidermal growth factor receptor (EGFR), human epidermal growth factor receptor 2 (HER2), Tau, apolipoprotein E4 (ApoE4), alpha-synuclein, CD20, huntingtin, prion protein (PrP), leucine rich repeat kinase 2 (LRRK2), parkin, presenilin 1, presenilin 2, gamma secretase, death receptor 6 (DR6), amyloid precursor protein (APP), p75 neurotrophin receptor (p75NTR), interleukin 6 receptor (IL6R), TNF receptor 1 (TNFR1), interleukin 1 beta (IL1 ⁇ ), and caspase 6.
  • BACE1 beta-secretase 1
  • EGFR epidermal growth factor receptor
  • HER2 human epidermal growth factor receptor 2
  • Tau apolipoprotein E4
  • the multispecific antibody binds both TfR and BACE1. In another such aspect, the multispecific antibody binds both TfR and Abeta. In another such aspect, the multispecific antibody is labeled. In another aspect, the compound is reversibly coupled to the antibody such that the compound is released from the antibody concurrent with or after BBB transport.
  • the invention provides a method of treating a neurological disorder in a mammal comprising treating the mammal with an antibody that binds a BBB-R and is coupled to a compound, wherein the antibody has been selected to have a low affinity for the BBB-R and thereby improves CNS uptake of the antibody and coupled compound, and wherein reduction of red blood cell levels in the subject upon compound-coupled antibody administration to the subject is decreased or eliminated.
  • the BBB-R is selected from the group consisting of transferrin receptor (TfR), insulin receptor, insulin-like growth factor receptor (IGF receptor), low density lipoprotein receptor-related protein 8 (LRP8), low density lipoprotein receptor-related protein 1 (LRP1), glucose transporter 1 (Glut1) and heparin-binding epidermal growth factor-like growth factor (HB-EGF).
  • TfR transferrin receptor
  • IGF receptor insulin-like growth factor receptor
  • LRP8 low density lipoprotein receptor-related protein 8
  • LRP1 low density lipoprotein receptor-related protein 1
  • Glut1 glucose transporter 1
  • HB-EGF heparin-binding epidermal growth factor-like growth factor
  • the BBB-R is a human BBB-R.
  • the BBB-R is TfR.
  • the BBB-R is TfR, and the antibody does not inhibit TfR activity.
  • the BBB-R is TfR and the antibody does not inhibit the binding of TfR
  • the red blood cells are immature red blood cells.
  • the immature red blood cells are reticulocytes.
  • reduction of reticulocyte levels is accompanied by acute clinical symptoms.
  • the method further comprises the step of monitoring the subject for depletion of red blood cells.
  • one or more properties of the antibody have been modified to reduce the impact of the antibody on reticulocyte levels and/or reduce the severity or presence of acute clinical symptoms in the subject.
  • the affinity of the antibody for the BBB-R is modified, i.e., decreased.
  • the effector function of the antibody Fc region is modified.
  • the effector function has been reduced or eliminated relative to the effector function of a wild-type antibody of the same isotype.
  • the effector function is reduced or eliminated by reduction of glycosylation of the antibody.
  • the glycosylation of the antibody is reduced by production of the antibody in an environment that does not permit wild-type glycosylation.
  • the antibody is produced in a non-mammalian cell production system. In another such aspect, the antibody is produced synthetically. In another such aspect, the glycosylation of the antibody is reduced by removal of carbohydrate groups already present on the antibody. In another such aspect, the glycosylation of the antibody is reduced by modification of the antibody such that wild-type glycosylation does not occur. In another such aspect, the Fc region of the antibody comprises a mutation at position 297 such that the wild-type asparagine residue at that position is replaced with another amino acid that interferes with glycosylation at that position. In another aspect, the effector function is reduced or eliminated by modification of the antibody isotype to an isotype that naturally has reduced or eliminated effector function.
  • the Fc region is modified to reduce or eliminate effector function.
  • the effector function is reduced or eliminated by at least one modification of the Fc region.
  • the modification is a point mutation of the Fc region to impair binding to one or more Fc receptors selected from the following positions: 238, 239, 248, 249, 252, 254, 265, 268, 269, 270, 272, 278, 289, 292, 293, 294, 295, 296, 297, 298, 301, 303, 322, 324, 327, 329, 333, 335, 338, 340, 373, 376, 382, 388, 389, 414, 416, 419, 434, 435, 437, 438, and 439.
  • the modification is elimination of some or all of the Fc region.
  • the effector function is reduced or eliminated by deletion of all or a portion of the Fc region, or by engineering the antibody such that it does not include an Fc region competent for effector function.
  • the antibody is selected from a Fab or a single chain antibody.
  • the dose amount and/or frequency of administration of the antibody is modulated to reduce the concentration of the antibody to which the red blood cells are exposed.
  • the antibody is modified to comprise pH-sensitive binding to the BBB-R.
  • a further compound is administered in addition to the antibody and the coupled compound.
  • the further compound is responsible for or contributes to the lack of reduction of reticulocyte levels.
  • the further compound inhibits or prevents the activation or activity of the complement pathway (see, e.g., Mollnes and Kirschfink (2006) Molec. Immunol. 43:107-121).
  • the further compound protects reticulocytes from antibody-related depletion.
  • the further compound supports the growth, development, or reestablishment of reticulocytes.
  • the further compound is selected from erythropoietin (EPO), an iron supplement, vitamin C, folic acid and vitamin B12.
  • EPO erythropoietin
  • the further compound is red blood cells or reticulocytes from the same subject.
  • the further compound is red blood cells or reticulocytes from another subject.
  • the compound is a neurological disorder drug.
  • the compound is an imaging agent.
  • the compound is labeled.
  • the antibody is labeled.
  • the antibody does not impair the binding of the BBB-R to one or more of its native ligands.
  • the antibody specifically binds to TfR in such a manner that it does not inhibit binding of the TfR to transferrin.
  • the mammal is a human. In another such aspect, the mammal has a neurological disorder.
  • the neurological disorder is selected from the group consisting of Alzheimer's disease (AD), stroke, dementia, muscular dystrophy (MD), multiple sclerosis (MS), amyotrophic lateral sclerosis (ALS), cystic fibrosis, Angelman's syndrome, Liddle syndrome, Parkinson's disease, Pick's disease, Paget's disease, cancer, and traumatic brain injury.
  • AD Alzheimer's disease
  • MD muscular dystrophy
  • MS multiple sclerosis
  • ALS amyotrophic lateral sclerosis
  • cystic fibrosis Angelman's syndrome
  • Liddle syndrome Parkinson's disease
  • Parkinson's disease Pick's disease
  • Paget's disease cancer
  • traumatic brain injury traumatic brain injury
  • the treating results in lessening or elimination of disorder symptoms. In another aspect, the treating results in amelioration of the neurological disorder.
  • the antibody has an IC50 for the BBB-R from about 1 nM to about 100 ⁇ M. In another such aspect, the IC50 is from about 5 nM to about 100 ⁇ M. In another such aspect, the IC50 is from about 50 nM to about 100 ⁇ M. In another such aspect, the IC50 is from about 100 nM to about 100 ⁇ M. In another aspect, the antibody has an affinity for the BBB-R from about 5 nM to about 50 ⁇ M. In another aspect, the antibody has an affinity for the BBB-R from about 30 nM to about 30 ⁇ M. In another such aspect, the antibody, when coupled to a compound, has an affinity for the BBB-R from about 30 nM to about 1 ⁇ M.
  • the antibody when coupled to a compound, has an affinity for the BBB-R from about 50 nM to about 1 ⁇ M.
  • the compound-coupled antibody specifically binds to TfR and has an affinity for TfR between those affinities observed for the anti-TfR A /BACE1 antibody and the anti-TfR E /BACE1 antibody.
  • the compound-coupled antibody specifically binds to TfR and has an affinity for TfR between those affinities observed for the anti-TfR D /BACE1 antibody and the anti-TfR E /BACE1 antibody.
  • the compound-coupled antibody specifically binds to TfR and has an IC50 for TfR between those IC50s observed for the anti-TfR A /BACE1 antibody and the anti-TfR E /BACE1 antibody. In another such aspect, the compound-coupled antibody specifically binds to TfR and has an IC50 for TfR between those IC50s observed for the anti-TfR D /BACE1 antibody and the anti-TfR E /BACE1 antibody. In one aspect, the affinity of the anti-BBB-R or anti-BBB-R/compound for the BBB-R is measured using scatchard analysis.
  • the affinity of the anti-BBB-R or anti-BBB-R/compound for the BBB-R is measured using BIACORE analysis. In another aspect, the affinity of the anti-BBB-R or anti-BBB-R/compound for the BBB-R is measured using a competition ELISA.
  • the dissociation half-life of the antibody from the BBB-R to which it specifically binds is from about 30 seconds to about 30 minutes. In another such aspect, the dissociation half-life is from about 30 seconds to about 20 minutes. In another such aspect, the dissociation half-life is from about 30 seconds to about 10 minutes. In another such aspect, the dissociation half-life is from about 30 seconds to about 5 minutes. In another such aspect, the dissociation half-life is from about 30 seconds to about 3 minutes. In another such aspect, the dissociation half-life is from about 30 seconds to about 2 minutes. In another such aspect, the dissociation half-life is about two minutes. In another such aspect, the dissociation half-life is one minute or less.
  • the compound-coupled antibody specifically binds to TfR and has a dissociation half-life for TfR between those dissociation half-lives observed for the anti-TfR A /BACE1 antibody and the anti-TfR E /BACE1 antibody from their respective binding to TfR.
  • the compound-coupled antibody specifically binds to TfR and has a dissociation half-life for TfR between those dissociation half-lives observed for the anti-TfR D /BACE1 antibody and the anti-TfR E /BACE1 antibody from their respective binding to TfR.
  • the dissociation half-life of the anti-BBB-R or anti-BBB-R/compound for the BBB-R is measured using BIACORE analysis. In another aspect, the dissociation half-life of the anti-BBB-R or anti-BBB-R/compound for the BBB-R is measured using a competition binding assay, such as a competition ELISA.
  • the compound-coupled antibody is administered at a therapeutic dose.
  • the therapeutic dose is a dose that saturates the BBB-R to which the antibody specifically binds.
  • the compound-coupled antibody is administered at a dose and dose frequency that minimizes red blood cell interaction with the compound-coupled antibody while still facilitating compound delivery across the BBB into the CNS at therapeutic levels.
  • the compound is covalently coupled to the antibody.
  • the compound is joined to the antibody by a linker.
  • the linker is cleavable.
  • the linker is not cleavable.
  • the compound is directly linked to the antibody.
  • the antibody is a multispecific antibody and the compound forms one portion of the multispecific antibody.
  • the multispecific antibody comprises a first antigen binding site which binds the BBB-R and a second antigen binding site which binds a brain antigen.
  • the brain antigen is selected from the group consisting of: beta-secretase 1 (BACE1), Abeta, epidermal growth factor receptor (EGFR), human epidermal growth factor receptor 2 (HER2), Tau, apolipoprotein E4 (ApoE4), alpha-synuclein, CD20, huntingtin, prion protein (PrP), leucine rich repeat kinase 2 (LRRK2), parkin, presenilin 1, presenilin 2, gamma secretase, death receptor 6 (DR6), amyloid precursor protein (APP), p75 neurotrophin receptor (p75NTR), interleukin 6 receptor (IL6R), TNF receptor 1 (TNFR1), interleukin 1 beta (IL1 ⁇ ), and caspase 6.
  • BACE1 beta-secretase 1
  • EGFR epidermal growth factor receptor
  • HER2 human epidermal growth factor receptor 2
  • Tau apolipoprotein E4
  • the multispecific antibody binds both TfR and BACE1. In another such aspect, the multispecific antibody binds both TfR and Abeta. In another such aspect, the multispecific antibody is labeled. In another aspect, the compound is reversibly coupled to the antibody such that the compound is released from the antibody concurrent with or after BBB transport.
  • the invention provides a method of improving the safety in a subject of an antibody that binds a BBB-R comprising modifying one or more properties of the antibody such that administration of the antibody decreases or eliminates reduction of red blood cell levels in the subject observed upon administration of the unmodified antibody.
  • the BBB-R is selected from the group consisting of transferrin receptor (TfR), insulin receptor, insulin-like growth factor receptor (IGF receptor), low density lipoprotein receptor-related protein 8 (LRP8), low density lipoprotein receptor-related protein 1 (LRP1), glucose transporter 1 (Glut1) and heparin-binding epidermal growth factor-like growth factor (HB-EGF).
  • TfR transferrin receptor
  • IGF receptor insulin-like growth factor receptor
  • LRP8 low density lipoprotein receptor-related protein 8
  • LRP1 low density lipoprotein receptor-related protein 1
  • Glut1 glucose transporter 1
  • HB-EGF heparin-binding epidermal growth factor-like growth factor
  • the BBB-R is TfR. In another such aspect, the BBB-R is TfR, and the antibody does not inhibit TfR activity. In another such aspect, the BBB-R is TfR and the antibody does not inhibit the binding of TfR to transferrin.
  • the red blood cells are immature red blood cells.
  • the immature red blood cells are reticulocytes.
  • reduction of reticulocyte levels is accompanied by acute clinical symptoms.
  • one or more properties of the antibody have been modified to reduce the impact of the antibody on reticulocyte levels and/or reduce the severity or presence of acute clinical symptoms in the subject.
  • the affinity of the antibody for the BBB-R is modified, i.e., decreased.
  • the modification of the affinity of the antibody is measured relative to a wild-type antibody of the same isotype not having modified (i.e., decreased) affinity for the BBB-R.
  • the effector function of the antibody Fc region is modified.
  • the effector function has been reduced or eliminated relative to the effector function of a wild-type antibody of the same isotype.
  • the effector function is reduced or eliminated by reduction of glycosylation of the antibody.
  • the glycosylation of the antibody is reduced by production of the antibody in an environment that does not permit wild-type glycosylation.
  • the antibody is produced in a non-mammalian cell production system.
  • the antibody is produced synthetically.
  • the glycosylation of the antibody is reduced by removal of carbohydrate groups already present on the antibody.
  • the glycosylation of the antibody is reduced by modification of the antibody such that wild-type glycosylation does not occur.
  • the Fc region of the antibody comprises a mutation at position 297 such that the wild-type asparagine residue at that position is replaced with another amino acid that interferes with glycosylation at that position.
  • the effector function is reduced or eliminated by modification of the antibody isotype to an isotype that naturally has reduced or eliminated effector function.
  • the Fc region is modified to reduce or eliminate effector function.
  • the effector function is reduced or eliminated by at least one modification of the Fc region.
  • the modification is a point mutation of the Fc region to impair binding to one or more Fc receptors selected from the following positions: 238, 239, 248, 249, 252, 254, 265, 268, 269, 270, 272, 278, 289, 292, 293, 294, 295, 296, 297, 298, 301, 303, 322, 324, 327, 329, 333, 335, 338, 340, 373, 376, 382, 388, 389, 414, 416, 419, 434, 435, 437, 438, and 439.
  • the modification is elimination of some or all of the Fc region.
  • the effector function is reduced or eliminated by deletion of all or a portion of the Fc region, or by engineering the antibody such that it does not include an Fc region competent for effector function.
  • the antibody is selected from a Fab or a single chain antibody.
  • the Fc region and/or the non-Fc region of the antibody is modified to reduce or eliminate activation of the complement pathway by the antibody.
  • the modification is a point mutation of the Fc region to impair binding to C1q selected from the following positions: 270, 322, 329, and 321.
  • the modification is elimination of some or all of the Fc region.
  • complement-triggering function is reduced or eliminated by deletion of all or a portion of the Fc region, or by engineering the antibody such that it does not include an Fc region that engages the complement pathway.
  • the antibody is selected from a Fab or a single chain antibody.
  • the non-Fc region of the antibody is modified to reduce or eliminate activation of the complement pathway by the antibody.
  • the modification is a point mutation of the CH1 region to impair binding to C3.
  • the point mutation is at position 132 (see, e.g., Vidarte et al., (2001) J. Biol. Chem. 276(41): 38217-38223).
  • the dose amount and/or frequency of administration of the antibody is modulated to reduce the concentration of the antibody to which the red blood cells are exposed.
  • the antibody is modified to comprise pH-sensitive binding to the BBB-R.
  • the antibody is coupled with a therapeutic compound.
  • the compound is a neurological disorder drug.
  • the compound is an imaging agent.
  • the compound is labeled.
  • the antibody is labeled.
  • the antibody does not impair the binding of the BBB-R to one or more of its native ligands.
  • the antibody specifically binds to TfR in such a manner that it does not inhibit binding of the TfR to transferrin.
  • the BBB is in a mammal.
  • the mammal is a human.
  • the mammal has a neurological disorder.
  • the neurological disorder is selected from the group consisting of Alzheimer's disease (AD), stroke, dementia, muscular dystrophy (MD), multiple sclerosis (MS), amyotrophic lateral sclerosis (ALS), cystic fibrosis, Angelman's syndrome, Liddle syndrome, Parkinson's disease, Pick's disease, Paget's disease, cancer, and traumatic brain injury.
  • the BBB is in a human.
  • the antibody has an IC50 for the BBB-R from about 1 nM to about 100 ⁇ M. In another such aspect, the IC50 is from about 5 nM to about 100 ⁇ M. In another such aspect, the IC50 is from about 50 nM to about 100 ⁇ M. In another such aspect, the IC50 is from about 100 nM to about 100 ⁇ M. In another aspect, the antibody has an affinity for the BBB-R from about 5 nM to about 50 ⁇ M. In another aspect, the antibody has an affinity for the BBB-R from about 30 nM to about 30 ⁇ M. In another such aspect, the antibody, when coupled to a compound, has an affinity for the BBB-R from about 30 nM to about 1 ⁇ M.
  • the antibody when coupled to a compound, has an affinity for the BBB-R from about 50 nM to about 1 ⁇ M.
  • the compound-coupled antibody specifically binds to TfR and has an affinity for TfR between those affinities observed for the anti-TfR A /BACE1 antibody and the anti-TfR E /BACE1 antibody.
  • the compound-coupled antibody specifically binds to TfR and has an affinity for TfR between those affinities observed for the anti-TfR D /BACE1 antibody and the anti-TfR E /BACE1 antibody.
  • the compound-coupled antibody specifically binds to TfR and has an IC50 for TfR between those IC50s observed for the anti-TfR A /BACE1 antibody and the anti-TfR E /BACE1 antibody. In another such aspect, the compound-coupled antibody specifically binds to TfR and has an IC50 for TfR between those IC50s observed for the anti-TfR D /BACE1 antibody and the anti-TfR E /BACE1 antibody. In one aspect, the affinity of the anti-BBB-R or anti-BBB-R/compound for the BBB-R is measured using scatchard analysis.
  • the affinity of the anti-BBB-R or anti-BBB-R/compound for the BBB-R is measured using BIACORE analysis. In another aspect, the affinity of the anti-BBB-R or anti-BBB-R/compound for the BBB-R is measured using a competition ELISA.
  • the dissociation half-life of the antibody from the BBB-R to which it specifically binds is from about 30 seconds to about 30 minutes. In another such aspect, the dissociation half-life is from about 30 seconds to about 20 minutes. In another such aspect, the dissociation half-life is from about 30 seconds to about 10 minutes. In another such aspect, the dissociation half-life is from about 30 seconds to about 5 minutes. In another such aspect, the dissociation half-life is from about 30 seconds to about 3 minutes. In another such aspect, the dissociation half-life is from about 30 seconds to about 2 minutes. In another such aspect, the dissociation half-life is about two minutes. In another such aspect, the dissociation half-life is one minute or less.
  • the compound-coupled antibody specifically binds to TfR and has a dissociation half-life for TfR between those dissociation half-lives observed for the anti-TfR A /BACE1 antibody and the anti-TfR E /BACE1 antibody from their respective binding to TfR.
  • the compound-coupled antibody specifically binds to TfR and has a dissociation half-life for TfR between those dissociation half-lives observed for the anti-TfR D /BACE1 antibody and the anti-TfR E /BACE1 antibody from their respective binding to TfR.
  • the dissociation half-life of the anti-BBB-R or anti-BBB-R/compound for the BBB-R is measured using BIACORE analysis. In another aspect, the dissociation half-life of the anti-BBB-R or anti-BBB-R/compound for the BBB-R is measured using a competition binding assay, such as a competition ELISA.
  • the antibody is selected from a panel of antibodies based upon the affinity of the selected antibody.
  • the antibody is engineered to have the desired affinity.
  • the antibody is generated using any art-known protein engineering methodology including, but not limited to, phage display, yeast display, random mutagenesis, and site-directed mutagenesis.
  • the compound-coupled antibody is administered at a therapeutic dose.
  • the therapeutic dose is a dose that saturates the BBB-R to which the antibody specifically binds.
  • the compound-coupled antibody is administered at a dose and dose frequency that minimizes red blood cell interaction with the compound-coupled antibody while still facilitating compound delivery across the BBB into the CNS at therapeutic levels.
  • the compound is covalently coupled to the antibody.
  • the compound is joined to the antibody by a linker.
  • the linker is cleavable.
  • the linker is not cleavable.
  • the compound is directly linked to the antibody.
  • the antibody is a multispecific antibody and the compound forms one portion of the multispecific antibody.
  • the multispecific antibody comprises a first antigen binding site which binds the BBB-R and a second antigen binding site which binds a brain antigen.
  • the brain antigen is selected from the group consisting of: beta-secretase 1 (BACE1), Abeta, epidermal growth factor receptor (EGFR), human epidermal growth factor receptor 2 (HER2), Tau, apolipoprotein E4 (ApoE4), alpha-synuclein, CD20, huntingtin, prion protein (PrP), leucine rich repeat kinase 2 (LRRK2), parkin, presenilin 1, presenilin 2, gamma secretase, death receptor 6 (DR6), amyloid precursor protein (APP), p75 neurotrophin receptor (p75NTR), interleukin 6 receptor (IL6R), TNF receptor 1 (TNFR1), interleukin 1 beta (IL1 ⁇ ), and caspase 6.
  • BACE1 beta-secretase 1
  • EGFR epidermal growth factor receptor
  • HER2 human epidermal growth factor receptor 2
  • Tau apolipoprotein E4
  • the multispecific antibody binds both TfR and BACE1. In another such aspect, the multispecific antibody binds both TfR and Abeta. In another such aspect, the multispecific antibody is labeled. In another aspect, the compound is reversibly coupled to the antibody such that the compound is released from the antibody concurrent with or after BBB transport.
  • the invention provides a method of making an antibody useful for transporting a compound across the BBB with improved safety comprising selecting an antibody specific for a blood-brain barrier receptor (BBB-R) that has a desirably low affinity for the BBB-R, and modifying one or more properties of the antibody such that administration of the antibody decreases or eliminates reduction of red blood cell levels in the subject observed upon administration of an unmodified antibody.
