CA2175457A1 - Treatment for rheumatoid arthritis - Google Patents

Abstract

Administration of corticotropin-releasing factor to patients suffering from one of the chronic inflammatory athritides, such as rheumatoid arthritis, reduces episodic acute inflammatory responses to the chronic disease. Doses of administered CRF in accordance with the invention give anti-inflammatory results in a dose responsive manner even in well-established disease.

Description

21~57 ~7~TM~NT FOR }~ JIu ARTlIRI~3:5 Fiela of the Invention This invention generally relates to a method 5 of treating a patient suffering from a chronic inflam-matory arthritides, and more particularly to the use of corticotropin-releasing factor or its analogs in reducing swelling during episodic acute responses of chronic inflammatory conditions.
l0 Backqround of the Invention Among the diseases that plague humans are the chronic inflammatory arthritides, which include rheuma-toid arthritis, Reiters Syndrome, ankylosing spondyitis, psoriatic arthritis, and infl2 tory bowel disease. of 15 these, rheumatoid arthritis is the cause of an estimated about 33, 000 deat1ls in the United States each year. As yet, there is no cure for the disea6e, and the cause is uncertain. Rheumatoid arthritis sufferers periodically experience flare-ups, or episodic acute responses, of 20 from a week up to a month of duration.
Steinman, "Autoimmune Disease, " Scientific ~zeric~n, pp. 107-ll~ (September 1993) discusses several possible new approaches to treating an autoimmune disease, such as rheumatoid arthritis. In one, decoys 25 are being designed to fit into the HLA (human lymphocyte antigen) cleft in an attempt to turn off T cells. In another, a monoclonal antibody that binds with tumor necrosis factor appears to increase ~oint mobility and reduce the stiffness associated with rheumatoid WO 95/12416 PCrNS9~/12621 2f 75457 arthritis. However, these possible new approache6 are as yet not therapeutically established as to efficacy.
Assisting in the search for treatments is the fact that animal models have been develo~?ed using 5 arthritis-susceptible rat strains. Among other possible abnormalities, the "Lewis" arthritis-susceptible rats have a deficient hypothalamic CRF response to various stimuli so that researchers can experimentally induce inflammatory arthritis and some other autoimmune lO diseases. In the Piebald-Viral-Glaxo ("PVG") rat model, unlike the Lewis strain rat, the animals do not appear to have a hypothalmo-pituitary-adrenal ("HPA") axis defect, but are nevertheless susceptible to arthritis.
U.S. Patent ~,006,330, issued April 9, l99l, 15 inventors Sternberg et al., describes use of the Lewis rat animal model in which the experimental animals developed an arthritis which mimics human rheumatoid arthritis in response to exposure to Group A strepto-coccal cell wall fragments. Sternberg et al. teach use 20 of the model for testing the susceptibility of mammals to inflammatory diseases.- Sternberg et al. describe measuring "CRH" (corticotropin-releasing hormone) after injections of various agents. CRH is an alternative term for corticotropin-releasing factor ~hereinafter 25 "CRF"), which is a 41 amino acid neuropeptide that is present in brain and the peripheral nerve endings, and stimulates ACTH release from pituitary cells in brain and such diverse peripheral locations as nerve endings and leukocytes. Sternberg et al. also describe 30 injections of CRH followed by measurements of ACTH and corticosterone .
Antibodies directed against CRF have been reported to partially abrogate the inf lammatory response, which has led various researchers to believe 35 that CRF is a pro-inflammatory agent. Karalis et al., "Autocrine or paracrine Inflammatory Actions of 2 ~ 7 ~ 4 5 7 PCTIUS94/12621 Corticotropin-Releasing Hormone in Vivo," Science, 254, 421-423 (1991).
U.S. Patent 4,489,163, inventors Rivier et al., issued December 18, 1984, discloses rat C~F and its analogs. Human CRF has the same sequence as rat CRF.
There are a number of analogs of CRF known to the art.
U. S . Patent 4 , 415 , 558 , inventors Vale, Jr . et al ., issued November 15, 1983, discloses the synthesis of sheep CRF, analogs, and isolation of the oCRF from ovine hypothalamic extracts. The synthetic oCRF was found to lower blood pressure.
A generally similar peptide, sauvagine, was described in Regulatory Peptides, 2, pp. 1-13 (1981).
Sauvagine is a 4 0 amino acid peptide and has been reported to have biological activity in lowering blood preseure in mammals and stimulating the secretion of ACT~ and ,~-endorphin.
U . S . Patent 4, 528 ,189, inventors Lederis et al., issued July 9, 1985, and U.S. Patent 4,533,654, inventors Lederis et al., issued August 6, 1985, disclose peptides similar to the rat and sheep CRF and analogs thereof, and found this white sucker and carp urotensin respectively to stimulate ACTH and to lower blood pressure. The CRF-related peptide, white sucker urotensin, has an amino acid sequence the same as the carp urotensin, except the amino acid at the 24 position is Isoleucine and the amino acid at the 27 position is Glutamic Acid.
Ling et al., BBRC, 122, pp. 1218-1224 (1984), disclose the structure of goat CRF, which is the same as that for sheep CRF. Esch et al., BBRC, 122, pp. 899-905 (1984), disclose the structure of bovine CRF which differs from sheep and goat CRF only by one amino acid residue (number 33 which is Asparagine rather than the number 33 Serine of goat and sheep CRF). Porcine CRF
has been isolated and characterized by Patthy et al., WO 95/12416 PCr/US9~/12621 Proc. Nat~. Acad. sci., 82, pp. 8762-8766 (1985). Por-cine CRF shares a common amino acid sequence (residues 1-39) with rat/human CRF and differs from these only in position 40 and 41. Residue 40 can be either asparagine 5 or isoleucine and residue 41 is phenylalanine-amide.
U.S. Patent 4,801,612, inventor Wei, issued January 31, 1989, discloses the Use of inhibiting an inflammatory response (acute) in the skin or mucosal membranes of a patient by administering Corticotropin-10 Releasing Factor, or its analogs, and U.S. Patent5,137,871, issued August 11, 1992, inventor Wei, describes the use of CRF (or a salt ~or analog thereof ) in treating a patient for injury to or disease of the brain, nervous system, or musculature in which edema is 15 a factor.
S~ rY of the Invention Administration of corticotropin-releasing factor to patients suffering from one of the chronic inflammatory arthritides, such as rheumatoid arthritis, 20 reduces episodic acute inflammatory responses to the disease. Doses of CRF in accordance with the invention give anti-inflammatory results in a dose responsive manner even in well-established disease. Thus, practice of the invention provides a therapeutic treatment f or 25 these unremitting diseases that are refractory to current therapies.
Therapeutic treatment in accordance with the invention will be under the supervision of a health care professional, usually a physician, and may be in 30 conjunction with other drugs and treatments. Because anti-inflammatory effects and other ameliorating results are experienced within several days when treating episodic acute inflammatory responses that typically would otherwise last for one week up to months, patients 35 receive effective relief ~ of uncomfortable or even ~ 7~4~:~

