WO2007096744A1

WO2007096744A1 - Methods for the treatment of macular degeneration and related eye conditions

Info

Publication number: WO2007096744A1
Application number: PCT/IB2007/000413
Authority: WO
Inventors: Milton Lethan Pressler; William Sasiela
Original assignee: Pfizer Products Inc.
Priority date: 2006-02-21
Filing date: 2007-02-09
Publication date: 2007-08-30
Also published as: TW200744670A; AR059581A1; JP2007224032A

Abstract

Methods for the treatment of macular degeneration and related eye conditions

Description

METHODS FORTHE TREATMENT OF MACULAR DEGENERATION AND RELATED EYE CONDITIONS

1. FIELD OF THE INVENTION

The present invention is directed to the fields of ophthalmology and cell biology of vision. Specifically, the present invention regards the treatment, amelioration or prevention of age-related macular degeneration (ARMD), including nonexudative (Dry ARMD) and exudative (Wet ARMD) forms. The present invention encompasses novel compositions and methods to treat ARMD and related eye disorders. The method utilizes, or the composition comprises, unilamellar vesicles comprised of phospholipids.

2. BACKGROUND OF THE INVENTION 2.1 Age-Related Macular Degeneration

Age-related macular degeneration (ARMD) is one of the leading causes of severe visual loss in the developed world (Taylor et al., Br J Ophtalmol 85:261 -266, 2001; VanNewkirk βtal., Ophtalmol 107:1593- 1600, 2000). In the early stages of the disease, before visual loss occurs from choroidal neovascularization, there is progressive accumulation of lipids in Bruch's membrane (Pauleikhoff et al., PNAS USA 94:4647- 4652, 1990; HoIz et al., Amh Ophtalmol 112:402-406, 1994; Sheraidah etal., Ophtalmol 100:47-51, 1993; Spaide etal., Retina 19:141-147, 1999). Bruch's membrane lies at the critical juncture between the outer retina and its blood supply, the choriocapillaris. Progressive lipid deposition causes reduced hydraulic conductivity and macromolecular permeability in Bruch's membrane and thereby may impair retinal metabolism (Moore etal, Invenst Optalmol Vis Sd 36:1290-1297, 1995; Pauleikhoff etal., PNAS USA 94:4647-4652,1990; Starita etal., Exp Eye Res 62:565-572, 1996). After sufficient deposition of cholesterol and other lipids in Bruch's membrane, retinal pigmented epithelial cells (RPE) may respond by elaboration of angiogenic factors (e. g. VEGF, vFGF) that promote growth of new vessels from the choroid. Thus, reduced hydraulic conductivity is one possible explanation for RPE and retina ischemia. The other explanation is the decreased choroidal perfusion, which normally decreases with age and decreases more severely in patient with ARMD. Worsening levels of choroidal perfusion are accosiated with more severe levels ofARMD (Spraul et al., Invest Ophtalmol Vis Sd, 39(11):2201 -2202, 1998; Grunwald etal., Invest Ophtalmol Vis Sd, 46(3): 1033-1038, 2005; Ciulla etal., BrJ Ophtalmol. 86(2):209-213, 2002). Also, there is a histologic evidence of choroidal arteriosclerosis (Curcio et al., Invest Ophtalmol Vis Sd, 42:265, 2001).

Cholesterol transport may be important in the pathogenesis ofARMD because of lipid efflux from RPE into Bruch's membrane. Very much like intimal macrophages, RPE cells progressively accumulate lipid deposits throughout life; however, unlike vessel wall macrophages, the source of RPE lipid is thought to be retinal photoreceptor outer segments (POS) (Kennedy et al., Eye 9:262-274, 1995). Every day, each RPE cell phagocytoses and degrades more than one thousand POS via lysosomal enzymes. These POS are enriched in phospholipid and contain the photoreactive pigment, rhodopsin. Incompletely digested POS accumulate as lipofuscin in RPE. By age 80, approximately 20% of RPE cell volume is occupied by lipofuscin (Feeney- Bums et al., J invest Ophtalmol Vis Sci 25: 195-200, 1984).

Analysis of Bruch's membrane lipid reveals an age-related accumulation of phospholipid, triglyceride, cholesterol, and cholesterol ester (HoIz et al., 1994, supra; Curcio etal., J Invest Ophtalmol Vis Sd 42:265, 2001 ). The origin of these lipids also is thought to derive principally from POS rather than from the circulation (HoIz etal., 1994, supra; Spaide etal., 1999, supra). POS lipids are hypothesized to efflux from the RPE into Bruch's membrane. Although cholesterol ester deposition in Bruch's membrane suggests contribution from plasma lipids, biochemical analysis of these ethers suggests etherification of intracellular cholesterol by RPE cell derived ACAT (Curcio etal., ARVO Abstracts, 2002). While trafficking of lipids from the retina to RPE cells has been studied extensively, mechanisms of lipid efflux from RPE to Bruch's membrane are not well understood. Furthermore, from a pathogenic standpoint, regulation of lipid efflux into Bruch's membrane may be important in determining the rate of lipid-induced thickening that occurs in aging.