  • BBB-R blood-brain barrier receptor
  • the BBB-R is selected from the group consisting of transferrin receptor (TfR), insulin receptor, insulin-like growth factor receptor (IGF receptor), low density lipoprotein receptor-related protein 8 (LRP8), low density lipoprotein receptor-related protein 1 (LRP1), glucose transporter 1 (Glut1) and heparin-binding epidermal growth factor-like growth factor (HB-EGF).
  • TfR transferrin receptor
  • IGF receptor insulin-like growth factor receptor
  • LRP8 low density lipoprotein receptor-related protein 8
  • LRP1 low density lipoprotein receptor-related protein 1
  • Glut1 glucose transporter 1
  • HB-EGF heparin-binding epidermal growth factor-like growth factor
  • the BBB-R is a human BBB-R.
  • the BBB-R is TfR.
  • the BBB-R is TfR, and the antibody does not inhibit TfR activity.
  • the BBB-R is TfR and the antibody does not inhibit the binding of TfR
  • the red blood cells are immature red blood cells.
  • the immature red blood cells are reticulocytes.
  • reduction of reticulocyte levels is accompanied by acute clinical symptoms.
  • one or more properties of the antibody have been modified to reduce the impact of the antibody on reticulocyte levels and/or reduce the severity or presence of acute clinical symptoms in the subject.
  • the affinity of the antibody for the BBB-R is modified, i.e., decreased.
  • the modification of the affinity of the antibody is measured relative to a wild-type antibody of the same isotype not having modified (i.e., decreased) affinity for the BBB-R.
  • the effector function of the antibody Fc region is modified.
  • the effector function has been reduced or eliminated relative to the effector function of a wild-type antibody of the same isotype.
  • the effector function is reduced or eliminated by reduction of glycosylation of the antibody.
  • the glycosylation of the antibody is reduced by production of the antibody in an environment that does not permit wild-type glycosylation.
  • the antibody is produced in a non-mammalian cell production system.
  • the antibody is produced synthetically.
  • the glycosylation of the antibody is reduced by removal of carbohydrate groups already present on the antibody.
  • the glycosylation of the antibody is reduced by modification of the antibody such that wild-type glycosylation does not occur.
  • the Fc region of the antibody comprises a mutation at position 297 such that the wild-type asparagine residue at that position is replaced with another amino acid that interferes with glycosylation at that position.
  • the effector function is reduced or eliminated by modification of the antibody isotype to an isotype that naturally has reduced or eliminated effector function.
  • the Fc region is modified to reduce or eliminate effector function.
  • the effector function is reduced or eliminated by at least one modification of the Fc region.
  • the modification is a point mutation of the Fc region to impair binding to one or more Fc receptors selected from the following positions: 238, 239, 248, 249, 252, 254, 265, 268, 269, 270, 272, 278, 289, 292, 293, 294, 295, 296, 297, 298, 301, 303, 322, 324, 327, 329, 333, 335, 338, 340, 373, 376, 382, 388, 389, 414, 416, 419, 434, 435, 437, 438, and 439.
  • the modification is elimination of some or all of the Fc region.
  • the effector function is reduced or eliminated by deletion of all or a portion of the Fc region, or by engineering the antibody such that it does not include an Fc region competent for effector function.
  • the antibody is selected from a Fab or a single chain antibody.
  • the Fc region and/or the non-Fc region of the antibody is modified to reduce or eliminate activation of the complement pathway by the antibody.
  • the modification is a point mutation of the Fc region to impair binding to C1q selected from the following positions: 270, 322, 329, and 321.
  • the modification is elimination of some or all of the Fc region.
  • complement-triggering function is reduced or eliminated by deletion of all or a portion of the Fc region, or by engineering the antibody such that it does not include an Fc region that engages the complement pathway.
  • the antibody is selected from a Fab or a single chain antibody.
  • the non-Fc region of the antibody is modified to reduce or eliminate activation of the complement pathway by the antibody.
  • the modification is a point mutation of the CH1 region to impair binding to C3.
  • the point mutation is at position 132 (see, e.g., Vidarte et al., (2001) J. Biol. Chem. 276(41): 38217-38223).
  • the dose amount and/or frequency of administration of the antibody is modulated to reduce the concentration of the antibody to which the red blood cells are exposed.
  • the antibody is modified to comprise pH-sensitive binding to the BBB-R.
  • the antibody is coupled with a therapeutic compound.
  • the compound is a neurological disorder drug.
  • the compound is an imaging agent.
  • the compound is labeled.
  • the antibody is labeled.
  • the antibody does not impair the binding of the BBB-R to one or more of its native ligands.
  • the antibody specifically binds to TfR in such a manner that it does not inhibit binding of the TfR to transferrin.
  • the BBB is in a mammal.
  • the mammal is a human.
  • the mammal has a neurological disorder.
  • the neurological disorder is selected from the group consisting of Alzheimer's disease (AD), stroke, dementia, muscular dystrophy (MD), multiple sclerosis (MS), amyotrophic lateral sclerosis (ALS), cystic fibrosis, Angelman's syndrome, Liddle syndrome, Parkinson's disease, Pick's disease, Paget's disease, cancer, and traumatic brain injury.
  • the BBB is in a human.
  • the antibody has an IC50 for the BBB-R from about 1 nM to about 100 ⁇ M. In another such aspect, the IC50 is from about 5 nM to about 100 ⁇ M. In another such aspect, the IC50 is from about 50 nM to about 100 ⁇ M. In another such aspect, the IC50 is from about 100 nM to about 100 ⁇ M. In another aspect, the antibody has an affinity for the BBB-R from about 5 nM to about 50 ⁇ M. In another aspect, the antibody has an affinity for the BBB-R from about 30 nM to about 30 ⁇ M. In another such aspect, the antibody, when coupled to a compound, has an affinity for the BBB-R from about 30 nM to about 1 ⁇ M.
  • the antibody when coupled to a compound, has an affinity for the BBB-R from about 50 nM to about 1 ⁇ M.
  • the compound-coupled antibody specifically binds to TfR and has an affinity for TfR between those affinities observed for the anti-TfR A /BACE1 antibody and the anti-TfR E /BACE1 antibody.
  • the compound-coupled antibody specifically binds to TfR and has an affinity for TfR between those affinities observed for the anti-TfR D /BACE1 antibody and the anti-TfR E /BACE1 antibody.
  • the compound-coupled antibody specifically binds to TfR and has an IC50 for TfR between those IC50s observed for the anti-TfR A /BACE1 antibody and the anti-TfR E /BACE1 antibody. In another such aspect, the compound-coupled antibody specifically binds to TfR and has an IC50 for TfR between those IC50s observed for the anti-TfR D /BACE1 antibody and the anti-TfR E /BACE1 antibody. In one aspect, the affinity of the anti-BBB-R or anti-BBB-R/compound for the BBB-R is measured using scatchard analysis.
  • the affinity of the anti-BBB-R or anti-BBB-R/compound for the BBB-R is measured using BIACORE analysis. In another aspect, the affinity of the anti-BBB-R or anti-BBB-R/compound for the BBB-R is measured using a competition ELISA.
  • the dissociation half-life of the antibody from the BBB-R to which it specifically binds is from about 30 seconds to about 30 minutes. In another such aspect, the dissociation half-life is from about 30 seconds to about 20 minutes. In another such aspect, the dissociation half-life is from about 30 seconds to about 10 minutes. In another such aspect, the dissociation half-life is from about 30 seconds to about 5 minutes. In another such aspect, the dissociation half-life is from about 30 seconds to about 3 minutes. In another such aspect, the dissociation half-life is from about 30 seconds to about 2 minutes. In another such aspect, the dissociation half-life is about two minutes. In another such aspect, the dissociation half-life is one minute or less.
  • the compound-coupled antibody specifically binds to TfR and has a dissociation half-life for TfR between those dissociation half-lives observed for the anti-TfR A /BACE1 antibody and the anti-TfR E /BACE1 antibody from their respective binding to TfR.
  • the compound-coupled antibody specifically binds to TfR and has a dissociation half-life for TfR between those dissociation half-lives observed for the anti-TfR D /BACE1 antibody and the anti-TfR E /BACE1 antibody from their respective binding to TfR.
  • the dissociation half-life of the anti-BBB-R or anti-BBB-R/compound for the BBB-R is measured using BIACORE analysis. In another aspect, the dissociation half-life of the anti-BBB-R or anti-BBB-R/compound for the BBB-R is measured using a competition binding assay, such as a competition ELISA.
  • the antibody is selected from a panel of antibodies based upon the affinity of the selected antibody.
  • the antibody is engineered to have the desired affinity.
  • the antibody is generated using any art-known protein engineering methodology including, but not limited to, phage display, yeast display, random mutagenesis, and site-directed mutagenesis.
  • the compound-coupled antibody is administered at a therapeutic dose.
  • the therapeutic dose is a dose that saturates the BBB-R to which the antibody specifically binds.
  • the compound-coupled antibody is administered at a dose and dose frequency that minimizes red blood cell interaction with the compound-coupled antibody while still facilitating compound delivery across the BBB into the CNS at therapeutic levels.
  • the compound is covalently coupled to the antibody.
  • the compound is joined to the antibody by a linker.
  • the linker is cleavable.
  • the linker is not cleavable.
  • the compound is directly linked to the antibody.
  • the antibody is a multispecific antibody and the compound forms one portion of the multispecific antibody.
  • the multispecific antibody comprises a first antigen binding site which binds the BBB-R and a second antigen binding site which binds a brain antigen.
  • the brain antigen is selected from the group consisting of: beta-secretase 1 (BACE1), Abeta, epidermal growth factor receptor (EGFR), human epidermal growth factor receptor 2 (HER2), Tau, apolipoprotein E4 (ApoE4), alpha-synuclein, CD20, huntingtin, prion protein (PrP), leucine rich repeat kinase 2 (LRRK2), parkin, presenilin 1, presenilin 2, gamma secretase, death receptor 6 (DR6), amyloid precursor protein (APP), p75 neurotrophin receptor (p75NTR), interleukin 6 receptor (IL6R), TNF receptor 1 (TNFR1), interleukin 1 beta (IL1 ⁇ ), and caspase 6.
  • BACE1 beta-secretase 1
  • EGFR epidermal growth factor receptor
  • HER2 human epidermal growth factor receptor 2
  • Tau apolipoprotein E4
  • the multispecific antibody binds both TfR and BACE1. In another such aspect, the multispecific antibody binds both TfR and Abeta. In another such aspect, the multispecific antibody is labeled. In another aspect, the compound is reversibly coupled to the antibody such that the compound is released from the antibody concurrent with or after BBB transport.
  • the invention provides an antibody which binds to a blood-brain barrier receptor (BBB-R), wherein the affinity of the antibody for the BBB-R is from about 5 nM to about 50 ⁇ M, and wherein one or more properties of the antibody have been modified to reduce at least one undesired side effect on red blood cells.
  • BBB-R is selected from the group consisting of transferrin receptor (TfR), insulin receptor, insulin-like growth factor receptor (IGF receptor), low density lipoprotein receptor-related protein 8 (LRP8), low density lipoprotein receptor-related protein 1 (LRP1), glucose transporter 1 (Glut1) and heparin-binding epidermal growth factor-like growth factor (HB-EGF).
  • TfR transferrin receptor
  • IGF receptor insulin-like growth factor receptor
  • LRP8 low density lipoprotein receptor-related protein 8
  • LRP1 low density lipoprotein receptor-related protein 1
  • Glut1 glucose transporter 1
  • HB-EGF heparin-binding epiderma
  • the BBB-R is a human BBB-R. In one such aspect, the BBB-R is TfR. In another such aspect, the BBB-R is TfR, and the antibody does not inhibit TfR activity. In another such aspect, the BBB-R is TfR and the antibody does not inhibit the binding of TfR to transferrin.
  • the red blood cells are immature red blood cells.
  • the immature red blood cells are reticulocytes.
  • reduction of reticulocyte levels is accompanied by acute clinical symptoms.
  • one or more properties of the antibody have been modified to reduce the impact of the antibody on reticulocyte levels and/or reduce the severity or presence of acute clinical symptoms in the subject.
  • the affinity of the antibody for the BBB-R is modified, i.e., decreased.
  • the modification of the affinity of the antibody is measured relative to a wild-type antibody of the same isotype not having modified (i.e., decreased) affinity for the BBB-R.
  • the effector function of the antibody Fc region is modified.
  • the effector function has been reduced or eliminated relative to the effector function of a wild-type antibody of the same isotype.
  • the effector function is reduced or eliminated by reduction of glycosylation of the antibody.
  • the glycosylation of the antibody is reduced by production of the antibody in an environment that does not permit wild-type glycosylation.
  • the antibody is produced in a non-mammalian cell production system.
  • the antibody is produced synthetically.
  • the glycosylation of the antibody is reduced by removal of carbohydrate groups already present on the antibody.
  • the glycosylation of the antibody is reduced by modification of the antibody such that wild-type glycosylation does not occur.
  • the Fc region of the antibody comprises a mutation at position 297 such that the wild-type asparagine residue at that position is replaced with another amino acid that interferes with glycosylation at that position.
  • the effector function is reduced or eliminated by modification of the antibody isotype to an isotype that naturally has reduced or eliminated effector function.
  • the Fc region is modified to reduce or eliminate effector function.
  • the effector function is reduced or eliminated by at least one modification of the Fc region.
  • the modification is a point mutation of the Fc region to impair binding to one or more Fc receptors selected from the following positions: 238, 239, 248, 249, 252, 254, 265, 268, 269, 270, 272, 278, 289, 292, 293, 294, 295, 296, 297, 298, 301, 303, 322, 324, 327, 329, 333, 335, 338, 340, 373, 376, 382, 388, 389, 414, 416, 419, 434, 435, 437, 438, and 439.
  • the modification is elimination of some or all of the Fc region.
  • the effector function is reduced or eliminated by deletion of all or a portion of the Fc region, or by engineering the antibody such that it does not include an Fc region competent for effector function.
  • the antibody is selected from a Fab or a single chain antibody.
  • the Fc region and/or the non-Fc region of the antibody is modified to reduce or eliminate activation of the complement pathway by the antibody.
  • the modification is a point mutation of the Fc region to impair binding to C1q selected from the following positions: 270, 322, 329, and 321.
  • the modification is elimination of some or all of the Fc region.
  • complement-triggering function is reduced or eliminated by deletion of all or a portion of the Fc region, or by engineering the antibody such that it does not include an Fc region that engages the complement pathway.
  • the antibody is selected from a Fab or a single chain antibody.
  • the non-Fc region of the antibody is modified to reduce or eliminate activation of the complement pathway by the antibody.
  • the modification is a point mutation of the CH1 region to impair binding to C3.
  • the point mutation is at position 132 (see, e.g., Vidarte et al., (2001) J. Biol. Chem. 276(41): 38217-38223).
  • the antibody is coupled with a therapeutic compound.
  • the compound is a neurological disorder drug.
  • the compound is an imaging agent.
  • the compound is labeled.
  • the antibody is labeled.
  • the antibody does not impair the binding of the BBB-R to one or more of its native ligands.
  • the antibody specifically binds to TfR in such a manner that it does not inhibit binding of the TfR to transferrin.
  • the BBB is in a mammal.
  • the mammal is a human.
  • the mammal has a neurological disorder.
  • the neurological disorder is selected from the group consisting of Alzheimer's disease (AD), stroke, dementia, muscular dystrophy (MD), multiple sclerosis (MS), amyotrophic lateral sclerosis (ALS), cystic fibrosis, Angelman's syndrome, Liddle syndrome, Parkinson's disease, Pick's disease, Paget's disease, cancer, and traumatic brain injury.
  • the BBB is in a human.
  • the antibody has an IC50 for the BBB-R from about 30 nM to about 30 ⁇ M. In another such aspect, the antibody, when coupled to a compound, has an affinity for the BBB-R from about 30 nM to about 1 ⁇ M. In another such aspect, the compound-coupled antibody specifically binds to TfR and has an affinity for TfR between those affinities observed for the anti-TfR A /BACE1 antibody and the anti-TfR E /BACE1 antibody. In another such aspect, the compound-coupled antibody specifically binds to TfR and has an affinity for TfR between those affinities observed for the anti-TfR D /BACE1 antibody and the anti-TfR E /BACE1 antibody.
  • the compound-coupled antibody specifically binds to TfR and has an IC50 for TfR between those IC50s observed for the anti-TfR A /BACE1 antibody and the anti-TfR E /BACE1 antibody. In another such aspect, the compound-coupled antibody specifically binds to TfR and has an IC50 for TfR between those IC50s observed for the anti-TfR D /BACE1 antibody and the anti-TfR E /BACE1 antibody. In one aspect, the affinity of the anti-BBB-R or anti-BBB-R/compound for the BBB-R is measured using scatchard analysis.
  • the affinity of the anti-BBB-R or anti-BBB-R/compound for the BBB-R is measured using BIACORE analysis. In another aspect, the affinity of the anti-BBB-R or anti-BBB-R/compound for the BBB-R is measured using a competition ELISA.
  • the dissociation half-life of the antibody from the BBB-R to which it specifically binds is from about 30 seconds to about 30 minutes. In another such aspect, the dissociation half-life is from about 30 seconds to about 20 minutes. In another such aspect, the dissociation half-life is from about 30 seconds to about 10 minutes. In another such aspect, the dissociation half-life is from about 30 seconds to about 5 minutes. In another such aspect, the dissociation half-life is from about 30 seconds to about 3 minutes. In another such aspect, the dissociation half-life is from about 30 seconds to about 2 minutes. In another such aspect, the dissociation half-life is about two minutes. In another such aspect, the dissociation half-life is one minute or less.
  • the compound-coupled antibody specifically binds to TfR and has a dissociation half-life for TfR between those dissociation half-lives observed for the anti-TfR A /BACE1 antibody and the anti-TfR E /BACE1 antibody from their respective binding to TfR.
  • the compound-coupled antibody specifically binds to TfR and has a dissociation half-life for TfR between those dissociation half-lives observed for the anti-TfR D /BACE1 antibody and the anti-TfR E /BACE1 antibody from their respective binding to TfR.
  • the dissociation half-life of the anti-BBB-R or anti-BBB-R/compound for the BBB-R is measured using BIACORE analysis. In another aspect, the dissociation half-life of the anti-BBB-R or anti-BBB-R/compound for the BBB-R is measured using a competition binding assay, such as a competition ELISA.
  • the antibody is selected from a panel of antibodies based upon the affinity of the selected antibody.
  • the antibody is engineered to have the desired affinity.
  • the antibody is generated using any art-known protein engineering methodology including, but not limited to, phage display, yeast display, random mutagenesis, and site-directed mutagenesis.
  • a compound is covalently coupled to the antibody.
  • the compound is joined to the antibody by a linker.
  • the linker is cleavable.
  • the linker is not cleavable.
  • the compound is directly linked to the antibody.
  • the antibody is a multispecific antibody and the compound forms one portion of the multispecific antibody.
  • the multispecific antibody comprises a first antigen binding site which binds the BBB-R and a second antigen binding site which binds a brain antigen.
  • the brain antigen is selected from the group consisting of: beta-secretase 1 (BACE1), Abeta, epidermal growth factor receptor (EGFR), human epidermal growth factor receptor 2 (HER2), Tau, apolipoprotein E4 (ApoE4), alpha-synuclein, CD20, huntingtin, prion protein (PrP), leucine rich repeat kinase 2 (LRRK2), parkin, presenilin 1, presenilin 2, gamma secretase, death receptor 6 (DR6), amyloid precursor protein (APP), p75 neurotrophin receptor (p75NTR), interleukin 6 receptor (IL6R), TNF receptor 1 (TNFR1), interleukin 1 beta (IL1 ⁇ ), and caspase 6.
  • BACE1 beta-secretase 1
  • EGFR epidermal growth factor receptor
  • HER2 human epidermal growth factor receptor 2
  • Tau apolipoprotein E4
  • the multispecific antibody binds both TfR and BACE1. In another such aspect, the multispecific antibody binds both TfR and Abeta. In another such aspect, the multispecific antibody is labeled. In another aspect, the compound is reversibly coupled to the antibody such that the compound is released from the antibody concurrent with or after BBB transport.
  • the invention provides the use of an antibody that binds with low affinity to a BBB-R and that does not reduce red blood cell levels for the manufacture of a medicament for treating a neurological disorder.
  • an antibody that binds with low affinity to a BBB-R and that does not reduce red blood cell levels for the manufacture of a medicament for treating a neurological disorder.
  • Any of the foregoing described low-affinity anti-BBB-R antibodies or any of the low-affinity anti-BBB-R antibodies described elsewhere herein may be used in the method.
  • the invention provides an antibody that binds with low affinity to a BBB-R and that does not reduce red blood cell levels for use in treating a neurological disorder.
  • Any of the foregoing described low-affinity anti-BBB-R antibodies or any of the low-affinity anti-BBB-R antibodies described elsewhere herein may be used in the method.
  • the invention provides a method of transporting a therapeutic compound, such as a neurological disorder drug, across the blood-brain barrier comprising exposing the anti-BBB-R antibody coupled with a neurological disorder drug to the blood-brain barrier such that the antibody transports the neurological disorder drug coupled thereto across the blood-brain barrier, wherein the antibody does not reduce red blood cell levels.
  • a therapeutic compound such as a neurological disorder drug
  • the invention additionally provides a method of treating a neurological disorder in a mammal comprising treating the mammal with a multispecific antibody that binds both a blood-brain barrier receptor (BBB-R) and a brain antigen, wherein the anti-BBB-R antibody has been selected to have a low affinity for the BBB-R and thereby improves brain uptake of the anti-brain antigen antibody, and wherein administration of the antibody does not decrease red blood cell levels.
  • BBB-R blood-brain barrier receptor
  • the invention additionally provides a method of treating a disease or disorder associated with or caused by elevated red blood cell levels in a subject comprising administering an anti-TfR antibody comprising at least partial effector function to the subject.
  • the administering step is at a dose and/or dose frequency calibrated to minimize acute clinical symptoms of the antibody administration.
  • FIGS. 1A-1E depict the results of experiments assessing the affinities of anti-transferrin receptor (“TfR”) and anti-TfR/beta-secretase (“BACE1”) variants for TfR, as well as concentrations of the antibody and A ⁇ 1-40 after administration in mice, as described in Example 1.
  • the competitive ELISA assay results in FIG. 1A show that anti-TfR/BACE1 variants and anti-TfR variants have distinct affinities for TfR.
  • FIGS. 1C and 1E show, respectively, plasma and brain concentrations of A ⁇ 1-40 in these same treated mice, as a marker of the activity of the injected antibody.