in-~Ara-~itating symptoms in an inventive course of treatment, although practice of the invention is not a cure .
B~ief DescriDtion of the Drawinqs Figure 1 is a perspective view illustrating the paws of two mycobacterium induced arthritis-susceptible male Lewis "LEW/N" rats where paw 10 is a control and paw 12 has been injected with Mycobacterium to induce arthritis;
Figure 2 graphically illustrates foot pad swelling (with one unit equivalent to 0. 001 inches) in an animal model of arthritis-susceptible rats as a function of time ~or control animals and animals treated in accordance with the invention at two different doses (50 and 100 ~g CRF; injected subcutaneously, per kg of body weight), with the foot pad swelling measurement being made of mycobacterium injected paws (left hind);
Figure 3 is similar to Fig. 2, but illustrates measurements of the paws opposite to the inj ected paws in the transverse plane (right hind);
Figure 4 graphically illustrates the plot of arthritis scores as a function of time for the right hind paw of Fig. 3;
Figure 5 is similar to Fig. 4, but is of the other pair of paws (left and right front);
Figure 6, including panels A-E, is similar to Fig. 2 but plots the larger dose (100 ~g/kg body weight) administered subcutaneously in the mycobacterium injected foot pad (left hind) in accordance with the invention beginning at times delayed up to 40 days a~ter induction of disease;
Figure 7, including panels A-E, is similar to Fig . 6 but is of the opposite f oot pad in the traverse plane (right hind); and WO 95112416 PCrlUS94/12621 ~1 75~57 Figure 8 graphically illustrates plots of arthritis scores in a manner similar to that of Fig. 4, but in the format similar to that of Fig. 6.
De~; 1 ed DescriPtion of the Pref erred ~hr,~ i r ' c It is possible that earlier reports, which found the presence of CRF in the joints of mammals with inf lammatory arthritis and suggested CRF was a pro-inf lammatory agent, may be correct because it is possible that the peptide may be either pro-inflammatory or anti-inflammatory, depending upon the amount of endogenous peptide produced, how the "inflammatory" cell responds to CRF or when CRF appears during the course of the inflammatory response. However, the following description of the work demonstrates that administration of CRF can be therapeutically effective in inhibiting episodic acute and chronic inf lammatory responses in a dose-responsive manner, and therefore this invention is a therapeutic method for treating patients with chronic inflammatory arthritides, such as rheumatoid arthritis.
Practice of this invention uses CRF. By "CRF"
are meant to be included the analogs and CRF-related peptides known to the art . Therapeutic f ormations of CRF may be prepared for storage by mixing CRF having the desired degree of purity with optional physiologically acceptable carriers, excipients or stabilizers, in the form of lyophilized cake or aqueous solutions.
Acceptable carriers, excipients or stabilizers are nontoxic to recipients at the dosages and concentratiOns employed when administered, and include buffers such as phosphate, citrate, and other organic acids; anti-oxidants including ascorbic acid; low molecular weight (less than about lO residues) polypeptides; proteins, such as serum albumin, gelatin or immunoglobulins.
other components can include glycine, glutamine, 35 asparagine, arginine, or lysine; monosaccharides, f ~ u~
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disaccharides, and other carbohydrates including glucose, mannose, or dextrins; chelating agents such as EDTA; sugar alcohols such as mannitol or sorbitol: salt-forming counterions such as sodium; and/or nonionic 5 surfactants such as TWEEN, PLURONICS, or PEG.
Administration may be by any mode of admini-stration known in the art, including, but not limited to, intra-articular, intravenous, intrathecal, subcu-taneous, injection, intranasal, oral, or via an 10 implanted device. Suitable implants include, for example, gel foam, wax, or microparticle-based implants.
Topical administration preferably includes agents or apparatus to facilitate skin delivery, such as solubilizing agents or directed delivery systems as are 15 known and being developed in the rapidly emerging technologies of skin delivery systems.
Therapeutically effective doses of CRF or its analogs in practicing this invention preferably are at least about O . 01 ,ugJkg in humans . For systemic 20 administration (e.g. subcutaneous and intravenous), more preferred doses are in the range of about 0.1 to about 50 ,ug/kg, and most preferred about 1 to about 30 ug/kg.
For local administration (e.g. intra-articular), the preferred dose is in a range of about 1 to about 100 25 ug/kg. Administration of CRF doses may be infused 510wly, such as subcutaneously or intradermally, or may be injected directly into an afflicted body part.
Patients treated will be under the care of a health care professional, such as a physician, who may 30 herself administer the therapeutic composition including CRF or may prescribe such for the patient s self administration (such as, for example, preloaded syringes). Systemic forms of administration are particularly preferred due to the frequent multiple 35 sites of episodic situations, or flares. Unfortunately, although treatments in accordance with the invention, as A~jjEl\~r-G 'U-'T
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further illustrated hereinafter, are shown efficacious, when treatment is stopped then efficacy also ceases. As with many other dif f erent types of therapies, the therapeutic method of this invention may ber combined 5 with other pharmaceuticals and other therapeutic approaches to the disease being treated.
Administration of CRF in accordance with this invention may potentially be continued for up to about three weeks, but side effects (e.g. Cushing's Syndrome) lO may tend to develop after prolonged intake. Thus, practice of this invention is primarily contemplated for treating acute, episodic flares, and CRF administration can be undertaken up to forty days after an episodic acute inf lammation occurs .
Although the peptides are generally water soluble as typically synthesized, they may be admini-stered in the form of pharmaceutically acceptable non-toxic salts, such as acid addition salts. Illustra-tive acid addition salts are hydrochloride, hydrobro-20 mide, sulfate, sulphate, acetate, citrate, benzoate, succinate, malate, ascorbate, tartrate, or the like. In addition to the f act that CRF may be administered in any pharmacologically acceptable carrier, depending upon the desired mode of administration it may be formulated 25 along with liquid carrier into liposomes, microcapsules, polymers, or wax-based and controlled release prepara-tions, or be formulated into tablet, pill, or capsule f orms .
A method f or treating a patient in accordance 30 with this invention involves patients suffering from one of the chronic inflammatory arthritides. By chronic inflammatory arthritides are meant to include rheumatoid arthritis, Reiters Syndrome, ankylosing spondylitis, psoriatic arthritis, and inf lammatory bowel ~isease .
35 Treatments are particularly useful for episodic acute inf lammations and provide anti-inf lammatory results in _~J~ rt.~ t~