In atherosclerosis (AS), lipids accumulate in the extracellular matrix and within phagocytic cells, primarily macrophages. Mechanisms of lipid metabolism in AS have been investigated in detail. Similar investigations into lipid processing by RPE and subsequent lipid efflux into BM and the circulation have not been conducted with the same depth as those for AS. As a consequence, potential therapeutic approaches to ARMD are wonting.

Friedman (Friedman, Am J Ophtalmol 130(5):658-663, 2000) reviews the role of atherosclerosis in the pathogenesis of ARMD. Specifically, the review mentions targeting the angiogenesis pathway for treating the neovascular form of ARMD₁ such as the growth factor VEGF. It is noted that interfering with the upregulation or action of angiogenic agents may prove helpful for choroidal neovascularization, and, in alternative embodiments, statins may be useful for lowering the risk of ARMD.

U.S. Patent No. 5,824,685 regards amelioration of proliferative vitreoretinopathy or traction retinal detachment by contacting RPE cells with a retinoic acid receptor selected from ethyl-6- [2- (4, 4- dimethylthiochroman-6- yl) ethynylj nicotinate, 6- [2- (4, 4-dimethylchroman-6-yl) ethynyl] nicotinic acid, and p- [ (E)-2- (5,6, 7,8-tetrahydro-5, 5,8, 8-tetramethyl-2-naphthyl) propenyl] -benzoic acid.

WO 01/58494 is directed to treating or preventing an ocular disease, such as age-related macular degeneration, by contacting an ocular cell with an expression vector comprising a nucleic acid sequence encoding an inhibitor of angiogenesis and a neurotrophic agent. In specific embodiments, the inhibitor of angiogenesis and the neurotrophic agent are one and the same, such as pigment epithelium-derived factor (PEDF).

WO 02/13812 regards the use of an insulin-sensitizing agent, preferably peroxisome proliferator- activated receptor y (PPAR y) agonists, for the treatment of an inflammatory disease, such as an ophthalmic disease. WO 00/52479 addresses diagnosing, treating, and preventing drusen-associated disorders (any disorder which involves drusen formation), including ARMD. In specific embodiments, there are methods related to providing an effective amount of an agent that inhibits immune cell proliferation or differentiation, such as antagonists of the cytokine, tumor necrosis factor (TNF)-alpha.

WO 2004/098506 and WO 2004/0266663 describe the treatment of age-related macular degeneration using regulation of pathogenic mechanisms similar to atherosclerosis. In specific embodiments, reverse cholesterol transport components, such as transporters and HDL fractions, are utilized as diagnostic and therapeutic targets for age-related macular degeneration.

Jorge G. Arroyo in the "Age-related macular degeneration-l and II," UpToDate (on-line service) (last modified September 19, 2005), provides background information on age-related macular degeneration, including epidemiology, etiology/risk factors, clinical presentation, diagnosis, treatment and prevention.

Duncan et al. (Duncan et al., 2005) describes that the findings in LDL receptor deficient mice may provide insight into the mechanism of early ARMD.

Rudolf et al. (Rudolf et al., 2005) describes that LDL receptor deficient mice exhibit an accumulation of lipid particles in Bruch's membrane which is further increased after fat intake.

2.2 Liposome-Mediated Cholesterol Transport

Several human conditions are characterized by distinctive lipid compositions of tissues, cells, membranes, and extracellular regions or structures. One example, is an ARMD characterised by progressive accumulation of cholesterol and other lipids in Bruch's membrane, as discussed above. The other example is atherosclerosis, in which cholesterol (unesterified, esterified, and oxidized forms) and other lipids accumulate in cells and in extracellular spaces of the arterial wall and elsewhere. These lipids have potentially harmful biologic effects, for example, as modulators changing cellular functions, including gene expression, and as deposits narrowing the vessel lumen, obstructing the flow of blood. Removal of these lipids would provide numerous substantial benefits. Moreover, cells, membranes, tissues, and extracellular structures will benefit in general from compositional alterations that include increasing resistance to oxidation and oxidative damage, such as by increasing the content and types of anti-oxidants, removing oxidized material, and increasing the content of material that is resistant to oxidation. In aging, cells have been shown to accumulate sphingomyelin and cholesterol, which alter cellular functions. These functions can be restored in vitro by removal of these lipids and replacement with phospholipid from liposomes. A major obstacle to performing similar lipid alterations in vivo has been disposition of the lipids mobilized from tissues, cells, extracellular areas, and membranes. Natural (e.g., high-density lipoproteins) and synthetic (e.g., small liposomes) particles that could mobilize peripheral tissue lipids have a substantial disadvantage: they deliver their lipids to the liver in a manner that disturbs hepatic cholesterol homeostasis, resulting in elevations in plasma concentrations of harmful lipoproteins, such as low-density lipoprotein (LDL), a major atherogenic lipoprotein. There exists a need for a better method to manipulate the lipid content and composition of peripheral tissues, cells, membranes, including Batch's membranes and extracellular regions in vivo.

Thus, there is a need for a new approach for the treatment, amelioration or prevention of age- related macular degeneration by reducing the size and lipid content of drusens and other pathological lesions of the retina and ocular tissue, such as the Bruch's membrane.

3. SUMMARY OF THE INVENTION

The invention encompasses a unique approach for the prevention or treatment of age-related macular degeneration or a related disorder in a subject using unilamellar liposomes comprising phospholipids.