  • FIG. 2A is a schematic depiction of red blood cell (RBC) maturation in the bone marrow, showing progression from the pro-erythroblast (Pro-EB), to basophilic erythroblast (Baso-EB), to polychromatic erythroblast (Poly-EB), to orthochromatic erythroblast (Ortho-EB) and finally to the reticulocyte.
  • Reticulocytes are released from the bone marrow to the circulation where they mature to RBCs.
  • erythroid precursors synthesize the iron-containing protein hemoglobin, which requires a concomitant increase in TfR expression.
  • Transferrin receptors are shed with the cessation of hemoglobin synthesis and cell proliferation as cells mature through the reticulocyte stage, such that mature RBCs do not express TfR.
  • the relative number of TfR present at each cell stage of RBC maturation is indicated in the graph at the top of the figure, based on data from Iacpetta et al., Biochim. Biophys. Acta 687: 204-210 (1982).
  • FIGS. 2B and 2C depict the results of experiments assessing the impact of anti-TfR and anti-TfR/BACE1 administration on reticulocytes in mice, as described in Example 2A.
  • FIGS. 2F-2H depict the results of experiments assessing the pharmacokinetics of anti-TfR A /BACE1 and anti-TfR D /BACE1 in comparison with control at 5 mg/kg, 25 mg/kg or 50 mg/kg dose levels.
  • FIG. 2F provides measurements of brain antibody concentration at the indicated time points.
  • FIG. 2G provides measurements of plasma antibody concentration at the indicated time points.
  • FIG. 2H provides measurements of plasma Abeta levels at the indicated time points.
  • FIGS. 3A-3E depict the results of experiments assessing the impact of elimination of effector function ( FIGS. 3A-3C ) or elimination of complement function ( FIGS. 3D and 3E ) on reticulocyte depletion by various anti-TfR antibodies, as described in Example 2B.
  • FIG. 3A and 3C wild-type mice
  • Fc ⁇ ⁇ / ⁇ B6.129P2-Fcer1gtm1Rav N12 mice
  • FIG. 3D C3 ⁇ / ⁇ mice
  • 3E depicts the results of experiments assessing the effect of impairment of the complement system on the previously observed depletion of reticulocytes by anti-TfR.
  • FIGS. 4A and 4B depict the results of in vitro experiments assessing the induction of antibody-dependent cell-mediated cytotoxicity (ADCC) ( FIG. 4A ) or complement-dependent cytotoxicity (CDC) ( FIG. 4B ) by anti-TfR A , anti-TfR A /BACE1, or control IgG in mouse erythroleukemic blasts at a range of antibody concentrations, as described in Example 2B.
  • ADCC antibody-dependent cell-mediated cytotoxicity
  • CDC complement-dependent cytotoxicity
  • FIGS. 5A-5C depict the results of experiments assessing whether elimination of Fc binding or BACE1 binding impacts reticulocyte depletion by monospecific or bispecific anti-TfR antibodies, as described in Example 2C.
  • FIGS. 6A-6C depict the results of experiments assessing the impact of reducing affinity to TfR on reticulocyte depletion and brain TfR expression, as described in Example 3.
  • FIGS. 6A and 6B depict total reticulocyte counts in wild-type mice 24 hours after intravenous injection of the indicated anti-TfR/BACE1 variant antibody, compared to control IgG.
  • FIGS. 8A-8F depict the results of experiments assessing the impact of multiple doses of anti-TfR D /BACE1 on reticulocyte levels in treated mice, as described in Example 5.
  • Wild-type mice were intravenously dosed once weekly with 25 mg/kg of control IgG or anti-TfR D /BACE1.
  • FIGS. 8A and 8B respectively, depict observed plasma and brain antibody concentrations at 24 hours, 4 days and 7 days following two or four doses of antibody.
  • the Y-axis scale in FIG. 8A is in ⁇ M while the Y-axis scale in FIG. 8B is in nM.
  • the corresponding average A ⁇ 1-40 concentrations in plasma ( FIG. 8C ) and brain ( FIG. 8D ) were also measured.
  • FIG. 8E shows the total reticulocyte count in mice 24 hours after the second and fourth dose, and 7 days after the fourth dose of control IgG or anti-TfR D /BACE1.
  • FIG. 8F shows a graph depicting the results of a quantification of brain TfR expression level by Western blot from whole mouse brain lysates after 4 weekly doses of control IgG or anti-TfR D /BACE1. Quantification of TfR expression was normalized to actin and data are shown as mean ⁇ SEM.
  • FIGS. 9A-9B and 10 A- 10 D depict the results of experiments assessing the impact of an effectorless anti-TfR/BACE1 antibody on erythrocyte subpopulations in blood and bone marrow in mice. Distinct populations of Ter119-positive erythrocyte lineage in both ( FIG. 9A ) blood and ( FIG. 9B ) bone marrow are distinguished by their TfR expression and cell size (as determined by forward scatter profile) using flow cytometry (Paniga et al., PLoS One 6, 9 (2011)).
  • FIGS. 11A-11B and 12 A- 12 D depict the results of experiments analyzing the impact of affinity and effector function of an anti-TfR/BACE1 antibody on erythrocyte populations in blood and bone marrow in mice.
  • FIGS. 13A-B and FIGS. 14A-B depict the results of experiments assessing the impact of effector function status on ADCC activity of anti-human TfR (“anti-hTFR”) antibodies in a human erythroblast cell line or primary human bone marrow mononuclear cells, as described in Example 7.
  • anti-hTFR anti-human TfR
  • FIGS. 15A-B depict the light and heavy chain amino acid sequences of anti-BACE1 clone YW412.8 obtained from a na ⁇ ve sort of the natural diversity phage display library and affinity-matured forms of YW412.8.
  • FIG. 15A depicts the variable light (VL) sequence alignments (SEQ ID NOs. 1-6).
  • FIG. 13B depicts the variable heavy (VH) sequence alignments (SEQ ID Nos. 7-8).
  • the HVR sequences for each clone are indicated by the boxed regions, with the first box indicating HVR-L1 ( FIG. 15A ) or HVR-H1 ( FIG. 15B ), the second box indicating HVR-L2 ( FIG. 15A ) or HVR-H2 ( FIG. 15B ), and the third box indicating HVR-L3 ( FIG. 15A ) or HVR-H3 ( FIG. 15B ).
  • FIGS. 16A-B depict the light and heavy chain amino acid sequences of anti-BACE1 antibody clone Fab 12 obtained from a na ⁇ ve sort of a synthetic diversity phage display library and affinity-matured forms of Fab 12.
  • FIG. 16A depicts the light chain sequence alignments (SEQ ID NOs. 9-12).
  • FIG. 16B depicts the heavy chain sequence alignments (SEQ ID NO. 13).
  • the HVR sequences for each clone are indicated by the boxed regions, with the first box indicating HVR-L1 ( FIG. 16A ) or HVR-H1 ( FIG. 16B ), the second box indicating HVR-L2 ( FIG. 16A ) or HVR-H2 ( FIG. 16B ), and the third box indicating HVR-L3 ( FIG. 16A ) or HVR-H3 ( FIG. 16B ).
  • FIGS. 17A-B depict the heavy chain ( FIG. 17A ; SEQ ID NO. 14) and light chain ( FIG. 17B ; SEQ ID NO. 15) of an exemplary anti-Abeta antibody.
  • the “blood-brain barrier” or “BBB” refers to the physiological barrier between the peripheral circulation and the brain and spinal cord (i.e., the CNS) which is formed by tight junctions within the brain capillary endothelial plasma membranes, creating a tight barrier that restricts the transport of molecules into the brain, even very small molecules such as urea (60 Daltons).
  • the blood-brain barrier within the brain, the blood-spinal cord barrier within the spinal cord, and the blood-retinal barrier within the retina are contiguous capillary barriers within the CNS, and are herein collectively referred to a the blood-brain barrier or BBB.
  • the BBB also encompasses the blood-CSF barrier (choroid plexus) where the barrier is comprised of ependymal cells rather than capillary endothelial cells.
  • central nervous system or “CNS” refers to the complex of nerve tissues that control bodily function, and includes the brain and spinal cord.
  • BBB-R blood-brain barrier receptor
  • IGF-R insulin-like growth factor receptor
  • LRP1 low density lipoprotein receptors
  • LRP8 glucose transporter 1
  • HB-EGF heparin-binding epidermal growth factor-like growth factor
  • TfR transferrin receptor
  • TfR transferrin receptor
  • the “transferrin receptor” (“TfR”) is a transmembrane glycoprotein (with a molecular weight of about 180,000) composed of two disulphide-bonded sub-units (each of apparent molecular weight of about 90,000) involved in iron uptake in vertebrates.
  • the TfR herein is human TfR comprising the amino acid sequence as set forth in Schneider et al. Nature 311: 675-678 (1984), for example.
  • a “neurological disorder” as used herein refers to a disease or disorder which affects the CNS and/or which has an etiology in the CNS.
  • Exemplary CNS diseases or disorders include, but are not limited to, neuropathy, amyloidosis, cancer, an ocular disease or disorder, viral or microbial infection, inflammation, ischemia, neurodegenerative disease, seizure, behavioral disorders, and a lysosomal storage disease.
  • the CNS will be understood to include the eye, which is normally sequestered from the rest of the body by the blood-retina barrier.
  • neurological disorders include, but are not limited to, neurodegenerative diseases (including, but not limited to, Lewy body disease, postpoliomyelitis syndrome, Shy-Draeger syndrome, olivopontocerebellar atrophy, Parkinson's disease, multiple system atrophy, striatonigral degeneration, tauopathies (including, but not limited to, Alzheimer disease and supranuclear palsy), prion diseases (including, but not limited to, bovine spongiform encephalopathy, scrapie, Creutzfeldt-Jakob syndrome, kuru, Gerstmann-Straussler-Scheinker disease, chronic wasting disease, and fatal familial insomnia), bulbar palsy, motor neuron disease, and nervous system heterodegenerative disorders (including, but not limited to, Canavan disease, Huntington's disease, neuronal ceroid-lipofuscinosis, Alexander's disease, Tourette's syndrome, Menkes kinky hair syndrome, Cockayne syndrome, Halervorden-Spatz syndrome, la
  • Neurological disorder drug is a drug or therapeutic agent that treats one or more neurological disorder(s).
  • Neurological disorder drugs of the invention include, but are not limited to, antibodies, peptides, proteins, natural ligands of one or more CNS target(s), modified versions of natural ligands of one or more CNS target(s), aptamers, inhibitory nucleic acids (i.e., small inhibitory RNAs (siRNA) and short hairpin RNAs (shRNA)), ribozymes, and small molecules, or active fragments of any of the foregoing.
  • siRNA small inhibitory RNAs
  • shRNA short hairpin RNAs
  • Exemplary neurological disorder drugs of the invention include, but are not limited to: antibodies, aptamers, proteins, peptides, inhibitory nucleic acids and small molecules and active fragments of any of the foregoing that either are themselves or specifically recognize and/or act upon (i.e., inhibit, activate, or detect) a CNS antigen or target molecule such as, but not limited to, amyloid precursor protein or portions thereof, amyloid beta, beta-secretase, gamma-secretase, tau, alpha-synuclein, parkin, huntingtin, DR6, presenilin, ApoE, glioma or other CNS cancer markers, and neurotrophins
  • Table 1 Non-limiting examples of neurological disorder drugs and the disorders they may be used to treat are provided in the following Table 1:
  • cancer Anti-VEGF antibody e.g., bevacizumab
  • imaging agent is a compound that has one or more properties that permit its presence and/or location to be detected directly or indirectly.
  • imaging agents include proteins and small molecule compounds incorporating a labeled moiety that permits detection.
  • a “CNS antigen” or “brain antigen” is an antigen expressed in the CNS, including the brain, which can be targeted with an antibody or small molecule.
  • antigens include, without limitation: beta-secretase 1 (BACE1), amyloid beta (Abeta), epidermal growth factor receptor (EGFR), human epidermal growth factor receptor 2 (HER2), tau, apolipoprotein E4 (ApoE4), alpha-synuclein, CD20, huntingtin, prion protein (PrP), leucine rich repeat kinase 2 (LRRK2), parkin, presenilin 1, presenilin 2, gamma secretase, death receptor 6 (DR6), amyloid precursor protein (APP), p75 neurotrophin receptor (p75NTR), interleukin 6 receptor (IL6R), TNF receptor 1 (TNFR1), interleukin 1 beta (IL1 ⁇ ), and caspase 6.
  • BACE1 beta-secretase 1
  • BACE1 refers to any native beta-secretase 1 (also called ⁇ -site amyloid precursor protein cleaving enzyme 1, membrane-associated aspartic protease 2, memapsin 2, aspartyl protease 2 or Asp2) from any vertebrate source, including mammals such as primates (e.g. humans) and rodents (e.g., mice and rats), unless otherwise indicated.
  • the term encompasses “full-length,” unprocessed BACE1 as well as any form of BACE1 which results from processing in the cell.
  • the term also encompasses naturally occurring variants of BACE1, e.g., splice variants or allelic variants.
  • the amino acid sequence of an exemplary BACE1 polypeptide is the sequence for human BACE1, isoform A as reported in Vassar et al., Science 286:735-741 (1999), which is incorporated herein by reference in its entirety.
  • isoforms of human BACE1 exist including isoforms B, C and D. See UniProtKB/Swiss-Prot Entry P56817, which is incorporated herein by reference in its entirety.
  • anti-beta-secretase antibody refers to an antibody that is capable of binding BACE1 with sufficient affinity such that the antibody is useful as a diagnostic and/or therapeutic agent in targeting BACE1.
  • the extent of binding of an anti-BACE1 antibody to an unrelated, non-BACE1 protein is less than about 10% of the binding of the antibody to BACE1 as measured, e.g., by a radioimmunoassay (RIA).
  • an antibody that binds to BACE1 has a dissociation constant (Kd) of ⁇ 1 ⁇ M, ⁇ 100 nM, ⁇ 10 nM, ⁇ 1 nM, ⁇ 0.1 nM, ⁇ 0.01 nM, or ⁇ 0.001 nM (e.g. 10 ⁇ 8 M or less, e.g. from 10 ⁇ 8 M to 10 ⁇ 13 M, e.g., from 10 ⁇ 9 M to 10 ⁇ 13 M).
  • Kd dissociation constant
  • an anti-BACE1 antibody binds to an epitope of BACE1 that is conserved among BACE1 from different species and isoforms.
  • an antibody that binds to the epitope on BACE1 bound by anti-BACE1 antibody YW412.8.31. In other embodiments, an antibody is provided that binds to an exosite within BACE1 located in the catalytic domain of BACE1. In one embodiment an antibody is provided that competes with the peptides identified in Kornacker et al., Biochem.
  • a “native sequence” protein herein refers to a protein comprising the amino acid sequence of a protein found in nature, including naturally occurring variants of the protein.
  • the term as used herein includes the protein as isolated from a natural source thereof or as recombinantly produced.
  • antibody herein is used in the broadest sense and specifically covers monoclonal antibodies, polyclonal antibodies, multispecific antibodies (e.g. bispecific antibodies) formed from at least two intact antibodies, and antibody fragments so long as they exhibit the desired biological activity.
  • Antibody fragments herein comprise a portion of an intact antibody which retains the ability to bind antigen.
  • Examples of antibody fragments are well known in the art (see, e.g., Nelson, MAbs (2010) 2(1): 77-83) and include but are not limited to Fab, Fab′, F(ab′) 2 , and Fv fragments; diabodies; linear antibodies; single-chain antibody molecules including but not limited to single-chain variable fragments (scFv), fusions of light and/or heavy-chain antigen-binding domains with or without a linker (and optionally in tandem); and monospecific or multispecific antigen-binding molecules formed from antibody fragments (including, but not limited to multispecific antibodies constructed from multiple variable domains which lack Fc regions).
  • the term “monoclonal antibody” as used herein refers to an antibody obtained from a population of substantially homogeneous antibodies, i.e., the individual antibodies comprising the population are identical and/or bind the same epitope, except for possible variants that may arise during production of the monoclonal antibody, such variants generally being present in minor amounts.
  • each monoclonal antibody is directed against a single determinant on the antigen.
  • the monoclonal antibodies are advantageous in that they are uncontaminated by other immunoglobulins.
  • the modifier “monoclonal” indicates the character of the antibody as being obtained from a substantially homogeneous population of antibodies, and is not to be construed as requiring production of the antibody by any particular method.
  • the monoclonal antibodies to be used in accordance with the present invention may be made by the hybridoma method first described by Kohler et al., Nature, 256:495 (1975), or may be made by recombinant DNA methods (see, e.g., U.S. Pat. No. 4,816,567).
  • the “monoclonal antibodies” may also be isolated from phage antibody libraries using the techniques described in Clackson et al., Nature, 352:624-628 (1991) and Marks et al., J. Mol. Biol., 222:581-597 (1991), for example.
  • Specific examples of monoclonal antibodies herein include chimeric antibodies, humanized antibodies, and human antibodies, including antigen-binding fragments thereof.
  • the monoclonal antibodies herein specifically include “chimeric” antibodies (immunoglobulins) in which a portion of the heavy and/or light chain is identical with or homologous to corresponding sequences in antibodies derived from a particular species or belonging to a particular antibody class or subclass, while the remainder of the chain(s) is identical with or homologous to corresponding sequences in antibodies derived from another species or belonging to another antibody class or subclass, as well as fragments of such antibodies, so long as they exhibit the desired biological activity (U.S. Pat. No. 4,816,567; Morrison et al., Proc. Natl. Acad. Sci. USA, 81:6851-6855 (1984)).
  • chimeric antibodies immunoglobulins in which a portion of the heavy and/or light chain is identical with or homologous to corresponding sequences in antibodies derived from a particular species or belonging to a particular antibody class or subclass, while the remainder of the chain(s) is identical with or homologous to corresponding sequences
  • Chimeric antibodies of interest herein include “primatized” antibodies comprising variable domain antigen-binding sequences derived from a non-human primate (e.g. Old World Monkey, such as baboon, rhesus or cynomolgus monkey) and human constant region sequences (U.S. Pat. No. 5,693,780).
  • a non-human primate e.g. Old World Monkey, such as baboon, rhesus or cynomolgus monkey
  • human constant region sequences U.S. Pat. No. 5,693,780
  • “Humanized” forms of non-human (e.g., murine) antibodies are chimeric antibodies that contain minimal sequence derived from non-human immunoglobulin.
  • humanized antibodies are human immunoglobulins (recipient antibody) in which residues from a hypervariable region of the recipient are replaced by residues from a hypervariable region of a non-human species (donor antibody) such as mouse, rat, rabbit or nonhuman primate having the desired specificity, affinity, and capacity.
  • donor antibody such as mouse, rat, rabbit or nonhuman primate having the desired specificity, affinity, and capacity.
  • framework region (FR) residues of the human immunoglobulin are replaced by corresponding non-human residues.
  • humanized antibodies may comprise residues that are not found in the recipient antibody or in the donor antibody. These modifications are made to further refine antibody performance.
  • the humanized antibody will comprise substantially all of at least one, and typically two, variable domains, in which all or substantially all of the hypervariable regions correspond to those of a non-human immunoglobulin and all or substantially all of the FRs are those of a human immunoglobulin sequence, except for FR substitution(s) as noted above.
  • the humanized antibody optionally also will comprise at least a portion of an immunoglobulin constant region, typically that of a human immunoglobulin. For further details, see Jones et al., Nature 321:522-525 (1986); Riechmann et al., Nature 332:323-329 (1988); and Presta, Curr. Op. Struct. Biol. 2:593-596 (1992).
  • a “human antibody” herein is one comprising an amino acid sequence structure that corresponds with the amino acid sequence structure of an antibody obtainable from a human B-cell, and includes antigen-binding fragments of human antibodies.
  • Such antibodies can be identified or made by a variety of techniques, including, but not limited to: production by transgenic animals (e.g., mice) that are capable, upon immunization, of producing human antibodies in the absence of endogenous immunoglobulin production (see, e.g., Jakobovits et al., Proc. Natl. Acad. Sci.
  • a “multispecific antibody” herein is an antibody having binding specificities for at least two different epitopes.
  • Exemplary multispecific antibodies may bind both a BBB-R and a brain antigen.
  • Multispecific antibodies can be prepared as full-length antibodies or antibody fragments (e.g. F(ab′) 2 bispecific antibodies).
  • Engineered antibodies with two, three or more (e.g. four) functional antigen binding sites are also contemplated (see, e.g., US Appln No. US 2002/0004587 A1, Miller et al.).
  • Multispecific antibodies can be prepared as full length antibodies or as antibody fragments.
  • Antibodies herein include “amino acid sequence variants” with altered antigen-binding or biological activity.
  • amino acid alterations include antibodies with enhanced affinity for antigen (e.g. “affinity matured” antibodies), and antibodies with altered Fc region, if present, e.g. with altered (increased or diminished) antibody dependent cellular cytotoxicity (ADCC) and/or complement dependent cytotoxicity (CDC) (see, for example, WO 00/42072, Presta, L. and WO 99/51642, Iduosogie et al.); and/or increased or diminished serum half-life (see, for example, WO00/42072, Presta, L.).
  • ADCC antibody dependent cellular cytotoxicity
  • CDC complement dependent cytotoxicity
  • an “affinity modified variant” has one or more substituted hypervariable region or framework residues of a parent antibody (e.g. of a parent chimeric, humanized, or human antibody) that alter (increase or reduce) affinity.
  • a parent antibody e.g. of a parent chimeric, humanized, or human antibody
  • a convenient way for generating such substitutional variants uses phage display. Briefly, several hypervariable region sites (e.g. 6-7 sites) are mutated to generate all possible amino substitutions at each site. The antibody variants thus generated are displayed in a monovalent fashion from filamentous phage particles as fusions to the gene III product of M13 packaged within each particle. The phage-displayed variants are then screened for their biological activity (e.g. binding affinity).
  • alanine scanning mutagenesis can be performed to identify hypervariable region residues contributing significantly to antigen binding.
  • a “pH-sensitive antibody variant” is an antibody variant which has a different binding binding affinity for a target antigen at a first pH than it does for that target antigen at a different pH.
  • an anti-TfR antibody of the invention may be selected for or engineered to have pH-sensitive binding to TfR such that it binds with desirably low affinity (as described herein) to cell surface TfR in the plasma at pH 7.4, but upon internalization into an endosomal compartment, rapidly dissociates from TfR at the relatively lower pH (pH 5.5-6.0); such dissociation may protect the antibody from antigen-mediated clearance, and increase the amount of antibody that is either delivered to the CNS or recycled back across the BBB—in either case, the effective concentration of the antibody is increased relative to an anti-TfR antibody that does not comprise such pH sensitivity (see, e.g., Chaparro-Riggers et al.