WO95112416 PCrlUS94112621 2i 7~7 a do6e respon6ive manner. Experiments demonstrate that regardless of the time administered (e.g. up to about forty days after an episodic acute inflammation), practice of the invention reduces inf lammatio~ even in 5 well established disease; however, when treatment is discontinued, then the inf lammatory symptoms have been f ound to reoccur . Thus, the present invention is most likely a treatment rather than a cure.
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Therapeutic efficacy was demonstrated with a rat adjuvant arthritis model in which arthritis-susceptible male Lewis "LEW/N" rats had killed Myco-bacterium injected into the left-hind foot paw to induce arthritis .
With reference generally to Fig. 1, approxi-mately sixteen days post-induction of the disease animals ( i . e . animals treated with saline) had paws illustrated by paw 10; however, shortly after disease is induced, the mycobacterium in3ected paws 12 (and later, 20 as will be described, other paws) experience foot pad swelling. The foot pad swelling is a signal of inflammation. As is known, inflammation is manifested by redness, 6welling, heat and pain as a reaction of the body against injury or assault. Five days after 25 induction of the disease in the rats, CRF was administered subcutaneously twice a day at either a dose per administration of 50 ,ILg/kg or 100 ~g/kg. The twice a day administrations were continued for a period of 20 days. By approximately 16 days post-induction, the CRF
30 treated animals have comparatively little swelling or inf lammation.
Starting with the first day of administration (that is, day 5 after having injected the killed Myco-bacterium), the amount of swelling was determined by the WO 9S112416 PCTIUS9~/12621 57 ~I