The present invention provides a pharmaceutical composition comprised of unilamellar vesicles. In one embodiment, the present invention provides a pharmaceutical composition comprised of liposomes consisting essentially of phospholipids which are substantially free of sterol, and a pharmaceutically acceptable carrier. The liposome composition is selected from the group consisting of unilamellar liposomes and multilamellar liposomes and the liposomes have an average diameter of about 50 nm to about 200 nm. The liposomes have average diameters larger than about 50 nm, average diameters larger than about 100 nm, and average diameters larger than about 150 nm in different variants. In a specific embodiment, liposomes have mean diameters of about 125 nm.

The invention encompasses prevention or treatment of age-related macular degeneration with large unilamellar liposomes containing any suitable phospholipid including but not limited to phosphatidyl choline, phosphatidyl glycerol, palmitoyl-oleoyl phosphatidyl choline, combinations thereof, and derivatives thereof. In one embodiment, phospholipid is 1-palmitoyl-2-oleyl-sn-glycero-3-phosphocholine (POPC).

The methods of the invention comprise administering to a subject in need thereof a therapeutically effective amount of unilamellar vesicles comprised of phospholipids or a pharmaceutically acceptable salt thereof. In one embodiment, unilamellar vesicles comprised of phospholipids that are substantially free of sterol for the treatment of age-related macular degeneration. The therapeutically effective amounts of a liposome composition are in the range of about 10 mg to about 300 mg of phospholipid per kg body weight per dose.

The methods for preventing or treating age-related macular degeneration employ the pharmaceutical compositions of the present invention. The compositions are administered to a subject having age-related macular degeneration, often, the compositions will be serially administered over a period of time. Generally, the compositions will be administered parenterally. The methods may be employed therapeutically or prophylactically.

Methods, compositions and dosage regimens are provided herein, and are believed to encompass safe, effective and non-surgical treatments, without being limited by theory, that rapidly promote cholesterol efflux and mobilization from lipidic plaques in the retina or Bruch's membrane (e.g. drusens), which thereby confer benefit in terms of improvement of visual acuity, prevention of loss of visual acuity, or improvement or prevention of macular degeneration that leads to impaired visual acuity. The mechanism of action encompasses improved blood flow or perfusion of the retina or choroid plexus that directly or indirectly confers improvement in visual acuity, or prevention of loss of visual acuity, or confers amelioration of lesions that promote neovascularization of the retina that reduce visual acuity.

The objects and features of the present invention, other than those specifically set forth above, will become apparent in the detailed description of the invention set forth below.

4. DETAILED DESCRIPTION OF THE INVENTION

4.1 Definitions

As used herein, the following terms shall have the following meaning:

As used herein in the specification, "a" or "an" may mean one or more. As used herein in the claim(s), when used in conjunction with the word "comprising", the words "a" or "an" may mean one or more than one. As used herein "another" may mean at least a second or more.

The term "age-related macular degeneration" as used herein refers to macular degeneration, both wet and dry forms, early or late stage, in an individual over the age of about 50. In one specific embodiment, it is associated with destruction and loss of the photoreceptors in the macula region of the retina resulting in decreased central vision and, in advanced cases, legal blindness.

The term "Bruch's membrane" as used herein refers to a five-layered structure separating the choriocapillaris from the retinal pigmented epithelium (RPE).

The term "increase lipid efflux" or "increasing lipid efflux" as used herein refers to an increased level and/or rate of lipid efflux, promoting lipid efflux, enhancing lipid efflux, facilitating lipid efflux, upregulating lipid efflux, improving lipid efflux, and/or augmenting lipid efflux. In a specific embodiment, the efflux comprises efflux of phospholipid, triglyceride, cholesterol, and/or cholesterol ester.

The term "macula" as used herein refers to the light-sensing cells or photoreceptors of the central region of the retina.

The term "macular degeneration" as used herein refers to deterioration of the central portion of the retina, the macula.

The term "subject" refers to an animal such as a mammal, including but not limited to a primate (e.g., a human), a dog, a cat, a rabbit, a rat, a mouse and the like. In specific embodiments, the subject is a human.

The term "therapeutically effective amount" refers to that amount of an active ingredient sufficient to improve one or more of the symptoms of the condition or disorder being treated as compared to those symptoms that occur without treatment. The improvement may be temporary or permanent.

The term "prophylactically effective amount" refers to that amount of an active ingredient sufficient to result in the prevention, onset or recurrence of one or more symptoms of the condition or disorder.

The term "pharmaceutical formulation" or "pharmaceutical composition" refers to a composition comprising either an active ingredient and a suitable diluent, carrier, vehicle, or excipients suitable for administration to a subject. The pharmaceutical formulation or composition comprises unilamellar liposomes. The terms "composition" and 'formulation" are used interchangeably herein. This term includes, but is not limited to oral, parenteral, intraocular, mucosal and topical compositions as described below.

The term "pharmaceutically acceptable composition" or "pharmaceutically acceptable formulation" refers to a product comprising an active ingredient and a pharmaceutically acceptable carrier, diluent or excipient. By "pharmaceutically acceptable" it is meant the carrier, diluent or excipient must be compatible with the other ingredient of the formulation and not deleterious to the recipient thereof.