  • the antibody herein may be conjugated with a “heterologous molecule” for example to increase half-life or stability or otherwise improve the antibody.
  • the antibody may be linked to one of a variety of non-proteinaceous polymers, e.g., polyethylene glycol (PEG), polypropylene glycol, polyoxyalkylenes, or copolymers of polyethylene glycol and polypropylene glycol.
  • Antibody fragments, such as Fab′, linked to one or more PEG molecules are an exemplary embodiment of the invention.
  • the heterologous molecule is a therapeutic compound or a visualization agent (ie., a detectable label), and the antibody is being used to transport such heterologous molecule across the BBB.
  • heterologous molecules include, but are not limited to, a chemical compound, a peptide, a polymer, a lipid, a nucleic acid, and a protein.
  • the antibody herein may be a “glycosylation variant” such that any carbohydrate attached to the Fc region, if present, is altered, either modified in presence/absence, or modified in type.
  • a “glycosylation variant” such that any carbohydrate attached to the Fc region, if present, is altered, either modified in presence/absence, or modified in type.
  • antibodies with a mature carbohydrate structure that lacks fucose attached to an Fc region of the antibody are described in US Pat Appl No US 2003/0157108 (Presta, L.). See also US 2004/0093621 (Kyowa Hakko Kogyo Co., Ltd).
  • Antibodies with a bisecting N-acetylglucosamine (GlcNAc) in the carbohydrate attached to an Fc region of the antibody are referenced in WO 2003/011878, Jean-Mairet et al. and U.S. Pat.
  • hypervariable region when used herein refers to the amino acid residues of an antibody that are responsible for antigen binding.
  • the hypervariable region comprises amino acid residues from a “complementarity determining region” or “CDR” (e.g. residues 24-34 (L1), 50-56 (L2) and 89-97 (L3) in the light chain variable domain and 31-35 (H1), 50-65 (H2) and 95-102 (H3) in the heavy chain variable domain; Kabat et al., Sequences of Proteins of Immunological Interest, 5th Ed. Public Health Service, National Institutes of Health, Bethesda, Md. (1991)) and/or those residues from a “hypervariable loop” (e.g.
  • “Framework” or “FR” residues are those variable domain residues other than the hypervariable region residues as herein defined.
  • a “full length antibody” is one which comprises an antigen-binding variable region as well as a light chain constant domain (CL) and heavy chain constant domains, CH1, CH2 and CH3.
  • the constant domains may be native sequence constant domains (e.g. human native sequence constant domains) or amino acid sequence variants thereof.
  • naked antibody is an antibody (as herein defined) that is not conjugated to a heterologous molecule, such as a cytotoxic moiety, polymer, or radiolabel.
  • Antibody effector functions refer to those biological activities of an antibody that result in activation of the immune system other than activation of the complement pathway. Such activities are largely found in the Fc region (a native sequence Fc region or amino acid sequence variant Fc region) of an antibody. Examples of antibody effector functions include, for example, Fc receptor binding and antibody-dependent cell-mediated cytotoxicity (ADCC). In one embodiment, the antibody herein essentially lacks effector function. In another embodiment, the antibody herein retains minimal effector function.
  • Methods of modifying or eliminating effector function include, but are not limited to, eliminating all or a portion of the Fc region responsible for the effector function (ie, using an antibody or antibody fragment in a format lacking all or a portion of the Fc region such as, but not limited to, a Fab fragment, a single-chain antibody, and the like as described herein and as known in the art; modifying the Fc region at one or more amino acid positions to eliminate effector function (Fc binding-impacting: positions 238, 239, 248, 249, 252, 254, 265, 268, 269, 270, 272, 278, 289, 292, 293, 294, 295, 296, 297, 298, 301, 303, 322, 324, 327, 329, 333, 335, 338, 340, 373, 376, 382, 388, 389, 414, 416, 419, 434, 435, 437, 438, and 439; and modifying the glycosylation of the Fc region responsible for the effect
  • Antibody “complement activation” functions, or properties of an antibody that enable or trigger “activation of the complement pathway” are used interchangeably, and refer to those biological activities of an antibody that engage or stimulate the complement pathway of the immune system in a subject. Such activities include, e.g., C1q binding and complement dependent cytotoxicity (CDC), and may be mediated by both the Fc portion and the non-Fc portion of the antibody.
  • C1q binding and complement dependent cytotoxicity CDC
  • Methods of modifying or eliminating complement activation function include, but are not limited to, eliminating all or a portion of the Fc region responsible for complement activation (ie., using an antibody or antibody fragment in a format lacking all or a portion of the Fc region such as, but not limited to, a Fab fragment, a single-chain antibody, and the like as described herein and as known in the art, or modifying the Fc region at one or more amino acid positions to eliminate or lessen interactions with complement components or the ability to activate complement components, such as positions 270, 322, 329 and 321, known to be involved in C1q binding), and modifying or eliminating a portion of the non-Fc region responsible for complement activation (ie, modifying the CH1 region at position 132 (see, e.g., Vidarte et al., (2001) J. Biol. Chem. 276(41): 38217-38223)).
  • full length antibodies can be assigned to different “classes”. There are five major classes of full length antibodies: IgA, IgD, IgE, IgG, and IgM, and several of these may be further divided into “subclasses” (isotypes), e.g., IgG1, IgG2, IgG3, IgG4, IgA, and IgA2.
  • the heavy-chain constant domains that correspond to the different classes of antibodies are called alpha, delta, epsilon, gamma, and mu, respectively.
  • the subunit structures and three-dimensional configurations of different classes of immunoglobulins are well known.
  • recombinant antibody refers to an antibody (e.g. a chimeric, humanized, or human antibody or antigen-binding fragment thereof) that is expressed by a recombinant host cell comprising nucleic acid encoding the antibody.
  • host cells for producing recombinant antibodies include: (1) mammalian cells, for example, Chinese Hamster Ovary (CHO), COS, myeloma cells (including Y0 and NS0 cells), baby hamster kidney (BHK), Hela and Vero cells; (2) insect cells, for example, sf9, sf21 and Tn5; (3) plant cells, for example plants belonging to the genus Nicotiana (e.g.
  • Nicotiana tabacum (4) yeast cells, for example, those belonging to the genus Saccharomyces (e.g. Saccharomyces cerevisiae ) or the genus Aspergillus (e.g. Aspergillus niger ); (5) bacterial cells, for example Escherichia coli cells or Bacillus subtilis cells, etc.
  • yeast cells for example, those belonging to the genus Saccharomyces (e.g. Saccharomyces cerevisiae ) or the genus Aspergillus (e.g. Aspergillus niger );
  • bacterial cells for example Escherichia coli cells or Bacillus subtilis cells, etc.
  • binding affinity refers to an antibody selectively or preferentially binding to an antigen.
  • the binding affinity is generally determined using a standard assay, such as Scatchard analysis, or surface plasmon resonance technique (e.g. using BIACORE®).
  • an “antibody that binds to the same epitope” as a reference antibody refers to an antibody that blocks binding of the reference antibody to its antigen in a competition assay by 50% or more, and conversely, the reference antibody blocks binding of the antibody to its antigen in a competition assay by 50% or more.
  • an anti-BACE1 antibody binds to the BACE1 epitope bound by YW412.8.31.
  • cytotoxic agent refers to a substance that inhibits or prevents a cellular function and/or causes cell death or destruction.
  • Cytotoxic agents include, but are not limited to, radioactive isotopes (e.g., At 211 , I 131 , I 125 , Y 90 , Re 186 , Re 188 , Sm 153 , Bi 212 , P 32 , Pb 212 and radioactive isotopes of Lu); chemotherapeutic agents or drugs (e.g., methotrexate, adriamicin, vinca alkaloids (vincristine, vinblastine, etoposide), doxorubicin, melphalan, mitomycin C, chlorambucil, daunorubicin or other intercalating agents); growth inhibitory agents; enzymes and fragments thereof such as nucleolytic enzymes; antibiotics; toxins such as small molecule toxins or enzymatically active toxins of bacterial, fungal
  • an “effective amount” of an agent refers to an amount effective, at dosages and for periods of time necessary, to achieve the desired therapeutic or prophylactic result.
  • Fc region herein is used to define a C-terminal region of an immunoglobulin heavy chain that contains at least a portion of the constant region.
  • the term includes native sequence Fc regions and variant Fc regions.
  • a human IgG heavy chain Fc region extends from Cys226, or from Pro230, to the carboxyl-terminus of the heavy chain.
  • the C-terminal lysine (Lys447) of the Fc region may or may not be present.
  • numbering of amino acid residues in the Fc region or constant region is according to the EU numbering system, also called the EU index, as described in Kabat et al., Sequences of Proteins of Immunological Interest, 5th Ed. Public Health Service, National Institutes of Health, Bethesda, Md., 1991.
  • “Framework” or “FR” refers to variable domain residues other than hypervariable region (HVR) residues.
  • the FR of a variable domain generally consists of four FR domains: FR1, FR2, FR3, and FR4. Accordingly, the HVR and FR sequences generally appear in the following sequence in VH (or VL): FR1-H1(L1)-FR2-H2(L2)-FR3-H3(L3)-FR4.
  • an “immunoconjugate” is an antibody conjugated to one or more heterologous molecule(s), including but not limited to a label or cytotoxic agent. Optionally such conjugation is via a linker.
  • a “linker” as used herein is a structure that covalently or non-covalently connects the anti-BBB-R antibody to heterologous molecule.
  • a linker is a peptide.
  • a linker is a chemical linker.
  • a “label” is a marker coupled with the antibody herein and used for detection or imaging.
  • labels include: radiolabel, a fluorophore, a chromophore, or an affinity tag.
  • the label is a radiolabel used for medical imaging, for example tc99m or I123, or a spin label for nuclear magnetic resonance (NMR) imaging (also known as magnetic resonance imaging, mri), such as iodine-123 again, iodine-131, indium-111, fluorine-19, carbon-13, nitrogen-15, oxygen-17, gadolinium, manganese, iron, etc.
  • NMR nuclear magnetic resonance
  • mammals include, but are not limited to, domesticated animals (e.g., cows, sheep, cats, dogs, and horses), primates (e.g., humans and non-human primates such as monkeys), rabbits, and rodents (e.g., mice and rats).
  • domesticated animals e.g., cows, sheep, cats, dogs, and horses
  • primates e.g., humans and non-human primates such as monkeys
  • rabbits e.g., mice and rats
  • rodents e.g., mice and rats.
  • the individual or subject is a human.
  • an “isolated” antibody is one which has been separated from a component of its natural environment.
  • an antibody is purified to greater than 95% or 99% purity as determined by, for example, electrophoretic (e.g., SDS-PAGE, isoelectric focusing (IEF), capillary electrophoresis) or chromatographic (e.g., ion exchange or reverse phase HPLC) methods.
  • electrophoretic e.g., SDS-PAGE, isoelectric focusing (IEF), capillary electrophoresis
  • chromatographic e.g., ion exchange or reverse phase HPLC
  • package insert is used to refer to instructions customarily included in commercial packages of therapeutic products, that contain information about the indications, usage, dosage, administration, combination therapy, contraindications and/or warnings concerning the use of such therapeutic products.
  • pharmaceutical formulation refers to a preparation which is in such form as to permit the biological activity of an active ingredient contained therein to be effective, and which contains no additional components which are unacceptably toxic to a subject to which the formulation would be administered.
  • a “pharmaceutically acceptable carrier” refers to an ingredient in a pharmaceutical formulation, other than an active ingredient, which is nontoxic to a subject.
  • a pharmaceutically acceptable carrier includes, but is not limited to, a buffer, excipient, stabilizer, or preservative.
  • treatment refers to clinical intervention in an attempt to alter the natural course of the individual being treated, and can be performed either for prophylaxis or during the course of clinical pathology. Desirable effects of treatment include, but are not limited to, preventing occurrence or recurrence of disease, alleviation of symptoms, diminishment of any direct or indirect pathological consequences of the disease, preventing metastasis, decreasing the rate of disease progression, amelioration or palliation of the disease state, and remission or improved prognosis.
  • antibodies of the invention are used to delay development of a disease or to slow the progression of a disease.
  • the methods and articles of manufacture of the present invention use, or incorporate, an antibody that binds to a BBB-R.
  • the BBB-R antigen to be used for production of, or screening for, antibodies may be, e.g., a soluble form of or a portion thereof (e.g. the extracellular domain) of the BBB-R containing the desired epitope.
  • cells expressing BBB-R at their cell surface can be used to generate, or screen for, antibodies.
  • Other forms and presentations of BBB-R useful for generating antibodies will be apparent to those skilled in the art.
  • BBB-Rs herein include transferrin receptor (TfR), insulin receptor, insulin-like growth factor receptor (IGF-R), low density lipoprotein receptor-related protein 1 (LRP1) and LRP8 etc, glucose transporter 1 (Glut1) and heparin-binding epidermal growth factor-like growth factor (HB-EGF).
  • TfR transferrin receptor
  • IGF-R insulin receptor
  • LRP1 low density lipoprotein receptor-related protein 1
  • Glut1 glucose transporter 1
  • HB-EGF heparin-binding epidermal growth factor-like growth factor
  • a “low affinity” anti-BBB-R (e.g. anti-TfR) antibody is selected based on the data herein demonstrating that such antibodies display improved CNS (for example, brain) uptake.
  • various assays for measuring antibody affinity are available including, without limitation: Scatchard assay and surface plasmon resonance technique (e.g. using BIACORE®).
  • the antibody has an affinity for the BBB-R antigen (e.g.
  • the affinity may be in the range from about 5 nM to about 50 ⁇ M, or in the range from about 20 nM to about 30 ⁇ M, or in the range from about 30 nM to about 30 ⁇ M, or in the range from about 50 nM to about 1 ⁇ M, or in the range from about 100 nM to about 500 nM, e.g. as measured by Scatchard analysis or BIACORE®.
  • the antibody has a dissociation half-life from the BBB-R antigen (e.g. for TfR) of less than 1 minute, less than 2 minutes, less than 3 minutes, less than four minutes, less than 5 minutes, or less than 10 minutes to about 20 minutes, or to about 30 minutes, as measured by competition binding analysis or BIACORE®.
  • a dissociation half-life from the BBB-R antigen e.g. for TfR
  • the invention provides a method of making an antibody useful for transporting a neurological disorder drug across the blood-brain barrier comprising selecting an antibody from a panel of antibodies against a blood-brain barrier receptor (BBB-R) because it has an affinity for the BBB-R which is in the range from about 5 nM, or from about 20 nM, or from about 100 nM, to about 50 ⁇ M, or to about 30 ⁇ M, or to about 10 ⁇ M, or to about 1 ⁇ M, or to about 500 mM.
  • BBB-R blood-brain barrier receptor
  • the affinity may be in the range from about 5 nM to about 50 ⁇ M, or in the range from about 20 nM to about 30 ⁇ M, or in the range from about 30 nM to about 30 ⁇ M, or in the range from about 50 nM to about 1 ⁇ M, or in the range from about 100 nM to about 500 nM, e.g. as measured by Scatchard analysis or BIACORE®.
  • a heterologous molecule/compound conjugating a heterologous molecule/compound to an antibody will often decrease the affinity of the antibody for its target due, e.g., to steric hindrance or even to elimination of one binding arm if the antibody is made multispecific with one or more arms binding to a different antigen than the antibody's original target.
  • a low affinity antibody of the invention specific for TfR conjugated to BACE1 had a Kd for TfR as measured by BIACORE of about 30 nM.
  • a low affinity antibody of the invention specific for TfR conjugated to BACE1 had a Kd for TfR as measured by BIACORE of about 600 nM.
  • a low affinity antibody of the invention specific for TfR conjugated to BACE1 had a Kd for TfR as measured by BIACORE of about 20 ⁇ M. In another embodiment, a low affinity antibody of the invention specific for TfR conjugated to BACE1 had a Kd for TfR as measured by BIACORE of about 30 ⁇ M.
  • the anti-BBB-R antibody of interest can be iodinated using the lactoperoxidase method (Bennett and Horuk, Methods in Enzymology 288 pg. 134-148 (1997)).
  • a radiolabeled anti-BBB-R antibody is purified from free 125 I-Na by gel filtration using a NAP-5 column and its specific activity measured.
  • Competition reaction mixtures of 50 ⁇ L containing a fixed concentration of iodinated antibody and decreasing concentrations of serially diluted unlabeled antibody are placed into 96-well plates.
  • Cells transiently expressing BBB-R are cultured in growth media, consisting of Dulbecco's modified eagle's medium (DMEM) (Genentech) supplemented with 10% FBS, 2 mM L-glutamine and 1 ⁇ penicillin-streptomycin at 37° C. in 5% CO 2 .
  • DMEM Dulbecco's modified eagle's medium
  • FBS fetal bovine serum albumin
  • pH 7.2 pH 7.2
  • 0.2% sodium azide binding buffer
  • the washed cells are added at an approximate density of 200,000 cells in 0.2 mL of binding buffer to the 96-well plates containing the 50- ⁇ L competition reaction mixtures.
  • the final concentration of the unlabeled antibody in the competition reaction with cells is varied, starting at 1000 nM and then decreasing by 1:2 fold dilution for 10 concentrations and including a zero-added, buffer-only sample.
  • Competition reactions with cells for each concentration of unlabeled antibody are assayed in triplicate.
  • Competition reactions with cells are incubated for 2 hours at room temperature. After the 2-hour incubation, the competition reactions are transferred to a filter plate and washed four times with binding buffer to separate free from bound iodinated antibody.
  • the filters are counted by gamma counter and the binding data are evaluated using the fitting algorithm of Munson and Rodbard (1980) to determine the binding affinity of the antibody.
  • An exemplary scatchard analysis using the compositions of the invention may be performed as follows.
  • Anti-TFR A was iodinated using the lactoperoxidase method (Bennett and Horuk, Methods in Enzymology 288 pg. 134-148 (1997)).
  • Radiolabeled anti-TFR A was purified from free 125 I-Na by gel filtration using a NAP-5 column; purified anti-TFR A had a specific activity of 19.82 ⁇ Ci/ ⁇ g.
  • Competition reaction mixtures of 50 ⁇ L containing a fixed concentration of iodinated antibody and decreasing concentrations of serially diluted unlabeled antibody were placed into 96-well plates.
  • the 293 cells transiently expressing murine TfR were cultured in growth media, consisting of Dulbecco's modified eagle's medium (DMEM) (Genentech) supplemented with 10% FBS, 2 mM L-glutamine and 1 ⁇ penicillin-streptomycin at 37° C. in 5% CO 2 .
  • DMEM Dulbecco's modified eagle's medium
  • FBS fetal bovine serum albumin
  • pH 7.2 fetal bovine serum albumin
  • 0.2% sodium azide binding buffer
  • the final concentration of the iodinated antibody in each competition reaction with cells was 100 pM (134,000 cpm per 0.25 mL).
  • the final concentration of the unlabeled antibody in the competition reaction with cells varied, starting at 1000 nM and then decreasing by 1:2 fold dilution for 10 concentrations and including a zero-added, buffer-only sample.
  • Competition reactions with cells for each concentration of unlabeled antibody were assayed in triplicate.
  • Competition reactions with cells were incubated for 2 hours at room temperature. After the 2-hour incubation, the competition reactions were transferred to a Millipore Multiscreen filter plate and washed four times with binding buffer to separate free from bound iodinated antibody.
  • the filters were counted on a Wallac Wizard 1470 gamma counter (PerkinElmer Life and Analytical Sciences; Waltham, Mass.).
  • the binding data were evaluated using New Ligand software (Genentech), which uses the fitting algorithm of Munson and Rodbard (1980) to determine the binding affinity of the antibody.
  • BIACORE® analysis using the compositions of the invention may be performed as follows. Kd was measured using surface plasmon resonance assays using a BIACORE®-2000 (BIAcore, Inc., Piscataway, N.J.) at 25° C. using anti-human Fc kit (BiAcore Inc., Piscataway, N.J.). Briefly, carboxymethylated dextran biosensor chips (CM5, BIACORE, Inc.) were activated with N-ethyl-N′-(3-dimethylaminopropyl)-carbodiimide hydrochloride (EDC) and N-hydroxysuccinimide (NHS) according to the supplier's instructions.
  • CM5 carboxymethylated dextran biosensor chips
  • EDC N-ethyl-N′-(3-dimethylaminopropyl)-carbodiimide hydrochloride
  • NHS N-hydroxysuccinimide
  • Anti-human Fc antibody was diluted with 10 mM sodium acetate, pH 4.0, to 50 ⁇ g/ml before injection at a flow rate of 5 ⁇ l/minute to achieve approximately 10000 response units (RU) of coupled protein. Following the injection of antibody, 1 M ethanolamine was injected to block unreacted groups. For kinetics measurements, monospecific or multispecific anti-TfR antibody variants were injected in HBS-P to reach about 220 RU, then two-fold serial dilutions of MuTfR-His (0.61 nM to 157 nM) were injected in HBS-P at 25° C. at a flow rate of approximately 30 ⁇ l/min.
  • Kd is measured using surface plasmon resonance assays with a BIACORE®-2000 device (BIAcore, Inc., Piscataway, N.J.) at 25° C. using anti-human Fc kit (BiAcore Inc., Piscataway, N.J.). Briefly, carboxymethylated dextran biosensor chips (CM5, BIACORE, Inc.) are activated with N-ethyl-N′-(3-dimethylaminopropyl)-carbodiimide hydrochloride (EDC) and N-hydroxysuccinimide (NHS) according to the supplier's instructions.
  • CM5 carboxymethylated dextran biosensor chips
  • EDC N-ethyl-N′-(3-dimethylaminopropyl)-carbodiimide hydrochloride
  • NHS N-hydroxysuccinimide
  • Anti-human Fc antibody is diluted with 10 mM sodium acetate, pH 4.0, to 50 ⁇ g/ml before injection at a flow rate of 5 ⁇ l/minute to achieve approximately 10000 response units (RU) of coupled protein. Following the injection of antibody, 1 M ethanolamine is injected to block unreacted groups.
  • anti-BBB-R antibody variants are injected in HBS-P to reach about 220 RU, then two-fold serial dilutions of BBB-R-His (0.61 nM to 157 nM) are injected in HBS-P at 25° C. at a flow rate of approximately 30 ⁇ l/min.
  • association rates (kon) and dissociation rates (koff) are calculated using a simple one-to-one Langmuir binding model (BIACORE® Evaluation Software version 3.2) by simultaneously fitting the association and dissociation sensorgrams.
  • the equilibrium dissociation constant (Kd) is calculated as the ratio koff/kon. See, e.g., Chen et al., J. Mol. Biol. 293:865-881 (1999).