use of calipers in mea6uring the thickness of left hind (injected) paw. This measurement served as a determination for the degree of "primary, " or acute, inflammation. Subsequently (usually about an ~dditional 5 10-12 days) the right hind paw also swells and becomes inf lamed . This represents a chronic inf lammatory response .
Turning to Fig. 2, the primarily inflamed left hind paw swelling data (measured through day 32) i6 10 shown for control rats, for rats receiving twice a day administrations of CRF at 50 ~Lg/kg body weight, and for rats receiving twice a day admini5trations of CRF at 100 ,~g/kg body weight. The vertical axis is measured in units where one unit is equivalent to 0 . 001 inches . As 15 is shown by the Fig. 2 data, administrations of CRF in accordance with the invention gave anti-inf lammatory re6ults and in a dose responsive manner. The three graphs of Fig. 2 all begin five days after the left hind paw was challenged wit1~ Mycobacterium. With twice a day 20 injection of 50 ,ug/kg CRF, there was reduced swelling relative to control. Results were even of greater signif icance with administrations of 100 ,ug/kg .
Turning to Fig. 3, data similar to that of Fig. 2 are represented, but the degree of foot pad 25 swelling being measured is that of the right hind paw and thus represents a chronic inflammatory response.
Administration of CRF at doses of either 50 ~g/kg or 100 g/kg were begun five days after challenge, as with Fig.
2, but the right hind paw has a swelling on-set later 30 than does the left hind paw illustrated by the Fig. 2 data. The right hind paw also experiences less swelling than the left hind paw. Of course, the right hind paw is not itself directly challenged as is the left hind paw. Nevertheless, as seen, beginning about day 11, the 35 right hind paw begins to swell; however, for animals receiving CRF in accordance with the invention, very WO g5/12416 Pcr~S94/12621 ~17~7 little swelling (for either the 50 ~g/kg body weight or the 100 ,ug/kg body weight) is experienced.
Turning to Fig. 4, the 2nimals as in Fig. 3 were also assessed for the extent of arthritis by using 5 a scoring system in which "0" indicated no arthritis and "4" represented severe arthritis. The arthritis scores were made by evaluating a combination of factors including the percent involvement of the foot pads plus the overall symptoms of the disease (which include lO swelling, redness, and disfigurement). The Fig. 4 data shows that both doses of CRF (50 ~Lg/kg and 100 I~g/kg) are active in reducing the arthritis scores, although the 100 ~g/kg dose appears to show a greater ef f ect .
The right hind paw of the animals were used for the Fig.
15 4 scoring.
With Fig. 5, conducted similarly to the just described Fig. 4, the two front paws were evaluated.
That is, Figs 4 and 5 both represent chronic, rather than acute, situations. However, the front paws used 20 for t~ a Fig. 5 data experienced an on-set of swelling and other symptoms even more delayed and less pronounced than for the right hind paws of Fig. 4. As is seen particularly with the Fig. 5 data, administrations of CRF in accordance with this invention are very effective 25 in treating for the clinical manifestations of chronic inf lammatory arthritis .
In the experiments summarized by the data of Figs. 2-5, treatments began five days after induction of the disease. Another set of experiments were undertaken 30 when the disease was induced as before, and the animals were then treated in accordance with the invention (at 100 Lg/kg doses administered twice daily subcutaneously) for a period of 20 days, except that the course of treatment began five days, 10 days, 15 days, 25 days, or 35 40 days after disease was induced. These experiments are summarized by the data of Figs. 6-8.