The term "pharmaceutically acceptable salts" is meant to include salts of active compounds which are prepared with relatively nontoxic acids or bases. Acid addition salts can be obtained by contacting the neutral form of such compounds with a sufficient amount of the desired acid, either neat or in a suitable inert solvent. Examples of pharmaceutically acceptable salts include those derived from inorganic acids like hydrochloric, hydrobnomic, nitric, carbonic, monohydrogencarbonic, phosphoric, monohydrogenphosphoric, dihydrogenphosphoric, sulfuric, monohydrogensulfuric, hydriodic, or phosphorous acids and the like, as well as the salts derived from relatively nontoxic organic acids like acetic, propionic, isobutyric, maleic, malonic, benzoic, succinic, suberic, fumaric, mandelic, phthalic, benzenesulfonic, p-tolylsulfonic, citric, tartaric, methanesulfonic, and the like. Also included are salts of amino acids such as arginate and the like, and salts of organic acids like glucuronic or galactunoric acids and the like (see, for example, Berge et al., 1977 J. Pharm. ScL 66:1-19). Suitable bases capable of forming salts with L-NMMA include, for example, inorganic bases such as sodium hydroxide, ammonium hydroxide, potassium hydroxide the like; and organic bases such as mono-, di- and tri-alkyl amines (e.g., triethyl amine, diisopropyl amine, methyl amine, dimethyl amine and the like ) and optionally substituted ethanolamines (e.g., ethanolamine, diethanolamine and the like). It is within the knowledge of those skill in the art to determine which phospholipids could create a pharmaceutically acceptable salt.

The term "pharmaceutically acceptable carrier" refers to, for example, normal saline, glucose, trehalose, sucrose, sterile water, buffered water, 0.4% saline, and 0.3% glycine. The term "pharmaceutically acceptable buffer" includes, but is not limited to, citrate, acetate, phosphate, tris(hydroxymethyl)- aminomethane or THAM (tromethamine). The compositions can contain pharmaceutically acceptable excipients or auxiliary substances as required to approximate physiological conditions, such as pH adjusting and buffering agents, and tonicity adjusting agents, for example, sodium acetate, sodium lactate, sodium chloride, potassium chloride, calcium chloride and the like. Injectable pharmaceutical compositions often include an antimicrobial component, especially for multi-dose dosage forms.

The terms "liposome", "vesicle" and "liposome vesicle" refer to structures having lipid-containing membranes enclosing aqueous interior. The structures may have one or more lipid membranes, generally the liposomes have only one membrane. Such single layered liposomes are referred to herein as "unilamellar liposomes". Multilayered liposomes are referred to as "multilamellar liposomes".

The term "drug" refers to a synthetic compound suitable for therapeutic use without associated bound carriers, adjuvants, activators or co-factors. It does not include apolipoproteins, lecithin cholesterol acyltransferase or albumin.

The term "dose" refers to a quantity of a drug or other remedy to be taken or applied all at one time or in fractional amounts within a given period of time.

The term "dosing regimen" refers to a dose schedule.

The terms "treat" , "treating" or "treatmenf refer to alleviating, reducing, abrogating, or otherwise modulating a disease, disorder and/or symptoms thereof, that is a therapeutic effect on an existing condition.

The terms "prevent" , "preventing" or "prevention" refer to barring, or reducing the risk of, a subject from acquiring a disease, disorder and/or symptoms thereof.

The term "about" refers to a relative term denoting an approximation of plus or minus 10% of the nominal value it refers to, preferably plus or minus 5%, most preferably plus or minus 2%. For the field of this disclosure, this level of approximation is appropriate unless the value is specifically stated to require a tighter range.

The term "label" refers to a display of written, printed or graphic matter upon the immediate container of an article, for example, the written material displayed on a vial containing a pharmaceutically active agent.

The term "labeling" refers to all labels and other written, printed or graphic matter upon any article or any of its containers or wrappers or accompanying such article, for example, a package insert, instructional videotapes or instructional DVDs accompanying or associated with a container of a pharmaceutically active agent.

The term "/kg" refers to a subject's body weight.

4.2. Methods of the invention

In one aspect, the present invention provides methods for treating age-related macular degeneration (ARMD) by administering to a subject in need thereof a therapeutically effective amount of unilamellar vesicles comprised of phospholipids or a pharmaceutically acceptable salt thereof.

In one embodiment, the present invention provides methods for treating ARMD by administering to a subject in need thereof a therapeutically effective amount of unilamellar vesicles consisting essentially of phospholids which are substantially free of sterol, and the vesicles are not bound to a drug. Unilamellar vesicles of the present invention have an average diameter of about 50 nm to about 200 nm. In one embodiment, liposomes have average diameters larger than 50 nm. In another embodiment, liposomes have average diameters larger than 100 nm. In yet another embodiment, liposomes have average diameters larger than 150 nm. In a specific embodiment, liposomes have average diameters of about 125 nm.

In one embodiment, the methods of the invention include administering an effective amount of "empty liposomes" to treat ARMD. "Empty" is a standard terminology to indicate an absence of an encapsulated drug within a liposome, or that no encapsulated drug is essential for one or more functions of a liposome and that a liposome interior may contain non-drug materials such as water and other inert molecules.