  • a surrogate measurement for the affinity of one or more antibodies for the BBB-R is its half maximal inhibitory concentration (IC50), a measure of how much of the antibody is needed to inhibit the binding of a known BBB-R ligand to the BBB-R by 50%.
  • IC50 half maximal inhibitory concentration
  • Several methods of determining the IC50 for a given compound are art-known; a common approach is to perform a competition binding assay, such as that described herein in the examples, i.e. with regard to FIG. 1A .
  • a high IC50 indicates that more of the antibody is required to inhibit binding of the known ligand, and thus that the antibody's affinity for that ligand is relatively low.
  • a low IC50 indicates that less of the antibody is required to inhibit binding of the known ligand, and thus that the antibody's affinity for that ligand is relatively high.
  • An exemplary competitive ELISA assay to measure IC50 is one in which increasing concentrations of anti-TfR or anti-TfR/brain antigen (i.e., anti-TfR/BACE1, anti-TfR/Abeta and the like) variant antibodies are used to compete against biotinylated TfR A for binding to TfR.
  • the anti-TfR competition ELISA was performed in Maxisorp plates (Neptune, N.J.) coated with 2.5 ⁇ g/ml of purified murine TfR extracellular domain in PBS at 4° C. overnight. Plates were washed with PBS/0.05% Tween 20 and blocked using Superblock blocking buffer in PBS (Thermo Scientific, Hudson, N.H.).
  • the low affinity anti-BBB-R antibody herein is coupled with a label and/or neurological disorder drug or imaging agent in order to more efficiently transport the label and/or drug or imaging agent across the BBB.
  • a label and/or neurological disorder drug or imaging agent in order to more efficiently transport the label and/or drug or imaging agent across the BBB.
  • Such coupling can be achieved by chemical cross-linkers or by generating fusion proteins, etc.
  • Covalent conjugation can either be direct or via a linker.
  • direct conjugation is by construction of a protein fusion (i.e., by genetic fusion of the two genes encoding the BBB-R antibody and the neurological disorder drug and expression as a single protein).
  • direct conjugation is by formation of a covalent bond between a reactive group on one of the two portions of the anti-BBB-R antibody and a corresponding group or acceptor on the neurological drug.
  • direct conjugation is by modification (i.e., genetic modification) of one of the two molecules to be conjugated to include a reactive group (as nonlimiting examples, a sulfhydryl group or a carboxyl group) that forms a covalent attachment to the other molecule to be conjugated under appropriate conditions.
  • a reactive group as nonlimiting examples, a sulfhydryl group or a carboxyl group
  • a molecule i.e., an amino acid
  • a desired reactive group i.e., a cysteine residue
  • Non-covalent conjugation can be by any nonconvalent attachment means, including hydrophobic bonds, ionic bonds, electrostatic interactions, and the like, as will be readily understood by one of ordinary skill in the art. Conjugation may also be performed using a variety of linkers.
  • an anti-BBB-R antibody and a neurological drug may be conjugated using a variety of bifunctional protein coupling agents such as N-succinimidyl-3-(2-pyridyldithio) propionate (SPDP), succinimidyl-4-(N-maleimidomethyl)cyclohexane-1-carboxylate (SMCC), iminothiolane (IT), bifunctional derivatives of imidoesters (such as dimethyl adipimidate HCl), active esters (such as disuccinimidyl suberate), aldehydes (such as glutaraldehyde), bis-azido compounds (such as bis(p-azidobenzoyl) hexanediamine), bis-diazonium derivatives (such as bis-(p-diazoniumbenzoyl)-ethylenediamine), diisocyanates (such as toluene 2,6-diisocyanate), and bis-active fluorine compounds
  • Peptide linkers comprised of from one to twenty amino acids joined by peptide bonds, may also be used.
  • the amino acids are selected from the twenty naturally-occurring amino acids.
  • one or more of the amino acids are selected from glycine, alanine, proline, asparagine, glutamine and lysine.
  • the linker may be a “cleavable linker” facilitating release of the neurological drug upon delivery to the brain.
  • an acid-labile linker, peptidase-sensitive linker, photolabile linker, dimethyl linker or disulfide-containing linker (Chari et al., Cancer Res. 52:127-131 (1992); U.S. Pat. No. 5,208,020) may be used.
  • the invention herein expressly contemplates, but is not limited to, conjugates prepared with cross-linker reagents including, but not limited to, BMPS, EMCS, GMBS, HBVS, LC-SMCC, MBS, MPBH, SBAP, SIA, SLAB, SMCC, SMPB, SMPH, sulfo-EMCS, sulfo-GMBS, sulfo-KMUS, sulfo-MBS, sulfo-SIAB, sulfo-SMCC, and sulfo-SMPB, and SVSB (succinimidyl-(4-vinylsulfone)benzoate) which are commercially available (e.g., from Pierce Biotechnology, Inc., Rockford, Ill., U.S.A).
  • cross-linker reagents including, but not limited to, BMPS, EMCS, GMBS, HBVS, LC-SMCC, MBS, MPBH, SB
  • a neurological drug may be selected that is an analgesic including, but not limited to, a narcotic/opioid analgesic (i.e., morphine, fentanyl, hydrocodone, meperidine, methadone, oxymorphone, pentazocine, propoxyphene, tramadol, codeine and oxycodone), a nonsteroidal anti-inflammatory drug (NSAID) (i.e., ibuprofen, naproxen, diclofenac, diflunisal, etodolac, fenoprofen, flurbiprofen, indomethacin, ketorolac, mefenamic acid, meloxicam, nabumetone, oxaprozin, piroxicam, sulindac, and tolmetin), a corticosteroid (i.e., cortisone, prednisone, prednisolone, dexa
  • NSAID non
  • a neurological drug may be selected that is an anti-vertigo agent including, but not limited to, meclizine, diphenhydramine, promethazine and diazepam.
  • a neurological drug may be selected that is an anti-nausea agent including, but not limited to, promethazine, chlorpromazine, prochlorperazine, trimethobenzamide, and metoclopramide.
  • a neurological drug may be selected that is a growth hormone or neurotrophic factor; examples include but are not limited to brain-derived neurotrophic factor (BDNF), nerve growth factor (NGF), neurotrophin-4/5, fibroblast growth factor (FGF)-2 and other FGFs, neurotrophin (NT)-3, erythropoietin (EPO), hepatocyte growth factor (HGF), epidermal growth factor (EGF), transforming growth factor (TGF)-alpha, TGF-beta, vascular endothelial growth factor (VEGF), interleukin-1 receptor antagonist (IL-1ra), ciliary neurotrophic factor (CNTF), glial-derived neurotrophic factor (GDNF), neurturin, platelet-derived growth factor (PDGF), heregulin, neuregulin, artemin, persephin, interleukins, glial cell line derived neurotrophic factor (GFR), granulocyte-colony stimulating factor (CSF), granulocyte
  • BDNF brain-
  • a neurological drug may be selected that is a chemotherapeutic agent.
  • chemotherapeutic agents include alkylating agents such as thiotepa and CYTOXAN® cyclosphosphamide; alkyl sulfonates such as busulfan, improsulfan and piposulfan; aziridines such as benzodopa, carboquone, meturedopa, and uredopa; ethylenimines and methylamelamines including altretamine, triethylenemelamine, trietylenephosphoramide, triethiylenethiophosphor-amide and trimethylolomelamine; acetogenins (especially bullatacin and bullatacinone); delta-9-tetrahydrocannabinol (dronabinol, MARINOL®); beta-lapachone; lapachol; colchicines; betulinic acid; a camptothecin (including the synthetic analogue topot).
  • calicheamicin especially calicheamicin gamma1I and calicheamicin omegaI1 (see, e.g., Agnew, Chem Intl. Ed. Engl., 33: 183-186 (1994)); dynemicin, including dynemicin A; an esperamicin; as well as neocarzinostatin chromophore and related chromoprotein enediyne antibiotic chromophores), aclacinomysins, actinomycin, authramycin, azaserine, bleomycins, cactinomycin, carabicin, carminomycin, carzinophilin, chromomycinis, dactinomycin, daunorubicin, detorubicin, 6-diazo-5-oxo-L-norleucine, ADRIAMYCIN® doxorubicin (including morpholino-doxorubicin, cyano
  • chemotherapeutic agents are anti-hormonal agents that act to regulate, reduce, block, or inhibit the effects of hormones that can promote the growth of cancer, and are often in the form of systemic, or whole-body treatment. They may be hormones themselves.
  • anti-estrogens and selective estrogen receptor modulators include, for example, tamoxifen (including NOLVADEX® tamoxifen), EVISTA® raloxifene, droloxifene, 4-hydroxytamoxifen, trioxifene, keoxifene, LY117018, onapristone, and FARESTON® toremifene; anti-progesterones; estrogen receptor down-regulators (ERDs); agents that function to suppress or shut down the ovaries, for example, leutinizing hormone-releasing hormone (LHRH) agonists such as LUPRON® and ELIGARD® leuprolide acetate, goserelin acetate, buserelin acetate and tripterelin; other anti-androgens such as flutamide, nilutamide and bicalutamide; and aromatase inhibitors that inhibit the enzyme aromatase, which regulates estrogen production in the
  • SERMs selective
  • chemotherapeutic agents includes bisphosphonates such as clodronate (for example, BONEFOS® or OSTAC®), DIDROCAL® etidronate, NE-58095, ZOMETA® zoledronic acid/zoledronate, FOSAMAX® alendronate, AREDIA® pamidronate, SKELID® tiludronate, or ACTONEL® risedronate; as well as troxacitabine (a 1,3-dioxolane nucleoside cytosine analog); antisense oligonucleotides, particularly those that inhibit expression of genes in signaling pathways implicated in aberrant cell proliferation, such as, for example, PKC-alpha, Raf, H-Ras, and epidermal growth factor receptor (EGF-R); vaccines such as THERATOPE® vaccine and gene therapy vaccines, for example, ALLOVECTIN® vaccine, LEUVECTIN® vaccine, and VAXID® vaccine; LURTOTECAN®
  • anti-cancer immunoglobulins including, but not limited to, trastuzumab, pertuzumab, bevacizumab, alemtuxumab, cetuximab, gemtuzumab ozogamicin, ibritumomab tiuxetan, panitumumab and rituximab.
  • antibodies in conjunction with a toxic label or conjugate may be used to target and kill desired cells (i.e., cancer cells), including, but not limited to, tositumomab with a 131 I radiolabel, or trastuzumab emtansine.
  • a neurological drug may be selected that is an anti-angiogenic ophthalmic agent (i.e., bevacizumab, ranibizumab and pegaptanib), an ophthalmic glaucoma agent (i.e., carbachol, epinephrine, demecarium bromide, apraclonidine, brimonidine, brinzolamide, levobunolol, timolol, betaxolol, dorzolamide, bimatoprost, carteolol, metipranolol, dipivefrin, travoprost and latanoprost), a carbonic anhydrase inhibitor (i.e., methazolamide and acetazolamide), an ophthalmic antihistamine (i.e., naphazoline, phenylephrine and tetrahydrozoline), an ocular lubricant, an ophthalmic an anti-angiogenic o
  • a neurological drug may be selected that is an anticonvulsant or antiepileptic including, but not limited to, barbiturate anticonvulsants (i.e., primidone, metharbital, mephobarbital, allobarbital, amobarbital, aprobarbital, alphenal, barbital, brallobarbital and phenobarbital), benzodiazepine anticonvulsants (i.e., diazepam, clonazepam, and lorazepam), carbamate anticonvulsants (i.e.
  • barbiturate anticonvulsants i.e., primidone, metharbital, mephobarbital, allobarbital, amobarbital, aprobarbital, alphenal, barbital, brallobarbital and phenobarbital
  • benzodiazepine anticonvulsants i.e., diazepam, clonazepam,
  • felbamate carbonic anhydrase inhibitor anticonvulsants (i.e., acetazolamide, topiramate and zonisamide), dibenzazepine anticonvulsants (i.e., rufinamide, carbamazepine, and oxcarbazepine), fatty acid derivative anticonvulsants (i.e., divalproex and valproic acid), gamma-aminobutyric acid analogs (i.e., pregabalin, gabapentin and vigabatrin), gamma-aminobutyric acid reuptake inhibitors (i.e., tiagabine), gamma-aminobutyric acid transaminase inhibitors (i.e., vigabatrin), hydantoin anticonvulsants (i.e.
  • phenytoin, ethotoin, fosphenytoin and mephenytoin miscellaneous anticonvulsants (i.e., lacosamide and magnesium sulfate), progestins (i.e., progesterone), oxazolidinedione anticonvulsants (i.e., paramethadione and trimethadione), pyrrolidine anticonvulsants (i.e., levetiracetam), succinimide anticonvulsants (i.e., ethosuximide and methsuximide), triazine anticonvulsants (i.e., lamotrigine), and urea anticonvulsants (i.e., phenacemide and pheneturide).
  • progestins i.e., progesterone
  • oxazolidinedione anticonvulsants i.e., paramethadione and trimethadione
  • a neurological drug may be selected that is itself or otherwise mimics the activity of the enzyme that is impaired in the disease.
  • Exemplary recombinant enzymes for the treatment of lysosomal storage disorders include, but are not limited to those set forth in e.g., U.S. Patent Application publication no.
  • 2005/0142141 i.e., alpha-L-iduronidase, iduronate-2-sulphatase, N-sulfatase, alpha-N-acetylglucosaminidase, N-acetyl-galactosamine-6-sulfatase, beta-galactosidase, arylsulphatase B, beta-glucuronidase, acid alpha-glucosidase, glucocerebrosidase, alpha-galactosidase A, hexosaminidase A, acid sphingomyelinase, beta-galactocerebrosidase, beta-galactosidase, arylsulfatase A, acid ceramidase, aspartoacylase, palmitoyl-protein thioesterase 1 and tripeptidyl amino peptidase 1).
  • a neurological drug may be selected that includes, but is not limited to, an antibody or other binding molecule (including, but not limited to a small molecule, a peptide, an aptamer, or other protein binder) that specifically binds to a target selected from: beta secretase, tau, presenilin, amyloid precursor protein or portions thereof, amyloid beta peptide or oligomers or fibrils thereof, death receptor 6 (DR6), receptor for advanced glycation endproducts (RAGE), parkin, and huntingtin; a cholinesterase inhibitor (i.e., galantamine, donepezil, rivastigmine and tacrine); an NMDA receptor antagonist (i.e., memantine), a monoamine depletor (i.e., tetrabenazine); an ergoloid mesylate; an anticholinergic antiparkinsonism agent (i.e., procyclidine, diphenhydramine, trihex
  • a neurological drug may be selected that includes, but is not limited to, an antiviral compound (including, but not limited to, an adamantane antiviral (i.e., rimantadine and amantadine), an antiviral interferon (i.e., peginterferon alfa-2b), a chemokine receptor antagonist (i.e., maraviroc), an integrase strand transfer inhibitor (i.e., raltegravir), a neuraminidase inhibitor (i.e., oseltamivir and zanamivir), a non-nucleoside reverse transcriptase inhibitor (i.e., efavirenz, etravirine, delavirdine and nevirapine), a nucleoside reverse transcriptase inhibitors (tenofovir, abacavir, lamivudine, zidovudine, stavudine, ente
  • an antiviral compound including,
  • a neurological drug may be selected that includes, but is not limited to, a thrombolytic (i.e., urokinase,reteplase, reteplase and tenecteplase), a platelet aggregation inhibitor (i.e., aspirin, cilostazol, clopidogrel, prasugrel and dipyridamole), a statin (i.e., lovastatin, pravastatin, fluvastatin, rosuvastatin, atorvastatin, simvastatin, cerivastatin and pitavastatin), and a compound to improve blood flow or vascular flexibility, including, e.g., blood pressure medications.
  • a thrombolytic i.e., urokinase,reteplase, reteplase and tenecteplase
  • a platelet aggregation inhibitor i.e., aspirin, cilostazol,
  • a neurological drug may be selected from a behavior-modifying compound including, but not limited to, an atypical antipsychotic (i.e., risperidone, olanzapine, apripiprazole, quetiapine, paliperidone, asenapine, clozapine, iloperidone and ziprasidone), a phenothiazine antipsychotic (i.e., prochlorperazine, chlorpromazine, fluphenazine, perphenazine, trifluoperazine, thioridazine and mesoridazine), a thioxanthene (i.e., thiothixene), a miscellaneous antipsychotic (i.e., pimozide, lithium, molindone, haloperidol and loxapine), a selective serotonin reuptake inhibitor (i.e., citalopram, escitalopram
  • a neurological drug may be selected that addresses the inflammation itself (i.e., a nonsteroidal anti-inflammatory agent such as ibuprofen or naproxen), or one which treats the underlying cause of the inflammation (i.e., an anti-viral or anti-cancer agent).
  • a nonsteroidal anti-inflammatory agent such as ibuprofen or naproxen
  • an anti-viral or anti-cancer agent i.e., an anti-viral or anti-cancer agent
  • the “coupling” is achieved by generating a multispecific antibody (e.g. a bispecific antibody).
  • Multispecific antibodies are monoclonal antibodies that have binding specificities for at least two different antigens or epitopes.
  • the multispecific antibody comprises a first antigen binding site which binds the BBB-R and a second antigen binding site which binds a brain antigen, such as beta-secretase 1 (BACE1) or Abeta, and the other brain antigens disclosed herein.
  • BACE1 beta-secretase 1
  • An exemplary brain antigen bound by such multispecific/bispecific antibody is BACE1, and an exemplary antibody binding thereto is the YW412.8.31 antibody in FIGS. 9A-B herein.
  • the brain antigen is Abeta, exemplary such antibodies being described in WO2007068412, WO2008011348, WO20080156622, and WO2008156621, expressly incorporated herein by reference, with an exemplary Abeta antibody comprising the IgG4 MABT5102A antibody comprising the heavy and light chain amino acid sequences in FIGS. 11A and 11B , respectively.
  • Multispecific antibodies include, but are not limited to, recombinant co-expression of two immunoglobulin heavy chain-light chain pairs having different specificities (see Milstein and Cuello, Nature 305: 537 (1983)), WO 93/08829, and Traunecker et al., EMBO J. 10: 3655 (1991)), and “knob-in-hole” engineering (see, e.g., U.S. Pat. No. 5,731,168). Multi-specific antibodies may also be made by engineering electrostatic steering effects for making antibody Fc-heterodimeric molecules (WO 2009/089004A1); cross-linking two or more antibodies or fragments (see, e.g., U.S. Pat. No.
  • the antibody or fragment herein also includes a “Dual Acting FAb” or “DAF” comprising an antigen binding site that binds to the BBB-R (e.g. TfR) as well as the brain antigen (e.g. BACE1) (see, US 2008/0069820, for example).
  • DAF Double Acting FAb
  • BBB-R e.g. TfR
  • BACE1 brain antigen
  • the antibody is an antibody fragment, various such fragments being disclosed above.
  • the antibody is an intact or full-length antibody.
  • intact antibodies can be assigned to different classes. There are five major classes of intact antibodies: IgA, IgD, IgE, IgG, and IgM, and several of these may be further divided into subclasses (isotypes), e.g., IgG1, IgG2, IgG3, IgG4, IgA, and IgA2.
  • the heavy chain constant domains that correspond to the different classes of antibodies are called ⁇ , ⁇ , ⁇ , ⁇ , and ⁇ , respectively.
  • the subunit structures and three-dimensional configurations of different classes of immunoglobulins are well known.
  • the intact antibody lacks effector function.
  • the inact antibody has reduced effector function.
  • the antibody is a chimeric, humanized, or human antibody or antigen-binding fragment thereof.
  • ELISA enzyme linked immunosorbent assay
  • an antibody of the invention is tested for its antigen binding activity, e.g., by known methods such as ELISA, Western blot, etc.
  • Assays for evaluating uptake of systemically administered antibody and other biological activity of the antibody can be performed as disclosed in the examples or as known for the anti-CNS antigen antibody of interest.
  • Competition assays may be used to identify an antibody that competes with any of the anti-BACE1 antibodies or Fabs descried herein, for example, YW412.8, YW412.8.31, YW412.8.30, YW412.8.2, YW412.8.29, YW412.8.51, Fab12, LC6, LC9, LC10 for binding to BACE1.
  • such a competing antibody binds to the same epitope (e.g., a linear or a conformational epitope) that is bound by any of the anti-BACE1 antibodies or Fabs descried herein, for example, YW412.8, YW412.8.31, YW412.8.30, YW412.8.2, YW412.8.29, YW412.8.51, Fab12, LC6, LC9, LC10.
  • Detailed exemplary methods for mapping an epitope to which an antibody binds are provided in Morris (1996) “Epitope Mapping Protocols,” in Methods in Molecular Biology vol. 66 (Humana Press, Totowa, N.J.).
  • immobilized BACE1 is incubated in a solution comprising a first labeled antibody that binds to BACE1 (e.g., YW412.8, YW412.8.31, YW412.8.30, YW412.8.2, YW412.8.29, YW412.8.51, Fab12, LC6, LC9, LC10) and a second unlabeled antibody that is being tested for its ability to compete with the first antibody for binding to BACE1.
  • the second antibody may be present in a hybridoma supernatant.
  • immobilized BACE1 is incubated in a solution comprising the first labeled antibody but not the second unlabeled antibody.
  • assays are provided for identifying anti-BACE1 antibodies thereof having biological activity.
  • Biological activity may include, e.g., inhibition of BACE1 aspartyl protease activity.
  • Antibodies having such biological activity in vivo and/or in vitro are also provided, e.g. as evaluated by homogeneous time-resolved fluorescence HTRF assay or a microfluidic capillary electrophoretic (MCE) assay using synthetic substrate peptides, or in vivo in cell lines which express BACE1 substrates such as APP.
  • MCE microfluidic capillary electrophoretic
  • the antibody (including the multispecific antibody) herein is optionally recombinantly produced in a host cell transformed with nucleic acid sequences encoding its heavy and/or light chains (e.g. where the host cell or host cells have been transformed by one or more vectors with the nucleic acid therein).
  • the host cell(s) is optionally a mammalian cell, for example a Chinese Hamster Ovary (CHO) cell.
  • Therapeutic formulations of the antibodies used in accordance with the present invention are prepared for storage by mixing an antibody having the desired degree of purity with optional pharmaceutically acceptable carriers, excipients or stabilizers ( Remington's Pharmaceutical Sciences 16th edition, Osol, A. Ed. (1980)), in the form of lyophilized formulations or aqueous solutions.