WO 95/12416 ~ PCr/US94112621 Turning to Fig. 6, panels A-E illustrate measurement6 taken of the left hind foot pad. Panel A
plots the foot pad thickness for the control rats and for rats who received treatment beginning on dzy 5 after 5 induction of the disease ( indicated by the open arrow) and ending on day 20 (indicated by the filled in, or closed, arrow). Thus, beginning promptly after treatment in accordance with the invention f ive days after induction of disea8e, footpad thickness was 10 considerably reduced with respect to the control, and the thickness reductions continued until treatment was discontinued, at which time swelling began and continued until by about day 60 there was substantially no difference between the previously treated footpad and 15 the control (never treated) footpad. Similarly, panel B illustrates data for the control and test rats with treatment beginning on day 10 and ending on day 3 0, panel C with treatment beginning on day lS and ending on day 35, panel D with treatment beginning on day 25 and 20 ending on day 45, and panel E with treatment beginning on day 40 and ending on day 60. These data demonstrate that when treating with CRF it profoundly reduced foot pad swelling, even in well established disease such as illustrated by panel E. Thus, panel E of Fig. 6 had 25 treatment begun forty days after induction of disease, yet promptly after treatment was begun, the treated footpad experienced reduced swelling Turning to Fig. 7, the data illustrated by panels A-E are similar to those described for Fig. 6, 30 but the foot pad swelling was measured in the animals' right hind foot pad. That is, as with Fig. 3, since the degree of f oot pad swelling being measured is that of the right hind paw (where the left hind paw is the site of mycobacterium injections and may represent acute 35 flares), the right hind paw may represent chronic inflammatory responses. Once again, these data , ... . ...... _ . , _ , _ _ _ .. _ _ .