The subject can be any mammalian subject that is experiencing ARMD or related condition. In one embodiment, the animal is a human. In other embodiments, non-human primates, dogs, cats, rodents, horses, cows and the like may be treated by the methods of the present invention.

The ARMD can be any ARMD known to those of skill in the art. In certain embodiments, the ARMD is a nonexudative ARMD (dry form). In certain embodiments, the ARMD is an exudative ARMD (wet form). In a specific embodiment, the subject is a human. The subject can be of any age suitable for the administration of large unilamellar liposomes according to guidelines known to practitioners of skill in the art.

In the methods of the present invention, by "treating ARMD" it is meant performing a therapeutic intervention that results in reducing the cholesterol content of at least one drusen in the Bruch's membrane of the retina of an eye or prophylactically inhibiting or preventing the formation or expansion of a drusen. By using the methods of the invention, the volume of a cholesterol content in the Bruch's membrane is reduced. In one embodiment, the cholesterol content is reduced by at least 10-30%. In another embodiment, the cholesterol content is reduced by 30-50%. In yet another embodiment, the cholesterol content is reduced by 50-75%. The volume of a drusen is also reduced. In one embodiment, the volume of a drusen is reduced by at least 10-30%. In another embodiment, the volume of a drusen is reduced by 30-50%. In yet another embodiment, the volume of a drusen is reduced by 50-75%.

In the methods of the present invention, the liposomes are in the liquid-crystalline state at 37⁰C, at 35⁰C or at 32⁰C. Liposomes in the liquid-crystalline state typically accept cholesterol more efficiently than liposome in a gel state. As patients usually have a core temperature of about 37⁰C, liposomes composed of lipids that are liquid-crystalline at 37⁰C are generally in a liquid-crystalline state during the treatment and, therefore, optimize removal of cholesterol from drusens in Bruch's membranes.

4.3 Pharmaceutical Compositions of the Invention

The present invention provides pharmaceutical compositions comprised of unilamellar vesicles and a pharmaceutically acceptable carrier. In one embodiment of the invention, the pharmaceutical composition consists essentially of unilamellar liposomes which are substantially free of sterol and are not bound to a drug. In one aspect, unilamellar vesicles of the present invention have an average diameter of about 50 nm to about 200 nm. In another aspect, unilamellar vesicles of the present invention have an average diameter of about 100 nm to about 200 nm. In one embodiment, liposomes have average diameters larger than 50 nm. In another embodiment, liposomes have average diameters larger than 100 nm. In yet another embodiment, liposomes have average diameters larger than 150 nm. In a specific embodiment, liposomes have average diameters of about 125 nm.

The pharmaceutical compositions comprise pharmaceutically acceptable excipients as required to approximate physiological conditions, such as pH adjusting agents, buffering agents, and tonicity adjusting agents (e.g., sodium acetate, sodium lactate, sodium chloride, potassium chloride, and calcium chloride). They may also comprise osmotically active cryoprotectants like mannitol or sucrose. Antibacterial agents (e.g., phenol, benzalkonium chloride or benzethonium chloride) can be added to maintain sterility of a product, especially to pharmaceutical formulations intended for multi-dose parenteral use. Suspending, stabilizing and/or dispersing agents can also be used in the compositions of the invention.

The pharmaceutical formulation can be in a variety of forms suitable for any route of administration which include, but are not limited to parenteral, intraocular, subcutaneous, oral, transdermal, transmucosal and rectal administration.

In a preferred embodiment, the composition is formulated in accordance with routine procedures as a pharmaceutical composition adapted for parenteral administration.

Parenteral administration refers to any route of administration that is not through the alimentary canal, including, but not limited to, injectable administration {i.e., intravenous, intraarterial, intramuscular, intradermal, intraocular, and the like as described herein) (see generally, Remington's Pharmaceutical Sciences, 18^th Edition, Gennaro et al., eds., Mack Printing Company, Easton, Pennsylvania, 1990).

The pharmaceutical formulation of the present invention can be in a form suitable for ocular route of administration, which includes, but are not limited to an intraocular (intracamera!) injection, a subconjunctival, sub-Tenon's, retrobulbar, intravital injection and a topical application. In a specific embodiment, the pharmaceutical formulation is injected directly into the eye or the space surrounding the orbit of the eye. The injectable pharmaceutical formulation can be a pharmaceutically appropriate formulation for administration directly into the eye including aqueous and vitreous humors.

Injectable pharmaceutical formulations can be sterile suspensions, solutions or emulsions in aqueous or oily vehicles. The formulations for injection can be presented in unit dosage form, e.g., in ampoules or in multidose containers, and can comprise added preservatives. Buffers suitable for parenteral pharmaceutical formulations are phosphate, citrate and acetate, and may contain stabilizers or cryopreservatives (e.g., sucrose, mannitol).