  • Acceptable carriers, excipients, or stabilizers are nontoxic to recipients at the dosages and concentrations employed, and include buffers such as phosphate, citrate, and other organic acids; antioxidants including ascorbic acid and methionine; preservatives (such as octadecyldimethylbenzyl ammonium chloride; hexamethonium chloride; benzalkonium chloride, benzethonium chloride; phenol, butyl or benzyl alcohol; alkyl parabens such as methyl or propyl paraben; catechol; resorcinol; cyclohexanol; 3-pentanol; and m-cresol); low molecular weight (less than about 10 residues) polypeptides; proteins, such as serum albumin, gelatin, or immunoglobulins; hydrophilic polymers such as polyvinylpyrrolidone; amino acids such as glycine, glutamine, asparagine, histidine,
  • the formulation herein may also contain more than one active compound as necessary, optionally those with complementary activities that do not adversely affect each other.
  • the type and effective amounts of such medicaments depend, for example, on the amount of antibody present in the formulation, and clinical parameters of the subjects. Exemplary such medicaments are discussed below.
  • the active ingredients may also be entrapped in microcapsules prepared, for example, by coacervation techniques or by interfacial polymerization, for example, hydroxymethylcellulose or gelatin-microcapsules and poly-(methylmethacylate) microcapsules, respectively, in colloidal drug delivery systems (for example, liposomes, albumin microspheres, microemulsions, nano-particles and nanocapsules) or in macroemulsions.
  • colloidal drug delivery systems for example, liposomes, albumin microspheres, microemulsions, nano-particles and nanocapsules
  • One or more therapeutic agents may be encapsulated in liposomes that are coupled to anti-BBB-R (see e.g., U.S. Patent Application Publication No. 20020025313).
  • Sustained-release preparations may be prepared. Suitable examples of sustained-release preparations include semi-permeable matrices of solid hydrophobic polymers containing the antibody, which matrices are in the form of shaped articles, e.g. films, or microcapsules. Examples of sustained-release matrices include polyesters, hydrogels (for example, poly(2-hydroxyethyl-methacrylate), or poly(vinylalcohol)), polylactides (U.S. Pat. No.
  • copolymers of L-glutamic acid and ⁇ ethyl-L-glutamate copolymers of L-glutamic acid and ⁇ ethyl-L-glutamate, non-degradable ethylene-vinyl acetate, degradable lactic acid-glycolic acid copolymers such as the LUPRON DEPOTTM (injectable microspheres composed of lactic acid-glycolic acid copolymer and leuprolide acetate), and poly-D-( ⁇ )-3-hydroxybutyric acid.
  • LUPRON DEPOTTM injectable microspheres composed of lactic acid-glycolic acid copolymer and leuprolide acetate
  • poly-D-( ⁇ )-3-hydroxybutyric acid poly-D-( ⁇ )-3-hydroxybutyric acid.
  • the formulations to be used for in vivo administration must be sterile. This is readily accomplished by filtration through sterile filtration membranes.
  • the formulation is isotonic.
  • the anti-BBB-R antibodies (including multispecific antibodies comprising them) of the invention may be utilized in a variety of in vivo methods.
  • the invention provides a method of transporting a therapeutic compound across the blood-brain barrier with reduced or eliminated impact on red blood cell populations comprising exposing the anti-BBB-R antibody coupled to a therapeutic compound (e.g. a multispecific antibody which binds both the BBB-R and a brain antigen) to the BBB such that the antibody transports the therapeutic compound coupled thereto across the BBB.
  • a therapeutic compound e.g. a multispecific antibody which binds both the BBB-R and a brain antigen
  • the invention provides a method of transporting a neurological disorder drug across the blood-brain barrier comprising exposing an anti-BBB-R antibody of the invention coupled to a brain disorder drug (e.g.
  • the BBB here is in a mammal (e.g. a human), e.g. one which has a neurological disorder, including, without limitation: Alzheimer's disease (AD), stroke, dementia, muscular dystrophy (MD), multiple sclerosis (MS), amyotrophic lateral sclerosis (ALS), cystic fibrosis, Angelman's syndrome, Liddle syndrome, Parkinson's disease, Pick's disease, Paget's disease, cancer, traumatic brain injury, etc.
  • a mammal e.g. a human
  • a neurological disorder including, without limitation: Alzheimer's disease (AD), stroke, dementia, muscular dystrophy (MD), multiple sclerosis (MS), amyotrophic lateral sclerosis (ALS), cystic fibrosis, Angelman's syndrome, Liddle syndrome, Parkinson's disease, Pick's disease, Paget's disease, cancer, traumatic brain injury, etc.
  • neurological disorder is selected from: a neuropathy, an amyloidosis, cancer (e.g. involving the CNS or brain), an ocular disease or disorder, a viral or microbial infection, inflammation (e.g. of the CNS or brain), ischemia, neurodegenerative disease, seizure, behavioral disorder, lysosomal storage disease, etc.
  • Neuropathy disorders are diseases or abnormalities of the nervous system characterized by inappropriate or uncontrolled nerve signaling or lack thereof, and include, but are not limited to, chronic pain (including nociceptive pain), pain caused by an injury to body tissues, including cancer-related pain, neuropathic pain (pain caused by abnormalities in the nerves, spinal cord, or brain), and psychogenic pain (entirely or mostly related to a psychological disorder), headache, migraine, neuropathy, and symptoms and syndromes often accompanying such neuropathy disorders such as vertigo or nausea.
  • chronic pain including nociceptive pain
  • pain caused by an injury to body tissues including cancer-related pain
  • neuropathic pain pain caused by abnormalities in the nerves, spinal cord, or brain
  • psychogenic pain include, but are not limited to, headache, migraine, neuropathy, and symptoms and syndromes often accompanying such neuropathy disorders such as vertigo or nausea.
  • Amyloidoses are a group of diseases and disorders associated with extracellular proteinaceous deposits in the CNS, including, but not limited to, secondary amyloidosis, age-related amyloidosis, Alzheimer's Disease (AD), mild cognitive impairment (MCI), Lewy body dementia, Down's syndrome, hereditary cerebral hemorrhage with amyloidosis (Dutch type); the Guam Parkinson-Dementia complex, cerebral amyloid angiopathy, Huntington's disease, progressive supranuclear palsy, multiple sclerosis; Creutzfeld Jacob disease, Parkinson's disease, transmissible spongiform encephalopathy, HIV-related dementia, amyotropic lateral sclerosis (ALS), inclusion-body myositis (IBM), and ocular diseases relating to beta-amyloid deposition (i.e., macular degeneration, drusen-related optic neuropathy, and cataract).
  • AD Alzheimer's Disease
  • MCI mild cognitive impairment
  • Lewy body dementia Down's
  • Cancers of the CNS are characterized by aberrant proliferation of one or more CNS cell (i.e., a neural cell) and include, but are not limited to, glioma, glioblastoma multiforme, meningioma, astrocytoma, acoustic neuroma, chondroma, oligodendroglioma, medulloblastomas, ganglioglioma, Schwannoma, neurofibroma, neuroblastoma, and extradural, intramedullary or intradural tumors.
  • glioma glioblastoma multiforme
  • meningioma astrocytoma
  • acoustic neuroma chondroma
  • oligodendroglioma oligodendroglioma
  • medulloblastomas ganglioglioma
  • Schwannoma neurofibroma
  • neurofibroma neuroblastoma
  • Ocular diseases or disorders are diseases or disorders of the eye, which for the purposes herein is considered a CNS organ segregated by the BBB.
  • Ocular diseases or disorders include, but are not limited to, disorders of sclera, cornea, iris and ciliary body (i.e., scleritis, keratitis, corneal ulcer, corneal abrasion, snow blindness, arc eye, Thygeson's superficial punctate keratopathy, corneal neovascularisation, Fuchs' dystrophy, keratoconus, keratoconjunctivitis sicca, ulceris and uveitis), disorders of the lens (i.e., cataract), disorders of choroid and retina (i.e., retinal detachment, retinoschisis, hypertensive retinopathy, diabetic retinopathy, retinopathy, retinopathy of prematurity, age-related macular degeneration, macular degeneration (wet or dry), epiret
  • Viral or microbial infections of the CNS include, but are not limited to, infections by viruses (i.e., influenza, HIV, poliovirus, rubella,), bacteria (i.e., Neisseria sp., Streptococcus sp., Pseudomonas sp., Proteus sp., E. coli, S.
  • viruses i.e., influenza, HIV, poliovirus, rubella
  • bacteria i.e., Neisseria sp., Streptococcus sp., Pseudomonas sp., Proteus sp., E. coli, S.
  • aureus Pneumococcus sp., Meningococcus sp., Haemophilus sp., and Mycobacterium tuberculosis
  • fungi i.e., yeast, Cryptococcus neoformans
  • parasites i.e., toxoplasma gondii
  • amoebas resulting in CNS pathophysiologies including, but not limited to, meningitis, encephalitis, myelitis, vasculitis and abscess, which can be acute or chronic.
  • Inflammation of the CNS includes, but is not limited to, inflammation that is caused by an injury to the CNS, which can be a physical injury (i.e., due to accident, surgery, brain trauma, spinal cord injury, concussion) and an injury due to or related to one or more other diseases or disorders of the CNS (i.e., abscess, cancer, viral or microbial infection).
  • an injury to the CNS which can be a physical injury (i.e., due to accident, surgery, brain trauma, spinal cord injury, concussion) and an injury due to or related to one or more other diseases or disorders of the CNS (i.e., abscess, cancer, viral or microbial infection).
  • Ischemia of the CNS refers to a group of disorders relating to aberrant blood flow or vascular behavior in the brain or the causes therefor, and includes, but is not limited to: focal brain ischemia, global brain ischemia, stroke (i.e., subarachnoid hemorrhage and intracerebral hemorrhage), and aneurysm.
  • Neurodegenerative diseases are a group of diseases and disorders associated with neural cell loss of function or death in the CNS, and include, but are not limited to: adrenoleukodystrophy, Alexander's disease, Alper's disease, amyotrophic lateral sclerosis, ataxia telangiectasia, Batten disease, cockayne syndrome, corticobasal degeneration, degeneration caused by or associated with an amyloidosis, Friedreich's ataxia, frontotemporal lobar degeneration, Kennedy's disease, multiple system atrophy, multiple sclerosis, primary lateral sclerosis, progressive supranuclear palsy, spinal muscular atrophy, transverse myelitis, Refsum's disease, and spinocerebellar ataxia.
  • Seizure diseases and disorders of the CNS involve inappropriate and/or abnormal electrical conduction in the CNS, and include, but are not limited to epilepsy (i.e., absence seizures, atonic seizures, benign Rolandic epilepsy, childhood absence, clonic seizures, complex partial seizures, frontal lobe epilepsy, febrile seizures, infantile spasms, juvenile myoclonic epilepsy, juvenile absence epilepsy, Lennox-Gastaut syndrome, Landau-Kleffner Syndrome, Dravet's syndrome, Otahara syndrome, West syndrome, myoclonic seizures, mitochondrial disorders, progressive myoclonic epilepsies, psychogenic seizures, reflex epilepsy, Rasmussen's Syndrome, simple partial seizures, secondarily generalized seizures, temporal lobe epilepsy, toniclonic seizures, tonic seizures, psychomotor seizures, limbic epilepsy, partial-onset seizures, generalized-onset seizures, status epilepticus, abdominal epilepsy, akinetic seizures, autonomic seizures, massive bilateral myo
  • Behavioral disorders are disorders of the CNS characterized by aberrant behavior on the part of the afflicted subject and include, but are not limited to: sleep disorders (i.e., insomnia, parasomnias, night terrors, circadian rhythm sleep disorders, and narcolepsy), mood disorders (i.e., depression, suicidal depression, anxiety, chronic affective disorders, phobias, panic attacks, obsessive-compulsive disorder, attention deficit hyperactivity disorder (ADHD), attention deficit disorder (ADD), chronic fatigue syndrome, agoraphobia, post-traumatic stress disorder, bipolar disorder), eating disorders (i.e., anorexia or bulimia), psychoses, developmental behavioral disorders (i.e., autism, Rett's syndrome, Aspberger's syndrome), personality disorders and psychotic disorders (i.e., schizophrenia, delusional disorder, and the like).
  • sleep disorders i.e., insomnia, parasomnias, night terrors, circadian rhythm sleep disorders, and narcolepsy
  • mood disorders i
  • Lysosomal storage disorders are metabolic disorders which are in some cases associated with the CNS or have CNS-specific symptoms; such disorders include, but are not limited to: Tay-Sachs disease, Gaucher's disease, Fabry disease, mucopolysaccharidosis (types I, II, III, IV, V, VI and VII), glycogen storage disease, GM1-gangliosidosis, metachromatic leukodystrophy, Farber's disease, Canavan's leukodystrophy, and neuronal ceroid lipofuscinoses types 1 and 2, Niemann-Pick disease, Pompe disease, and Krabbe's disease.
  • diseases related to or caused by inappropriate overproduction of red blood cells, or wherein the overproduction of red blood cells is an effect of the disease can be prevented or treated by the reticulocyte-depleting effect recognized herein of anti-TfR antibodies retaining at least partial effector function.
  • the reticulocyte-depleting effect recognized herein of anti-TfR antibodies retaining at least partial effector function.
  • elevated red blood cell counts due to hyperproliferation of, e.g., reticulocytes results in thickening of blood and concomitant physiological symptoms (d'Onofrio et al., Clin. Lab. Haematol. (1996) Suppl. 1: 29-34).
  • an anti-TfR antibody of the invention wherein at least with at least partial effector function of the antibody was preserved would permit selective removal of immature reticulocyte populations without impacting normal transferrin transport into the CNS. Dosing of such an antibody could be modulated such that acute clinical symptoms could be minimized (ie, by dosing at a very low dose or at widely-spaced intervals), as well-understood in the art.
  • an antibody of the invention is used to detect a neurological disorder before the onset of symptoms and/or to assess the severity or duration of the disease or disorder.
  • the antibody permits detection and/or imaging of the neurological disorder, including imaging by radiography, tomography, or magnetic resonance imaging (MRI).
  • a low affinity anti-BBB-R antibody of the invention for use as a medicament is provided.
  • a low affinity anti-BBB-R antibody for use in treating a neurological disease or disorder e.g., Alzheimer's disease
  • red blood cells ie, reticulocytes
  • a modified low affinity anti-BBB-R antibody for use in a method of treatment as described herein is provided.
  • the invention provides a low affinity anti-BBB-R antibody modified to improve its safety for use in a method of treating an individual having a neurological disease or disorder comprising administering to the individual an effective amount of the anti-BBB-R antibody (optionally coupled to a neurological disorder drug).
  • the method further comprises administering to the individual an effective amount of at least one additional therapeutic agent.
  • the invention provides an anti-BBB-R antibody modified to improve its safety for use in reducing or inhibiting amlyoid plaque formation in a patient at risk or suffering from a neurological disease or disorder (e.g., Alzheimer's disease).
  • a neurological disease or disorder e.g., Alzheimer's disease
  • An “individual” according to any of the above embodiments is optionally a human.
  • the anti-BBB-R antibody of the invention for use in the methods of the invention improves uptake of the neurological disorder drug with which it is coupled.
  • the invention provides for the use of a low affinity anti-BBB-R antibody of the invention in the manufacture or preparation of a medicament.
  • the medicament is for treatment of neurological disease or disorder.
  • the medicament is for use in a method of treating neurological disease or disorder comprising administering to an individual having neurological disease or disorder an effective amount of the medicament. In one such embodiment, the method further comprises administering to the individual an effective amount of at least one additional therapeutic agent.
  • the invention provides a method for treating Alzheimer's disease.
  • the method comprises administering to an individual having Alzheimer's disease an effective amount of a multispecific antibody of the invention which binds both BACE1 and TfR or both Abeta and TfR.
  • the method further comprises administering to the individual an effective amount of at least one additional therapeutic agent.
  • An “individual” according to any of the above embodiments may be a human.
  • the anti-BBB-R antibodies of the invention can be used either alone or in combination with other agents in a therapy.
  • the anti-BBB-R antibody of the invention may be co-administered with at least one additional therapeutic agent.
  • an additional therapeutic agent is a therapeutic agent effective to treat the same or a different neurological disorder as the anti-BBB-R antibody is being employed to treat.
  • Exemplary additional therapeutic agents include, but are not limited to: the various neurological drugs described above, cholinesterase inhibitors (such as donepezil, galantamine, rovastigmine, and tacrine), NMDA receptor antagonists (such as memantine), amyloid beta peptide aggregation inhibitors, antioxidants, ⁇ -secretase modulators, nerve growth factor (NGF) mimics or NGF gene therapy, PPAR ⁇ agonists, HMS-CoA reductase inhibitors (statins), ampakines, calcium channel blockers, GABA receptor antagonists, glycogen synthase kinase inhibitors, intravenous immunoglobulin, muscarinic receptor agonists, nicrotinic receptor modulators, active or passive amyloid beta peptide immunization, phosphodiesterase inhibitors, serotonin receptor antagonists and anti-amyloid beta peptide antibodies.
  • the at least one additional therapeutic agent is selected for its ability to mitigate one or more side effects of the neurological drugs described
  • certain anti-BBB-R antibodies may have side effects that negatively impact reticulocyte populations in a subject treated with the anti-BBB-R antibody.
  • at least one further therapeutic agent selected for its ability to mitigate such negative side effect on reticulocyte populations is coadministered with an anti-BBB-R antibody of the invention.
  • agents to increase red blood cell (ie, reticulocyte) populations agents to support growth and development of red blood cells (ie, reticulocytes), and agents to protect red blood cell populations from the effects of the anti-BBB-R antibody
  • agents to protect red blood cell populations from the effects of the anti-BBB-R antibody include, but are not limited to, erythropoietin (EPO), iron supplements, vitamin C, folic acid, and vitamin B12, as well as physical replacement of red blood cells (ie, reticulocytes) by, for example, transfusion with similar cells, which may be from another individual of similar blood type or may have been previously extracted from the subject to whom the anti-BBB-R antibody is administered.
  • EPO erythropoietin
  • iron supplements iron supplements
  • vitamin C folic acid
  • vitamin B12 vitamin B12
  • agents intended to protect existing red blood cells are preferably administered to the subject preceding or concurrent with the anti-BBB-R antibody therapy, while agents intended to support or initiate the regrowth/development of red blood cells or blood cell populations (ie, reticulocytes or reticulocyte populations) are preferably administered concurrent with or after the anti-BBB-R antibody therapy such that such blood cells can be replenished after the anti-BBB-R antibody treatment.
  • the at least one further therapeutic agent is selected for its ability to inhibit or prevent the activation of the complement pathway upon administration of the anti-BBB-R antibody.
  • therapeutic agents include, but are not limited to, agents that interfere with the ability of the anti-BBB-R antibody to bind to or activate the complement pathway and agents that inhibit one or more molecular interactions within the complement pathway, and are described generally in Mollnes and Kirschfink (2006) Molec. Immunol. 43:107-121, the contents of which are expressly incorporated herein by reference.
  • Such combination therapies noted above encompass combined administration (where two or more therapeutic agents are included in the same or separate formulations), and separate administration, in which case, administration of the antibody of the invention can occur prior to, simultaneously, and/or following, administration of the additional therapeutic agent and/or adjuvant.
  • Antibodies of the invention can also be used in combination with other interventional therapies such as, but not limited to, radiation therapy, behavioral therapy, or other therapies known in the art and appropriate for the neurological disorder to be treated or prevented.
  • the anti-BBB-R antibody of the invention can be administered by any suitable means, including parenteral, intrapulmonary, and intranasal, and, if desired for local treatment, intralesional administration.
  • Parenteral infusions include intramuscular, intravenous, intraarterial, intraperitoneal, or subcutaneous administration. Dosing can be by any suitable route, e.g. by injections, such as intravenous or subcutaneous injections, depending in part on whether the administration is brief or chronic.
  • Various dosing schedules including but not limited to single or multiple administrations over various time-points, bolus administration, and pulse infusion are contemplated herein.
  • Antibodies of the invention are formulated, dosed, and administered in a fashion consistent with good medical practice. Factors for consideration in this context include the particular disorder being treated, the particular mammal being treated, the clinical condition of the individual patient, the cause of the disorder, the site of delivery of the agent, the method of administration, the scheduling of administration, and other factors known to medical practitioners.
  • the antibody need not be, but is optionally formulated with one or more agents currently used to prevent or treat the disorder in question or to prevent, mitigate or ameliorate one or more side effects of antibody administration.
  • the effective amount of such other agents depends on the amount of antibody present in the formulation, the type of disorder or treatment, and other factors discussed above. These are generally used in the same dosages and with administration routes as described herein, or about from 1 to 99% of the dosages described herein, or in any dosage and by any route that is empirically/clinically determined to be appropriate.
  • an antibody of the invention when used alone or in combination with one or more other additional therapeutic agents, will depend on the type of disease to be treated, the type of antibody, the severity and course of the disease, whether the antibody is administered for preventive or therapeutic purposes, previous therapy, the patient's clinical history and response to the antibody, and the discretion of the attending physician.
  • the antibody is suitably administered to the patient at one time or over a series of treatments.
  • about 1 ⁇ g/kg to 15 mg/kg (e.g. 0.1 mg/kg-10 mg/kg) of antibody can be an initial candidate dosage for administration to the patient, whether, for example, by one or more separate administrations, or by continuous infusion.
  • One typical daily dosage might range from about 1 ⁇ g/kg to 100 mg/kg or more, depending on the factors mentioned above. For repeated administrations over several days or longer, depending on the condition, the treatment would generally be sustained until a desired suppression of disease symptoms occurs.
  • One exemplary dosage of the antibody would be in the range from about 0.05 mg/kg to about 10 mg/kg.
  • one or more doses of about 0.5 mg/kg, 2.0 mg/kg, 4.0 mg/kg or 10 mg/kg (or any combination thereof) may be administered to the patient.
  • Such doses may be administered intermittently, e.g. every week or every three weeks (e.g. such that the patient receives from about two to about twenty, or e.g. about six doses of the antibody).
  • An initial higher loading dose, followed by one or more lower doses may be administered.
  • other dosage regimens may be useful.
  • one method to reduce impact on reticulocyte populations by administration of anti-TfR antibodies is to modify the amount or timing of the doses such that overall lower quantities of circulating antibody are present in the bloodstream to interact with reticulocytes.
  • a lower dose of the anti-TfR antibodies may be administered with greater frequency than a higher dose would be.
  • the dosage used may be balanced between the amount of antibody necessary to be delivered to the CNS (itself related to the affinity of the CNS antigen-specific portion of the antibody), the affinity of that antibody for TfR, and whether or not red blood cell (ie, reticulocyte)-protecting, growth and development-stimulating, or complement pathway-inhibiting compound(s) are being co- or serially administered with the antibody.
  • red blood cell ie, reticulocyte
  • an article of manufacture containing materials useful for the treatment, prevention and/or diagnosis of the disorders described above comprises a container and a label or package insert on or associated with the container.
  • Suitable containers include, for example, bottles, vials, syringes, IV solution bags, etc.
  • the containers may be formed from a variety of materials such as glass or plastic.