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demonstrate that administering CRF in accordance with the invention profoundly reduces swelling, even in established disease, for chronic inflammatory conditions. r In experiments 6imilar to Figs. 6 and 7, but where the animals were assessed for the extent of arthritis by using a scoring system such as is described for Fig. 4, practice of the invention adds significantly against overall arthritic condition, although perhaps less than seen in reducing foot pad swelling. Turning to Fig. 8, in each of panels A-E animals receiving treatment are indicated for the times when treatment was ,~ ~n~rl by the open arrows. The times when treatments stopped are indicated by the f illed in, or closed, arrows.
Thus, with ref erence to panel A of Fig . 8, five days after an animal's left hind footpad had been challenged by the killed Mycobacterium, administrations of CRF in accordance with the invention were begun in the right hind footpad and were continued for a period of twenty days. During the course of treatment, the arthritis scores went down with respect to the control, but when the treatment was discontinued, these scores rose. Thus, practice of this invention is therapeutic as opposed to prophylactic. However, it is important to note, as illustrated by panel D of Fig. 8, that starting treatment in accordance with the invention as late as 25 days into the disease was still efficacious.
-It is to be understood that while the invention has been described above in conjunction with preferred specific ~rhQA;r~nts, the description and examples are intended to illustrate and not limit the WO 95/12416 " PCr/US9~112621 ~1 ~5~5~
~:cope of the invention, which is defined by the scope ofthe ~rr~ d claims.

Claims (13)

It is Claimed:

1. A method for treating a patient suffering from one of the chronic inflammatory arthritides, comprising:
administering at least over a plurality of days therapeutically effective doses of CRF to the patient.

2. The method as in claim 1 wherein the patient is suffering from rheumatoid arthritis.

3. The method as in claim 1 wherein each dose administered is at least about 0.01 µg/kg body weight.

4. The method as in claim 1 wherein the administration is by infusion or absorption.

5. The method as in claim 1 wherein the administration includes local injections each in a dose of from about 1 to about 100 µg/kg.

6. A method of treating a patient suffering from rheumatoid arthritis, comprising:
administering to the patient therapeutically effective doses of CRF in amounts over at least a plurality of days in a course of treatment effective to decrease inflammation of an afflicted body portion.

7. The method as in claim 6 wherein the administering reduces episodic acute inflammatory responses in the patient.

8. The method as in claim 6 wherein the administering is topical, intra-articular, intravenous, intrathecal, subcutaneous, injection, intranasal, oral, or via an implanted device.

9. The method as in claim 7 wherein the administering is undertaken within about forty days after an episodic acute inflammation.

10. The method as in claim 9 wherein the course of treatment is continued for not greater than about three continuous weeks.

11. The method as in claim 8 wherein each dose for systemic administration is in the range of about 0.1 to about 50 µg/kg and for local administration is in the range of from about 1 to about 100 µg/kg.

12. The method as in claim 1 or 6 wherein the CRF is in salt form.

13. The method as in claim 1 or 6 wherein the CRF is a CRF analog.