Suitable vehicles that can be used to provide parenteral dosage forms of the invention are well known to those skilled in the art. Examples include, but are not limited to: Water for Injection USP; aqueous vehicles such as, but not limited to, Sodium Chloride Injection, Ringer's Injection, Dextrose Injection, Dextrose and Sodium Chloride Injection, and Lactated Ringer's Injection; water-miscible vehicles such as, but not limited to, ethyl alcohol, polyethylene glycol, and polypropylene glycol; and non-aqueous vehicles such as, but not limited to, corn oil, cottonseed oil, peanut oil, sesame oil, ethyl oleate, isopropyl myristate, and benzyl benzoate. Compounds that increase the solubility of one or more of the active ingredients disclosed herein can also be incorporated into the parenteral dosage forms of the invention.

The pharmaceutical formulations can be formulated for a single, one-time use or can be formulated in multiple doses. In certain embodiments, the pharmaceutical formulation can be lyophilized in sterile bottles or in sterile pre-filled syringes or sterile pre-filled bags which can be frozen or refrigerated.

4.3.1 Use of liposomes

In one aspect, the present invention provides compositions and methods for the treatment of ARMD (age-related macular degeneration), its various forms (e.g., wet, dry; early, late) or related conditions by administering a pharmaceutical composition comprised of unilamellar liposomes. In one embodiment, the pharmaceutical composition of the invention consists essentially of unilamellar liposomes which are substantially free of sterol and are not bound to a drug, and a pharmaceutically acceptable carrier. In one aspect, unilamellar vesicles of the present invention have an average diameter of about 50 nm to about 200 nm. In some instances, multilamellar liposomes may be employed in the compositions of the present invention, either exclusively or in addition to unilamellar liposomes. The liposomes have an average diameter of about 50 nm to about 200 nm, typically about 100 nm to about 200 nm. As used herein, liposomes may or may not be in the form of a pharmaceutical composition.

Liposomes utilized by the pharmaceutical compositions of the present invention may be obtained by any method known to those skilled in the art, such as described in, e.g., U.S. Patent Nos.4,186,183, 4,217,344, 4,261,975, 4,485,054, 4,774,085, 4,946,787, 6,139,871, US published application US 2005/0260256 published November 24, 2005, PCT publication No. WO91 /17424, Deamer and Bangham (1976), Fraley et Qi., 1979, Hope θtal., 1985, Mayer et al., 1986, and Williams θtal., 1988, each of which is incorporated herein by reference. Suitable methods include, but not limited to, sonication, extrusion, high pressure/homogenization, microfluidization, detergent dialysis, calcium-induced fusion of small liposome vesicles and ether-infused methods.

Generally, the liposomes are most conveniently generated by sonication and extrusion procedures. Sonication is generally performed with a tip sonifier, such as a Branson tip sonifier, in an ice bath. Typically, the suspension is subjected to several sonication cycles. Extrusion may be carried our by biomembrane extruders, such as the Lipex Biomembrane Extruder. Defined pore size in the extrusion filters may generate unilamellar liposome vesicles of specific sizes. Liposomes may also be formed by extrusion through an asymmetric ceramic filter, such as a Ceraflow Microfilter, commercially available from the Norton Company, Worcester, MA.

The size of the liposomal vesicles may be determined by quasi-electric light scattering (QELS) as described in Bloomfield, Ann Rev Biophys Bioeng, 10:421-450 (1981), incorporated herein by reference. Average liposome diameter may be reduced by sonication of formed liposomes. Intermittent sonication cycles may be alternated with QELS assessment to guide efficient liposome synthesis.

In order to obtain multilamellar liposome vesicles, a chloroform solution of a lipid is vortexed and the solvent is removed under a steady stream of nitrogen. The sample is dried under a high vacuum. The resulting dry lipid film is rehydrated in 150 mM NaCI and 20 mM [4-(2-hydroethyl)]-piperazine-ethanesulfonic acid (Hepes, pH 7.4).

The lipid can be any suitable lipid known to those of skill in the art. Non-phosphorus containing lipids can be used, including stearylamine, dodecylamine, acetyl palmitate, (1 ,3)-D-mannosyl- (1,3)diglyceride, aminophenylglycoside, 3-cholesteryl- 6'-(glycosylthio)hexyl ether glycolipids, N-(2,3-di(9-(Z)- octadecenyloxy))-prop-1-yl-N,N,N-trimethylammonium chloride and fatty acid amides. Additional lipids suitable for use in the liposomes of the present invention are well known to those skilled in the art and cited in a variety of sources, e.g., McCutcheon's Detergents and Emulsifiers and McCutcheon's Functional Materials. Allured Publishing Co., Ridgewood, N.J., both of which are incorporated herein by reference.

In one embodiment, the lipid is a phospholipid. The phospholipid can be obtained from any source known to those of skill in the art. For example, the phospholipid can be obtained from commercial sources, natural sources or by synthetic or semi-synthetic means known to those of skill in the art (see, e.g., Mel'nichuk etal., UkrBiokhim Zh 59(6):75-7 (1987); Mel'nichuk etal., UkrBiokhim Zh 59(5):66-70 (1987); Ramesh etal, J. Am. Oil Chem. Soc. 56(5):585-7 (1979); Patel and Sparrow, J Chromatogr 150(2):542-7 (1978); Kaduce βtal., J Lipid Res 24(10): 1398-403 (1983); Schlueter etal., Org Lett 5(3):255-7 (2003); Tsuji etal., Nippon Yakurigakυ Zasshi 120(1 ):67P-69P (2002)).