  • the container holds a composition which is by itself or combined with another composition effective for treating, preventing and/or diagnosing the condition and may have a sterile access port (for example the container may be an intravenous solution bag or a vial having a stopper pierceable by a hypodermic injection needle).
  • At least one active agent in the composition is an antibody of the invention.
  • the label or package insert indicates that the composition is used for treating the condition of choice.
  • the article of manufacture may comprise (a) a first container with a composition contained therein, wherein the composition comprises an antibody of the invention; and (b) a second container with a composition contained therein, wherein the composition comprises a further cytotoxic or otherwise therapeutic agent.
  • the article of manufacture in this embodiment of the invention may further comprise a package insert indicating that the compositions can be used to treat a particular condition.
  • the article of manufacture may further comprise a second (or third) container comprising a pharmaceutically-acceptable buffer, such as bacteriostatic water for injection (BWFI), phosphate-buffered saline, Ringer's solution and dextrose solution. It may further include other materials desirable from a commercial and user standpoint, including other buffers, diluents, filters, needles, and syringes.
  • BWFI bacteriostatic water for injection
  • phosphate-buffered saline such as bac
  • any of the above articles of manufacture may include an immunoconjugate of the invention in place of or in addition to an anti-BBB-R antibody.
  • the article of manufacture optionally further comprises a package insert with instructions for treating a neurological disorder in a subject, wherein the instructions indicate that treatment with the antibody as disclosed herein treats the neurological disorder, and optionally indicates that the antibody has improved uptake across the BBB due to its low affinity for the BBB-R.
  • TfR transferrin receptor
  • BBB blood-brain barrier
  • a panel of anti-TfR antibodies was generated with progressively lessening affinities for murine TfR, three of which (designated anti-TfR A , anti-TfR D , and anti-TfR E ) were further modified into a bispecific format with the other antibody arm being specific for BACE1.
  • Each monospecific and bispecific antibody was assessed in a competition ELISA assay for its affinity for murine TfR. Briefly, the assay was performed in maxisorp plates (Neptune, N. J) coated with 2.5 ⁇ g/ml of purified muTfR tagged with a hexahistidine tag (muTfR-His) in PBS at 4° C. overnight.
  • mice Antibody distribution post a single administration in mice was performed as follows. Wild type female C57B/6 mice ages 6-8 weeks were used for all studies. The animals' care was in accordance with institutional guidelines. Mice were intravenously injected with 50 mg/kg of either a control IgG, anti-BACE1 or an anti-TfR/BACE1 variant. Total injection volume did not exceed 250 uL and antibodies were diluted in D-PBS when necessary (Invitrogen). After the indicated time, mice were perfused with D-PBS at a rate of 2 mL/min for 8 minutes.
  • Anti-TfR D /BACE1 persisted longer in the brain than anti-TfR A /BACE1, with a more gradual decline in brain concentrations; however, by day 10 the concentration matched that of the control.
  • Anti-TfR E /BACE1 had a much more moderate entry into the brain (2-3-fold control), but the decline over subsequent days was much less than that of the other two antibody variants. Plasma levels of all three antibody variants ( FIG. 1B ) declined over time.
  • Anti-TfR A /BACE1 was completely cleared from the plasma by day 4, while anti-TfR D /BACE1 was fully cleared by day 10, and anti-TfR E /BACE1 still persisted in the plasma at a level comparable to that of the control IgG or anti-BACE1.
  • the presence and persistence of the transported molecule in the brain and plasma is only one measure of potential efficacy; of further interest is the activity of the molecule in those compartments. Accordingly, the BACE1 enzyme activity was assessed in both compartments by measuring the amount of A ⁇ 1-40 (a cleavage byproduct of BACE1 enzymatic activity on amyloid precursor protein (APP)). Briefly, antibody treatment and perfusions were performed in wild type mice as stated above.
  • a ⁇ 1-40 a cleavage byproduct of BACE1 enzymatic activity on amyloid precursor protein (APP)
  • hemi-brains were homogenized in 5M guanidine hydrochloride buffer and samples rotated for 3 hours at room temperature prior to diluting (1:10) in 0.25% casein, 5 mM EDTA (pH 8.0) in PBS containing freshly added aprotinin (20 mg/mL) and leupeptin (10 mg/mL). Diluted homogenates were spun at 14,000 rpm for 20 min. and supernatants were isolated for A ⁇ 1-40 measurement. Plasma was prepared as described above. The concentrations of total mouse A ⁇ 1-40 in plasma and brain were determined using a sandwich ELISA following similar procedures described above.
  • Hemi-brains for A ⁇ 1-40 measurement were homogenized in 1% NP-40 (Cal-Biochem) and rotated for 1 hour at room temperature prior to spinning at 14,000 rpm for 20 minutes.
  • Rabbit polyclonal antibody specific for the C-terminus of A ⁇ 1-40 (Millipore, Bedford, Mass.) was coated onto plates, and biotinylated anti-mouse A ⁇ monoclonal antibody M3.2 (Covance, Dedham, Mass.) was used for detection.
  • the assay had LLOQ values of 1.96 pg/ml in plasma and 39.1 pg/g in brain.
  • Statistical analysis of differences between experimental groups was performed using a two-tailed unpaired t-test.
  • FIGS. 1C and 1E The results for plasma and brain are shown in FIGS. 1C and 1E , respectively, and are consistent with the amount of antibody present in each compartment at the indicated time (see FIGS. 1B and 1D ). Importantly, the amount of A ⁇ 1-40 observed in the brain over time was lowest over the longest period in the mice treated with anti-TfR D /BACE1.
  • mice upon treatment of mice with monospecific anti-TfR A or anti-TfR D at all dose levels of 1 mg/kg or higher, unusual and acute clinical signs were observed that were not observed in mice treated with bispecific anti-TfR A /BACE1 or anti-TfR D /BACE1 (see Table 3).
  • mice All such observed effects vanished within hours after the treatment.
  • Certain monospecific antibody-treated mice also appeared to present with occasional presence of blood in the urine, as well as apparent hypotension at 1 hour post-dose based on difficult with terminal cardiac blood collection compared to collection in bispecific-treated animals.
  • mouse immature red blood cells are known to express TfR (see FIG. 2A ), to exist in the peripheral bloodstream, and the observed effects in mice may be explained if such blood cells were injured, the impact of the antibody treatment on immature red blood cells (reticulocytes) was investigated in mice.
  • mice were dosed intravenously with a single 1 mg/kg, 5 mg/kg, or 50 mg/kg anti-TfR D or anti-TfR D /BACE1 injection, or with a single 50 mg/kg control IgG injection using the same procedure as described in Example 1, and whole blood samples were taken at 1 hour post-dose and placed into potassium-EDTA-containing collection tubes. Red cell and reticulocyte counts and indices were determined on these blood samples using the Sysmex XT2000iV (Sysmex, Kobe, Japan) according to the manufacturer's instructions.
  • the Sysmex detects and classifies total reticulocytes as well as the immature reticulocyte fraction (sum of high and middle/intermediate fluorescent reticulocytes) by flow cytometry using a fluorescent polymethine dye to bind cellular RNA and measure the resulting cell light scatter characteristics.
  • anti-TfR D reduced immature reticulocyte levels at all dose levels tested, to approximately the same extent regardless of dose.
  • Treated mice in each anti-TfR D dosage group also showed acute clinical signs of similar severity and penetrance (see FIG. 2B ).
  • blood samples from the 1 mg/kg and 5 mg/kg anti-TfR D /BACE1-treated mice had similar fractions of immature reticulocytes as those from the control-IgG-treated samples.
  • the 50 mg/kg anti-TfR D /BACE1-treated mice showed a marked reduction in reticulocytes (to about 50% of control amounts) ( FIG. 2B ), but this reduction was not accompanied by any acute clinical signs.
  • the bispecific anti-TfR D -containing antibody had a lesser impact on reticulocyte levels than monospecific anti-TfR D , and did not elicit acute adverse clinical signs.
  • mice were dosed intravenously with a single 5 mg/kg, 25 mg/kg or 50 mg/kg anti-TfR A /BACE1 or anti-TfR D /BACE1 injection, or with a single 50 mg/kg control IgG injection using the same procedure as described in Example 1, and blood samples were taken at 24 hours and 7 days post-dose. Reticulocyte counts were measured in whole blood as described above. The results are shown in FIG. 2C . At 24 hours post-dose, all of the anti-TfR A /BACE1-treated mouse samples showed similar marked reductions in total reticulocyte count.
  • the 25 mg/kg and 50 mg/kg anti-TfR D /BACE1-treated samples showed similarly low reticulocyte counts as the anti-TfR A /BACE1-treated samples.
  • the 5 mg/kg anti-TfR D /BACE1-treated samples showed only a modest reduction in reticulocyte numbers relative to the IgG control sample at 24 hours post-dose.
  • all groups showed normal levels of reticulocytes ( FIG. 2C ) suggesting recovery from the initial reticulocyte depletion, with the exception of the 50 mg/kg anti-TfR D /BACE1 sample, which showed a sustained reduction in reticulocyte levels (approximately 50%) relative to the control amounts.
  • mice treated with high-dose anti-TfR A /BACE1 showed a recovery of reticulocyte numbers by 7 days that corresponded with the faster clearance of this antibody from circulation relative to anti-TfR D /BACE1 (as seen in Example 1, FIG. 1B ).
  • mice were intravenously injected with 50 mg/kg of either control IgG, or anti-TfR/BACE1. Total injection volume did not exceed 250 ⁇ L and antibodies were diluted in D-PBS (Invitrogen) when necessary. After the indicated time, mice were perfused with D-PBS at a rate of 2 mL/min for 8 minutes.
  • Bound antibody was detected with horseradish peroxidase-conjugated F(ab′) 2 goat anti-human IgG, Fc specific polyclonal antibody (Jackson ImmunoResearch), developed using 3,3′,5,5′-tetramethyl benzidine (TMB) (KPL, Inc., Gaithersburg, Md.) and absorbance measured at 450 nm on a Multiskan Ascent reader (Thermo Scientific, Hudson, N.H.). Concentrations were determined from the standard curve using a four-parameter non-linear regression program. The assay had a lower limit of quantification (LLOQ) values of 3.12 ng/ml in serum and 12.81 ng/g in brain. Statistical analysis of differences between experimental groups was performed using two-tailed unpaired t-test.
  • Abeta 1-40 was also detected in brain and plasma. Briefly, mice were treated with antibody and perfused according to the method described above. For Abeta 1-40 measurements, hemi-brains were homogenized in 5 M guanidine hydrochloride buffer and samples rotated for 3 hours at room temperature prior to diluting (1:10) in 0.25% casein, 5 mM EDTA (pH 8.0) in PBS containing freshly added aprotinin (20 mg/mL) and leupeptin (10 mg/ml). Diluted homogenates were spun at 14,000 rpm for 20 min and supernatants were isolated for Abeta 1-40 measurement. Plasma was prepared as described above.
  • the concentrations of total mouse Abeta 1-40 in plasma and brain were determined using a sandwich ELISA following similar procedures described above.
  • Rabbit polyclonal antibody specific for the C-terminus of Abeta 1-40 (Millipore, Bedford, Mass.) was coated onto plates, and biotinylated anti-mouse Abeta monoclonal antibody M3.2 (Covance, Dedham, Mass.) was used for detection.
  • the assay had LLOQ values of 1.96 pg/ml in plasma and 39.1 pg/g in brain.
  • Statistical analysis of differences between experimental groups was performed using two-tailed unpaired t-test.
  • FIG. 2D A robust and sustained reduction in brain Abeta at both 25 and 50 mg/kg dose levels for anti-TfR D /BACE1 was observed ( FIG. 2D ), while anti-TfR A /BACE1 showed a robust, but acute reduction in brain Abeta at all three dose levels ( FIG. 2E ).
  • FIGS. 2F-2H These data were consistent with the observed pharmacokinetics of the compounds in both the periphery and the brain. From these data, it was apparent that a dosage level of 25 mg/kg of anti-TfR D /BACE1 is sufficient to significantly reduce brain Abeta levels in these studies.
  • Reticulocyte depletion by anti-TfR antibody species could be due to a variety of different natural processes, including effector function/antibody-dependent cell-mediated cytotoxicity (ADCC), complement-dependent cytotoxicity (CDC), direct target-mediated lysis/apoptosis, and/or phagocytosis of opsonized reticulocytes by macrophages.
  • ADCC effector function/antibody-dependent cell-mediated cytotoxicity
  • CDC complement-dependent cytotoxicity
  • direct target-mediated lysis/apoptosis and/or phagocytosis of opsonized reticulocytes by macrophages.
  • the monospecific and bispecific anti-TfR antibodies used the preceding experiments also differed in the degree of their effector functions.
  • the monospecific anti-TfR antibodies were produced in CHO cells, and had mammalian-type glycosylation and wild-type effector function.
  • the bispecific anti-TfR/BACE1 antibodies had a severely reduced or eliminated capacity to interact with Fc ⁇ -receptors using one or more of the following methods well-known in the art: abrogating glycosylation due to the presence of the mutation N297G or N297A in the Fc region (Atwal et al., Sci. Transl. Med.
  • Example 2A The mouse studies performed in Example 2A were repeated with these Fc-modified antibodies and also in different mouse strains lacking either Fc ⁇ receptors or complement C3, to evaluate potential mechanisms of reticulocyte depletion including effector-driven ADCC or CDC respectively; whole blood samples were assessed for total reticulocyte counts 24 hours after intravenous injection of the antibody.
  • administration of monospecific 1 mg/kg or 25 mg/kg anti-TfR D lacking effector function to wild-type mice had the same depletive effect on reticulocyte counts as an anti-TfR D antibody with full effector function (compare FIG. 3A with FIG. 2B ).
  • mice treated with the effectorless anti-TfR D antibody in sharp contrast to those treated with an effector-positive anti-TfR D antibody (Example 2A).
  • effector-positive anti-TfR D was administered to mice lacking Fc ⁇ receptor (to eliminate ADCC mechanisms that may be triggered by effector function)
  • reticulocyte levels were reduced to near zero following a dose of 25 mg/kg, but no acute clinical signs were observed ( FIG. 3B ).
  • effector function is not necessary to drive reticulocyte depletion, but clearly contributes to this depletion, particularly at lower dose levels.
  • acute clinical symptoms observed in mice are linked to the effector status of the antibody, such that effectorless antibodies or Fc ⁇ -knockout mice both completely mitigate these symptoms.
  • CDC assays were performed using primary mouse bone marrow cells or mouse erythroleukemic lymphoblasts (HPA Cultures, UK) as target cells and complement derived from rabbit serum (EMD Chemicals, Gibbstown N.J.). Cells were counted and viability determined by Vi-CellTM (Beckman Coulter, Fullerton, Calif.).
  • Anti-TfR A /BACE1, anti-TfR A or negative or positive control antibody (IgG or anti-H2Kb, respectively) were serially diluted 1:4 in assay medium (RPMI-1640 medium supplemented with 20 mM HEPES, pH 7.2 and 1% FBS), and distributed into a white, flat-bottom 96-well tissue culture plate (Costar; Corning, Acton Mass.). Following the addition of serum complement diluted 1:3 in assay medium and the target cells (2 ⁇ 10 5 cells/well), the plate was incubated with 5% CO 2 for 2 hours at 37° C. The plates were then left at room temperature for 10 minutes with constant shaking.
  • assay medium RPMI-1640 medium supplemented with 20 mM HEPES, pH 7.2 and 1% FBS
  • the extent of cell lysis was quantified by measuring luminescence intensity with a SpectroMaxTM M5 plate reader. Luminescence values of sample dilutions were plotted against the antibody concentration, and the dose-response curves were fitted to a four-parameter model using GraphPadTM (GraphPad Software Inc.).
  • ADCC effector function-mediated antibody-dependent cell-mediated cytotoxicity
  • PBMCs were isolated by density gradient centrifugation using a Uni-Sep blood separation tube (Accurate Chemical & Scientific; Westbury, N.Y.).
  • Target cells were prelabled with 1.4 mM solution of calcein AM (Molecule Probes) and were seeded in a 96-well, round-bottom plate (BD Biosciences; Mississauga, Ontario; Canada) at 4 ⁇ 10 4 /well.
  • Serial dilutions of anti-TfR/BACE1, anti-TfR and control antibody were added to the plates containing the target cells, followed by incubation at 37° C. with 5% carbon dioxide for 30 minutes to allow opsonization.
  • the final concentrations of antibodies ranged from 1,000 to 0.004 ng/mL following 4-fold serial dilutions.
  • 1 ⁇ 10 6 PBMC effector cells in 100 ⁇ L assay medium were added to each well to give a ratio of 25:1 effector to target cells, and the plates were incubated for an additional 3 hours.
  • the plates were centrifuged at the end of incubation, and fluorescent signals in supernatants were measured using a SpectraMaxTM M5 microplate reader, with excitation at 485 nm and emission at 520 nm.
  • ADCC antibody-independent cellular cytotoxicity
  • %ADCC 100 ⁇ (Sample signal ⁇ AICC) ⁇ (maximum lysis ⁇ spontaneous release)
  • ADCC values of sample dilutions were plotted against the antibody concentration and the dose response curve fitted with a four-parameter model using GraphPadTM (GraphPad Software Inc.).
  • the anti-TfR A used in this assay had effector function, while the anti-TfR A /BACE1 used in the assay had no effector function.
  • the antibody with effector function induced ADCC while the anti-TfR A /BACE1 antibody lacking effector function did not, correlating with the prior mouse experiment results.
  • F(ab′) 2 fragments were generated from anti-TfR IgG, anti-TfR/IgG or anti-TfR/BACE1 antibodies by digestion with immobilized pepsin.
  • the antibody was reconstituted in 100 mM sodium acetate, pH 4.2 and incubated with immobilized pepsin resin (0.3 mL settled gel/mg IgG) overnight at 37° C. with rotation.
  • the sample was centrifuged to separate the immobilized pepsin from the F(ab′) 2 -digested mixture.
  • the F(ab′) 2 fragment was then purified using an SP sepharose, strong cation-exchange resin (1 mL HiTrapTM column (Supelco)).
  • the sample was loaded in 50 mM NaOAc pH 5.0 and eluted with a 0-0.5 M NaCl gradient over 20 column volumes after which the sample was dialyzed against PBS, pH 7.4.
  • bispecific F(ab′) 2 antibodies further underscores the conclusion that the Fc region is not necessary for reticulocyte depletion to occur.
  • Bispecific antibodies lacking the BACE1 arm depleted reticulocytes to the same degree as anti-TfR D /BACE1 ( FIG. 5C ), demonstrating that the BACE1 arm also does not contribute to reticulocyte elimination.
  • anti-TfR E /BACE1 had better sustained plasma exposure and persistence in the brain, but less robust transport across the blood-brain barrier than anti-TfR D /BACE1.
  • anti-TfR D /BACE1 administration resulted in reticulocyte depletion but anti-TfR E /BACE1 administration did not, variant anti-TfRs with affinities between that of anti-TfR D and anti-TfR E for TfR were generated to see if the safety profile of the antibody could be improved without sacrificing BBB transport and persistence in brain.
  • site-directed mutagenesis was employed to combine the two point mutations representing the anti-TfR D and anti-TfR B variants respectively into a single antibody designated anti-TfR Db using standard mutagenesis techniques.
  • Both antibodies were made into a bispecific format with anti-BACE1 using knob and hole technology as described in Example 2C.
  • the plasma antibody concentration of both new variant antibodies over time, the brain antibody concentration (both the maximum value and the decrease over time), and the reduction in A ⁇ 1-40 was between that of anti-TfR D /BACE1 and anti-TfR E /BACE1 when administered at the same dose level.
  • mice were treated with a single dose of anti-TfR A /BACE1 or anti-TfR D /BACE1 at 5, 25 or 50 mg/kg, and TfR expression in brain was evaluated at 4 days post-dose via Western blot.
  • Brains from antibody-treated mice were PBS perfused before extraction, and isolated cortex and hippocampus were homogenized in 1% NP-40 (Calbiochem) in PBS containing Complete Mini EDTA-free protease inhibitor tables (Roche Diagnostics). Homogenized brains were rotated at 4° C. for 1 hour before spinning at 14,000 rpm for 20 minutes.
  • a concern of exploiting a blood-brain barrier transport receptor for transport of heterologous molecules into the brain is that the BBB itself might be impaired. Accordingly, the permeability of the BBB to antibodies upon dosing with anti-TfR was investigated. Wild-type mice were intravenously administered 50 mg/kg of control IgG, or 25 mg/kg of each of the indicated co-injected antibody combinations. Mean antibody uptake in brain 24 hours after intravenous injection was assessed using a generic human-Fc ELISA according to Example 1 or using an anti-BACE1 specific ELISA following similar procedures to those described in Example 1.
  • the BACE1 extracellular domain was used as the coat protein and detection was performed with horseradish peroxidase-conjugated F(ab′) 2 goat anti-human IgG, Fc-specific polyclonal antibody.
  • This assay had LLOQ values of approximately 2.56 ng/g for anti-BACE1 and 12.8 ng/g for anti-TfR D /BACE1.
  • Brain A ⁇ 1-40 levels were measured after administration using the same procedure set forth in Example 1.
  • FIGS. 7A-7C Brain antibody exposure was highest in the control IgG+ anti-TfR D /BACE1-treated mice, but also substantial in the mice treated with anti-TfR D -containing antibody combinations ( FIG. 7A ). This correlates with the results in Example 1 in that the lower-affinity bispecific form of anti-TfR D is taken up and persists in the brain longer than the higher-affinity monospecific form of anti-TfR D .
  • Antibodies coadministered with the anti-TfR antibody were not taken up into the brain in substantial quantities; the only anti-BACE1 observed in substantial quantity in the brain was that directly conjugated to anti-TfR D ( FIG. 7B ).
  • the serum antibody concentration for anti-TfR D /BACE1 was similar over time after 2 or 4 doses, suggesting that clearance in the mouse bloodstream does not substantially differ after repeated dosing ( FIG. 8A ).
  • a slight decrease in overall antibody exposure was apparent 4 days after the fourth dose relative to the same time after the second dose, suggestive of the occurrence of mouse anti-drug antibodies (ADAs) to the administered human IgG antibodies.
  • brain antibody concentrations were decreased by 4 days after the fourth dose, although the persistence of the antibodies present in the brain over time mirrored that observed after the second dose ( FIG. 8B ).
  • Plasma ( FIG. 8C ) and brain ( FIG. 8D ) levels of Abeta1-40 correlated well with the observed amounts of anti-TfR D /BACE1 present in the serum and brain after 2 or 4 doses.