The phospholipid can be any phospholipid known to those of skill in the art. For example, the phospholipid can be a small alkyl chain phospholipid, phosphatidylcholine, egg phosphatidylcholine, soybean phosphatidylcholine, dipalmitoylphosphatidylcholine, soy phosphatidylglycerol, egg phosphatidylglycerol, distearoylphosphatidylglycerol, dimyristoylphosphatidylcholine, distearoylphosphatidylcholine, dilaurylphosphatidylcholine,

1 -myristoyl-2-palmitoylphosphatidylcholine, 1 -palmitoyl-2-myristoylphosphatidylcholine, 1 -palmitoyl-2- stearoylphosphatidylcholine, 1 -stearoyl-2-palmitoylphosphatidylcholine, dioleoylphosphatidylcholine, 1 - palmitoyl-2-oleoylphosphatidylcholine, 1-oleoyl-2-palmitylphosphatidylcholine, dioleoylphosphatidylethanolamine, dilauroylphosphatidylglycerol, phosphatidylserine, phosphatidyiethanolamine, phosphatidylinositol, phosphatidylglycerol, diphosphatidylglycerol, dimyristoylphosphatidylglycerol, dipalmitoylphosphatidylglycerol, distearoylphosphatidylglycerol, dioleoylphosphatidylglycerol, phosphatidic acid, dimyristoylphosphatidic acid, dipalmitoylphosphatidic acid, dimyristoylphosphatidylethanolamine, dipalmitoylphosphatidylethanolamine, dimyristoylphosphatidylserine, dipalmitoylphosphatidylserine, brain phosphatidylserine, sphingomyelin, sphingolipids, brain sphingomyelin, dipalmitoylsphingomyelin, distearoylsphingomyelin, galactocerebroside, gangliosides, cerebrosides, phosphatidylglycerol, phosphatidic acid, lysolecithin, lysophosphatidylethanolamine, cephalin, cardiolipin, dicetylphosphate, distearoyl-phosphatidylethanolamine. The phospholipid can also be a derivative or analogue of any of the above phospholipids. The preferedd phospholipid is POPC.

In one embodiment, the liposomes of the present invention are composed of one phospholipid.

In another embodiment, liposomes are composed of more than one phospholipid.

Generally, it is desirable that the liposomes be composed of lipids that are liquid-crystalline at 37⁰C, at 35⁰C and at 32⁰C. Liposomes in the liquid-crystalline state typically accept cholesterol more efficiently than liposome in a gel state. As patients usually have a core temperature of about 37⁰C, liposomes composed of lipids that are liquid-crystalline at 37⁰C are generally in a liquid-crystalline state during the treatment and, therefore, optimize removal of cholesterol from drusens in Bruch's membranes.

The pharmaceutical compositions of the present invention also comprise a pharmaceutically acceptable earner. Many pharmaceutically acceptable carriers may be employed in the compositions of the present invention. Suitable carriers include, but are not limited to, glucose, trehalose, sucrose, sterile water, buffered water, 0.4% saline, and 0.3% glycine and glycoproteins for enhanced stability, such as albumin, lipoprotein, globulin, etc. The pharmaceutically acceptable buffer includes, but is not limited to, citrate, acetate, phosphate, tris(hydroxymethyl)-aminomethane or THAM (tromethamine). The compositions can contain pharmaceutically acceptable excipients or auxiliary substances as required to approximate physiological conditions, such as pH adjusting and buffering agents, and tonicity adjusting agents, for example, sodium acetate, sodium lactate, sodium chloride, potassium chloride, calcium chloride and the like. Injectable pharmaceutical compositions often include an antimicrobial component, especially for multi-dose dosage forms.

These compositions may be sterilized by conventional, well-known sterilization techniques. The resulting aqueous solution may be packaged for further use or filtered under aseptic conditions and lyophilized, the lyophilized preparation being combined with a sterile aqueous solution prior to administration.

The concentration of liposomes in the carrier may vary. In one embodiment, the liposomes' concentration is about 20-300 mg/ml. In another embodiment, it is about 50-200 mg/ml. In yet another embodiment, the concentration is about 200 mg/ml. Persons of skill in the art may vary these concentrations to optimize treatment with different liposomal components or for particular patients.

The pharmaceutical compositions of the present invention can be in a variety of forms suitable for any route of administration which include, but are not limited to parenteral, intraocular, subcutaneous, oral, transdermal, transmucosal and rectal administration.

In one embodiment, the composition is formulated in accordance with routine procedures as a pharmaceutical composition adapted for parental administration.

Parenteral administration refers to any route of administration that is not through the alimentary canal, including, but not limited to, injectable administration (i.e., intravenous, intraarterial, intramuscular, intradermal, intraocular, and the like as described herein) (see generally, Remington's Pharmaceutical Sciences, 18^th Edition, Gennaro etal., eds., Mack Printing Company, Easton, Pennsylvania, 1990).

The pharmaceutical formulation of the present invention can be in a form suitable for an ocular route of administration, which includes, but is not limited to an intravitreal, intraocular (intracameral), subconjunctival, sub-Tenon's, retrobulbar injection and a topical application. In one embodiment, the pharmaceutical formulation is administered as an intravitreal injection. The injectable pharmaceutical formulation of the present invention is ophthalmically acceptable, i.e., it is appropriate for administration directly into the eye including aqueous and vitreous humors.