  • Orbital bleeds were used for blood extraction after isofluorane anesthesia, and bone marrow from one femur was harvested and single cell suspensions were prepared. Cells were then filtered through a 70-micron cell strainer. Cells were washed and resuspended in a set volume of PBS. A fixed volume of cell suspension was added to a fixed concentration of FITC-labeled fluorescent beads and analyzed on a flow cytometer, collecting 5000 bead events per sample to obtain cell counts. Quantitative analysis of erythroid populations was determined by flow cytometry.
  • samples were incubated for 20 minutes on ice with anti-mouse Ter119-PE (eBioscience) and biotinylated anti-mouse TfR, followed by streptavidin-eFluor450 (eBioscience). Samples were washed with PBS containing 0.5% BSA, 2 mM EDTA and run on a BD LSR Fortessa multi-color flow cytometer and analyzed using FlowJo software (Ashland, Oreg.).
  • wild-type mice were given a single IV dose of 25 mg/kg of anti-TfR A /BACE1 (Fc ⁇ ), anti-TfR D /BACE1 (Fc ⁇ ), anti-TfR D /BACE1 (Fc+), or control IgG (where “Fc ⁇ ” indicates an effectorless antibody due to the presence of mutations D265A and N297G or to lack of glycosylation and “Fc+” indicates an antibody with wild-type effector function), following the same injection and sample collection process as above.
  • Fc ⁇ indicates an effectorless antibody due to the presence of mutations D265A and N297G or to lack of glycosylation
  • Fc+ indicates an antibody with wild-type effector function
  • ADCC assays were carried out using peripheral blood mononuclear cells (PBMCs) from healthy human donors as effector cells.
  • PBMCs peripheral blood mononuclear cells
  • a human erythroleukemia cell line (HEL, ATCC) and primary human bone marrow mononuclear cells (AllCells, Inc.) were used as target cells.
  • HEL erythroleukemia cell line
  • AllCells, Inc. primary human bone marrow mononuclear cells
  • HEL cells were used as the target cells, with PBMCs from healthy human donors carrying either the F/V158 genotype or the Fc ⁇ RIIIA V/V158 genotype.
  • the V/V158 genotype was also included in this assay due to the known association with increased NK cell-mediated ADCC activity as well as ability to bind IgG4 antibodies (Bowles and Weiner, 2005; Bruhns et al. 2008). Cells were counted and viability was determined by Vi-CELL® (Beckman Coulter; Fullerton, Calif.) following the manufacturer's instructions.
  • PBMCs peripheral blood mononuclear cells
  • PBMCs peripheral blood mononuclear cells
  • Assay medium RPMI-1640 with 1% BSA and 100 units/mL penicillin and streptomycin
  • Serial dilutions of test and control antibodies 50 ⁇ L/well were added to the plates containing the target cells, followed by incubation at 37° C. with 5% CO 2 for 30 minutes to allow opsonization.
  • the final concentrations of antibodies ranged from 0.0051 to 10,000 ng/mL following 5-fold serial dilutions for a total of 10 data points.
  • 1.0 ⁇ 10 6 PBMC effector cells in 100 ⁇ L of assay medium were added to each well to give a ratio of 25:1 effector: target cells, and the plates were incubated for an additional 4 hours.
  • the plates were centrifuged at the end of incubation and the supernatants were tested for lactate dehydrogenase (LDH) activity using a Cytotoxicity Detection KitTM (Roche Applied Science; Indianapolis, Ind.).
  • LDH lactate dehydrogenase
  • the LDH reaction mixture was added to the supernatants and the plates were incubated at room temperature for 15 minutes with constant shaking.
  • the reaction was terminated with 1 M H 3 PO 4 , and absorbance was measured at 490 nm (the background, measured at 650 nm was subtracted for each well) using a SpectraMax Plus microplate reader. Absorbance of wells containing only the target cells served as the control for the background (low control), whereas wells containing target cells lysed with Triton-X100 provided the maximum signal available (high control). Antibody-independent cellular cytotoxicity (AICC) was measured in wells containing target and effector cells without the addition of antibody. The extent of specific ADCC was calculated as follows:
  • % ⁇ ⁇ ADCC 100 ⁇ A 490 ⁇ ( Sample ) - A 490 ⁇ ( AICC ) A 490 ⁇ ( High ⁇ ⁇ Control ) - A 490 ⁇ ( Low ⁇ ⁇ Control )
  • ADCC values of sample dilutions were plotted against the antibody concentration, and the dose-response curves were fitted to a four-parameter model using SoftMax Pro.
  • the ADCC activity of various anti-human TfR constructs were assessed using either a human erythroleukemia cell line (HEL cells) or primary human bone marrow mononuclear cells as the target cells.
  • HEL cells human erythroleukemia cell line
  • Bivalent IgG1 effector function-competent anti-human TfR1 antibody 15G11 and a bispecific form of this antibody with the same anti-BACE1 arm used in the prior examples in a human IgG1 format with the D265A and N297G mutations abrogating effector function (see Example 6) were tested at various concentrations in the ADCC assay, using anti-gD WT IgG1 as a negative control and murine anti-human HLA (class I) as a positive control.
  • FIGS. 13A and 13B The results are shown in FIGS. 13A and 13B .
  • the monospecific anti-human TfR antibody 15G11 elicited significant ADCC activity. This activity was similar to that of the positive control anti-human HLA antibodies on the HEL cells, and at a robust yet lower level than the positive control on the bone marrow mononuclear cells.
  • the somewhat lower level observed in the bone marrow mononuclear cells experiment is likely due to the fact that only a portion of the heterogenous mixture of myeloid and erythroid lineage PBMC cells used in the experiment express high levels of TfR, whereas the HEL cells have consistently high TfR expression throughout the clonal cell population.
  • the bispecific effectorless anti-humanTfR/BACE1 antibody did not display any ADCC activity in either HEL or bone marrow mononuclear cells, similar to the negative control.
  • the ADCC assay procedure was identical to that described above, with the exception that all target cells were HEL cells, and the effector cells were PBMCs from healthy human donors either carrying the heterozygous Fc ⁇ RIIIa-V/F158 genotype or the homozygous Fc ⁇ RIIIa-V/V158 genotype. All anti-human TfR tested were bispecific with anti-gD, with three different Ig backbones: wild-type human IgG1, human IgG1 with the N297G mutation, and human IgG4.
  • FIGS. 14A and 14B An anti-Abeta antibody with a human IgG4 backbone was also tested, and mouse anti-human HLA (class I) served as a positive control. The results are shown in FIGS. 14A and 14B . As anticipated based on the known association between effector cell activation and the V/V158 genotype (Bowles and Weiner 2005), ADCC activity was more robustly elicited by V/V158 donor PBMCs ( ⁇ 45% of target cells impacted) relative to F/V158 donors ( ⁇ 25% of target cells impacted) (compare FIG. 14A to FIG. 14B ).
  • Anti-TfR/gD with the wild-type IgG1 induced robust ADCC in HEL cells, while the anti-TfR/gD with the effectorless IgG1 did not show any ADCC activity in HEL cells, replicating the results from the first set of experiments.
  • anti-TfR/gD of the IgG4 isotype showed a mild ADCC activity. This activity was not observed in the anti-Abeta IgG4 results, indicating that TfR binding was required for the ADCC activity. This finding correlates with previous reports that IgG4 has minimal, but measurable, effector function (Adolffson et al., J. Neurosci.

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Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US10870837B2 (en) 2017-10-02 2020-12-22 Denali Therapeutics Inc. Fusion proteins comprising enzyme replacement therapy enzymes
US10941205B2 (en) 2015-10-02 2021-03-09 Hoffmann-La Roche Inc. Bispecific anti-human A-beta/human transferrin receptor antibodies and methods of use
US11267896B2 (en) 2015-05-04 2022-03-08 Cytomx Therapeutics, Inc. Anti-CD71 antibodies, activatable anti-CD71 antibodies, and methods of use thereof
US11584793B2 (en) 2015-06-24 2023-02-21 Hoffmann-La Roche Inc. Anti-transferrin receptor antibodies with tailored affinity
US11603411B2 (en) 2015-10-02 2023-03-14 Hoffmann-La Roche Inc. Bispecific anti-human CD20/human transferrin receptor antibodies and methods of use
US11795232B2 (en) 2017-02-17 2023-10-24 Denali Therapeutics Inc. Engineered transferrin receptor binding polypeptides
US11896673B2 (en) 2016-01-14 2024-02-13 North Carolina State University Glucose responsive insulin delivery compositions and methods

Families Citing this family (37)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
BR112013002578A2 (pt) 2010-08-03 2019-05-14 Abbvie Inc. imunoglobinas de domínio variável duplo e usos das mesmas
SG190682A1 (en) 2010-11-10 2013-07-31 Genentech Inc Methods and compositions for neural disease immunotherapy
US9580486B2 (en) 2013-03-14 2017-02-28 Amgen Inc. Interleukin-2 muteins for the expansion of T-regulatory cells
MX2015013181A (es) 2013-03-15 2015-12-11 Amgen Inc Anticuerpos humanos pac1.
CA2908743A1 (en) * 2013-05-20 2014-11-27 Genentech, Inc. Anti-transferrin receptor antibodies and methods of use
PE20161311A1 (es) * 2014-03-06 2016-11-25 Nat Res Council Canada Anticuerpos especificos del receptor del factor 1 de crecimiento similar a la insulina y usos de los mismos.
RU2705299C2 (ru) * 2014-06-26 2019-11-06 Ф. Хоффманн-Ля Рош Аг Антитела против 5-бром-2'-дезоксиуридина и способы применения
TW201620938A (zh) 2014-09-15 2016-06-16 安美基公司 雙特異性抗cgrp受體/pac1受體抗原結合蛋白質及其用途
EP3218411B1 (en) 2014-11-14 2022-01-12 Ossianix, Inc. Variable new antigen receptors (vnars) directed against transferrin receptor (tfr) and their use
JP6859259B2 (ja) 2014-11-19 2021-04-14 ジェネンテック， インコーポレイテッド ＢＡＣＥｌに対する抗体及び神経疾患免疫療法のためのその使用
EP3221362B1 (en) 2014-11-19 2019-07-24 F.Hoffmann-La Roche Ag Anti-transferrin receptor antibodies and methods of use
EP3221361B1 (en) 2014-11-19 2021-04-21 Genentech, Inc. Anti-transferrin receptor / anti-bace1 multispecific antibodies and methods of use
SG11201703750XA (en) * 2014-12-10 2017-06-29 Genentech Inc Blood brain barrier receptor antibodies and methods of use
WO2016094881A2 (en) 2014-12-11 2016-06-16 Abbvie Inc. Lrp-8 binding proteins
IL283764B2 (en) 2015-04-10 2024-01-01 Amgen Inc Interleukin for the expansion of myotonic control T-2 cells
TW201710286A (zh) 2015-06-15 2017-03-16 艾伯維有限公司 抗ｖｅｇｆ、ｐｄｇｆ及／或其受體之結合蛋白
WO2016208696A1 (ja) * 2015-06-24 2016-12-29 Ｊｃｒファーマ株式会社 Ｂｄｎｆを含む融合蛋白質
CA2990785A1 (en) * 2015-06-24 2016-12-29 Jcr Pharmaceuticals Co., Ltd. Anti-human transferrin receptor antibody permeating blood-brain barrier
GB2541003A (en) * 2015-08-05 2017-02-08 Kran Life Sciences Llp Neurodegenerative disorders
EP3390447A1 (en) 2015-12-15 2018-10-24 Amgen Inc. Pacap antibodies and uses thereof
CN107375280B (zh) * 2016-05-17 2021-03-05 中国科学院上海药物研究所 硝唑尼特及其药学上可接受的盐在制备用于治疗阿尔茨海默病的药物中的应用
AU2017311040B2 (en) 2016-08-06 2023-08-31 Ossianix, Inc. In vivo methods for selecting peptides that cross the blood brain barrier, related compositions and methods of use
MA45919A (fr) 2016-08-12 2019-06-19 Janssen Biotech Inc Conception d'anticorps modifiés et d'autres molécules contenant un domaine fc présentant des fonctions d'agonisme et d'effecteur améliorées
KR102497564B1 (ko) 2016-12-26 2023-02-07 제이씨알 파마 가부시키가이샤 혈액뇌관문을 통과하는 신규한 항인간 트랜스페린 수용체 항체
KR102573622B1 (ko) 2016-12-26 2023-08-31 제이씨알 파마 가부시키가이샤 Bdnf를 포함하는 융합 단백질
US20180299436A1 (en) * 2017-01-20 2018-10-18 Shenzhen New Industries Biomedical Engineering Co., Ltd. A method, kit and system for preparing an antibody pair and the use of the kit
US10143187B2 (en) 2017-02-17 2018-12-04 Denali Therapeutics Inc. Transferrin receptor transgenic models
US10457717B2 (en) 2017-02-17 2019-10-29 Denali Therapeutics Inc. Engineered polypeptides
WO2019094608A1 (en) * 2017-11-08 2019-05-16 Denali Therapeutics Inc. Anti-bace1 antibodies and methods of use thereof
WO2019140050A1 (en) * 2018-01-10 2019-07-18 Denali Therapeutics Inc. Transferrin receptor-binding polypeptides and uses thereof
EP3737699A1 (en) 2018-01-12 2020-11-18 Amgen Inc. Pac1 antibodies and uses thereof
ES2929416T3 (es) 2018-06-21 2022-11-29 Novo Nordisk As Nuevos compuestos para el tratamiento de la obesidad
WO2020056327A1 (en) 2018-09-14 2020-03-19 Ossianix, Inc. Tfr-specific binding moieties and transcytosis method to select vnars that cross cellular barriers
US20220048961A1 (en) * 2018-12-14 2022-02-17 Fred Hutchinson Cancer Research Center Transferrin receptor targeting peptides
WO2020138487A1 (ja) * 2018-12-28 2020-07-02 協和キリン株式会社 ＴｆＲに結合するバイスペシフィック抗体
CA3124790A1 (en) 2019-01-09 2020-07-16 Vect-Horus Transferrin receptor-binding molecules, conjugates thereof and their uses
WO2022039887A1 (en) * 2020-08-21 2022-02-24 Vyluma Inc. Low-dose ophthalmic compositions and methods

Family Cites Families (46)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3773919A (en) 1969-10-23 1973-11-20 Du Pont Polylactide-drug mixtures
US4816567A (en) 1983-04-08 1989-03-28 Genentech, Inc. Recombinant immunoglobin preparations
US4676980A (en) 1985-09-23 1987-06-30 The United States Of America As Represented By The Secretary Of The Department Of Health And Human Services Target specific cross-linked heteroantibodies
US5567610A (en) 1986-09-04 1996-10-22 Bioinvent International Ab Method of producing human monoclonal antibodies and kit therefor
GB8823869D0 (en) 1988-10-12 1988-11-16 Medical Res Council Production of antibodies
US5175384A (en) 1988-12-05 1992-12-29 Genpharm International Transgenic mice depleted in mature t-cells and methods for making transgenic mice
US5672683A (en) 1989-09-07 1997-09-30 Alkermes, Inc. Transferrin neuropharmaceutical agent fusion protein
US5208020A (en) 1989-10-25 1993-05-04 Immunogen Inc. Cytotoxic agents comprising maytansinoids and their therapeutic use
US5229275A (en) 1990-04-26 1993-07-20 Akzo N.V. In-vitro method for producing antigen-specific human monoclonal antibodies
IE922437A1 (en) 1991-07-25 1993-01-27 Idec Pharma Corp Recombinant antibodies for human therapy
ES2136092T3 (es) 1991-09-23 1999-11-16 Medical Res Council Procedimientos para la produccion de anticuerpos humanizados.
WO1993008829A1 (en) 1991-11-04 1993-05-13 The Regents Of The University Of California Compositions that mediate killing of hiv-infected cells
JP3571337B2 (ja) 1992-02-11 2004-09-29 セル ジェネシス，インコーポレーテッド 遺伝子標的現象による同型遺伝子接合
US5573905A (en) 1992-03-30 1996-11-12 The Scripps Research Institute Encoded combinatorial chemical libraries
ATE191853T1 (de) 1992-07-27 2000-05-15 Us Health Zielgerichte liposome zur blut-hirne schranke
US5731168A (en) 1995-03-01 1998-03-24 Genentech, Inc. Method for making heteromultimeric polypeptides
GB9603256D0 (en) 1996-02-16 1996-04-17 Wellcome Found Antibodies
EP0994903B1 (en) 1997-06-24 2005-05-25 Genentech, Inc. Methods and compositions for galactosylated glycoproteins
AU759779B2 (en) 1997-10-31 2003-05-01 Genentech Inc. Methods and compositions comprising glycoprotein glycoforms
ATE375365T1 (de) 1998-04-02 2007-10-15 Genentech Inc Antikörper varianten und fragmente davon
DK2180007T4 (da) 1998-04-20 2017-11-27 Roche Glycart Ag Glycosyleringsteknik for antistoffer til forbedring af antistofafhængig cellecytotoxicitet
KR101077001B1 (ko) 1999-01-15 2011-10-26 제넨테크, 인크. 효과기 기능이 변화된 폴리펩티드 변이체
US6737056B1 (en) 1999-01-15 2004-05-18 Genentech, Inc. Polypeptide variants with altered effector function
US6582945B1 (en) 1999-06-16 2003-06-24 Boston Biomedical Research Institute Immunological control of β-amyloid levels in vivo
US6949245B1 (en) 1999-06-25 2005-09-27 Genentech, Inc. Humanized anti-ErbB2 antibodies and treatment with anti-ErbB2 antibodies
DE19947010A1 (de) 1999-09-30 2001-04-05 Universitaetsklinikum Freiburg Das Gen PRV-1 und dessen Verwendung
DK2857516T3 (en) 2000-04-11 2017-08-07 Genentech Inc Multivalent antibodies and uses thereof
MXPA04001072A (es) 2001-08-03 2005-02-17 Glycart Biotechnology Ag Variantes de glicosilacion de anticuerpos que tienen citotoxicidad celulares dependiente de anticuerpos incrementada.
KR100988949B1 (ko) 2001-10-25 2010-10-20 제넨테크, 인크. 당단백질 조성물
US20040093621A1 (en) 2001-12-25 2004-05-13 Kyowa Hakko Kogyo Co., Ltd Antibody composition which specifically binds to CD20
US20050142141A1 (en) 2002-11-27 2005-06-30 Pardridge William M. Delivery of enzymes to the brain
JP5036302B2 (ja) * 2003-02-10 2012-09-26 ティオー − ビービービー ホールディング ベスローテン フェンノートシャップ 炎症状態下に血液脳関門で示差的（ｄｉｆｆｅｒｅｎｔｉａｌｌｙ）に発現される核酸
LT2380911T (lt) 2003-11-05 2018-07-10 Roche Glycart Ag Antigeną surišančios molekulės, pasižyminčios padidintu fc receptoriaus surišimo afiniškumu ir efektoriaus funkcija
US8053569B2 (en) 2005-10-07 2011-11-08 Armagen Technologies, Inc. Nucleic acids encoding and methods of producing fusion proteins
BRPI0619748B8 (pt) 2005-12-12 2021-05-25 Ac Immune Sa anticorpo monoclonal, polinucleotídeo, composição, mistura, uso de um anticorpo monoclonal ou uma parte funcional do mesmo, método para preparar uma composição farmacêutica, linhagem celular de hibridoma isolado, método de diagnóstico de uma doença ou condição associada a amilóide em um paciente, método para diagnosticar uma predisposição para uma doença ou condição, método para monitorar doença residual mínima, método para prever a responsividade de um paciente e kits de teste
CA2647808C (en) 2006-03-30 2015-11-17 Glaxo Group Limited Antibodies against amyloid-beta peptide
CA2657681C (en) 2006-07-14 2019-03-19 Ac Immune S.A. Humanized antibodies against beta amyloid protein
CN101541972A (zh) 2006-08-04 2009-09-23 都柏林城市大学 生产重组生物产品的方法
US8759297B2 (en) * 2006-08-18 2014-06-24 Armagen Technologies, Inc. Genetically encoded multifunctional compositions bidirectionally transported between peripheral blood and the cns
EP2471816A1 (en) 2006-08-30 2012-07-04 Genentech, Inc. Multispecific antibodies
NZ576032A (en) 2006-10-12 2012-03-30 Genentech Inc Antibodies to lymphotoxin-alpha
CN101245107B (zh) 2007-02-14 2010-10-13 中国人民解放军军事医学科学院生物工程研究所 抗人转铁蛋白受体人源抗体及其应用
AR066987A1 (es) 2007-06-12 2009-09-23 Ac Immune Sa Anticuerpo monoclonal contra proteina beta-amiloide
JP2010530744A (ja) 2007-06-12 2010-09-16 エーシー イミューン ソシエテ アノニム アミロイドβに対するヒト化抗体
EP2235064B1 (en) 2008-01-07 2015-11-25 Amgen Inc. Method for making antibody fc-heterodimeric molecules using electrostatic steering effects
EP2646470B1 (en) 2010-11-30 2017-03-01 F. Hoffmann-La Roche AG Low affinity anti-transferrin receptor antibodies and their use to transfer therapeutic scfv across the blood brain barrier

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
Jackowski, British Journal of Neurosurgery 9: 303-317 (1995). *

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US11267896B2 (en) 2015-05-04 2022-03-08 Cytomx Therapeutics, Inc. Anti-CD71 antibodies, activatable anti-CD71 antibodies, and methods of use thereof
US11584793B2 (en) 2015-06-24 2023-02-21 Hoffmann-La Roche Inc. Anti-transferrin receptor antibodies with tailored affinity
US10941205B2 (en) 2015-10-02 2021-03-09 Hoffmann-La Roche Inc. Bispecific anti-human A-beta/human transferrin receptor antibodies and methods of use
US11603411B2 (en) 2015-10-02 2023-03-14 Hoffmann-La Roche Inc. Bispecific anti-human CD20/human transferrin receptor antibodies and methods of use
US11787868B2 (en) 2015-10-02 2023-10-17 Hoffmann-La Roche Inc. Bispecific anti-human A-beta/human transferrin receptor antibodies and methods of use
US11896673B2 (en) 2016-01-14 2024-02-13 North Carolina State University Glucose responsive insulin delivery compositions and methods
US11795232B2 (en) 2017-02-17 2023-10-24 Denali Therapeutics Inc. Engineered transferrin receptor binding polypeptides
US11912778B2 (en) 2017-02-17 2024-02-27 Denali Therapeutics Inc. Methods of engineering transferrin receptor binding polypeptides
US10870837B2 (en) 2017-10-02 2020-12-22 Denali Therapeutics Inc. Fusion proteins comprising enzyme replacement therapy enzymes
US11866742B2 (en) 2017-10-02 2024-01-09 Denali Therapeutics Inc. Fusion proteins comprising enzyme replacement therapy enzymes

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