Injectable pharmaceutical formulations can be sterile suspensions, solutions or emulsions in aqueous or oily vehicles. The formulations for injection can be presented in unit dosage form, e.g., in ampoules or in multidose containers, and can comprise added preservatives. In one embodiment, the buffers for parenteral pharmaceutical formulations are phosphate, citrate and acetate, and may contain stabilizers or cryopreservatives (e.g., sucrose, mannitol, trehalose).

The doses of liposomes may vary depending on the clinical condition of a patient receiving the treatment and the route of administration. In one embodiment of the invention, the intravenous dose is about 10-300 mg of liposomes/kg body weight. In another embodiment, the intravenous dose is about 25- 200 mg of liposomes/kg body weight. In another embodiment, the intravenous dose is about 50-150 mg of liposomes/kg body weight. In yet another embodiment, the intravenous dose is about 100-150 mg of liposomes/kg body weight. Thus, an average 70 kg person is treated with about 4-8 g of intravenous liposomes per treatment. For intraocular doses, the dose is greatly reduced because of the limited volume of the orbit and its structures. In one embodiment, the intraocular dose is about 0.4-8 mg of liposomes/kg of body weight. In another embodiment, the intraocular dose is about 0.5-4 mg of liposomes/kg of body weight. In yet another embodiment, the intraocular dose is about 1-2 mg of liposomes/kg of body weight. The dose is ussually constant over the course of treatment, also it may vary according to clinical outcome of a patient.

The pharmaceutical formulations can be formulated for a single, one-time use or can be formulated in multiple doses. The components of the combination therapy can be in the same or different pharmaceutical formulations and can be administered simultaneously or sequentially. In certain embodiments, the pharmaceutical formulation can be lyophilized in sterile bottles or in sterile pre-filled syringes or sterile pre-filled bags which can be frozen or refrigerated. The formulation can also be lyophilized and reconstituted with a suitable vehicle.

4.3.2 Pharmaceutical compositions of ETC-588

The pharmaceutical composition consisting essentially of unilamellar vesicles of

1-palmitoyl-2-oleoyl-sπ-glycero-3-phosphocholine (POPC), referred to as ETC-588, is suitable for treatment of age-related macular degeneration or related conditions.

In one aspect, the pharmaceutical formulation consists essentially of liposomes, consisting of POPC, having an average diameter of about 100 nm or a mean diameter of 125 ± 30 nm, suspended in a phosphate-buffered saline and stored at 2-8⁰C.

In certain embodiments, the pharmaceutical formulation comprises a buffer in an amount sufficient to make a pharmaceutically suitable formulation of ETC-588. In some embodiments, the pharmaceutical formulation comprises a phosphate buffer. In particular embodiments, the phosphate concentration is about 10 mM to about 30 mM. In specific embodiments, the phosphate concentration is about 15 mM to about 25 mM. In a specific embodiment, the phosphate concentration is about 20 mM.

In certain embodiments, the pharmaceutical formulation comprises a saline in an amount sufficient to make a pharmaceutically suitable formulation of ETC-588. In some embodiments, the pharmaceutical formulation comprises sodium chloride. In particular embodiments, the sodium chloride concentration is about 80 mM to about 200 mM. In specific embodiments, sodium chloride concentration is about 110 mM to about 150 mM. In a specific embodiment, sodium chloride concentration is about 130 mM.

In certain embodiments, an appropriate buffer is added to adjust the pH of the pharmaceutical formulation to a range suitable for administration to a subject. In certain embodiments, the pharmaceutical formulation has a pH of about 6.8 to about 7.8. In some embodiments, the pharmaceutical formulation has a pH of about 7.0 to about 7.8. In other embodiments, the pharmaceutical formulation has a pH of about 7.2 to about 7.6. In a specific embodiment, the pharmaceutical formulation has a pH of about 7.4.

In another embodiment, the pharmaceutical formulations can be provided in a powder form or lyophilized form for reconstitution before use with a suitable vehicle, including but not limited to sterile pyrogen free water, phosphate buffered saline, saline or dextrose. To this end, the ETC-588 can be lyophilized. In another embodiment, the pharmaceutical formulations can be supplied in unit dosage forms and reconstituted prior to use.

Targeting of ocular tissues may be accomplished in any one of a variety of ways. Injection into the aqueous or vitreous humor of the eye is one means. Directly injecting the

ETC-588 into the proximity of the RPE or Bruch's membrane provides targeting of the complex with some forms ofARMD. In one embodiment, the complex is administered via intra-ocular sustained delivery (such as Vitrasert® or Envision® by Bausch and Lomb). In another embodiment, the compound is delivered by posterior suborbital injection.

In certain embodiments, the pharmaceutical formulation of the ETC-588 is a unit dose package. As is known to those of skill in the art, a unit dose package provides delivery of a single dose of a drug to a subject. The compositions and methods of the invention provide a unit dose package of a pharmaceutical formulation comprising, for example, 8 g of liposomes per package. For example, 8 g of liposomes is an amount that administers 100 mg of liposomes/kg body weight to a 70 kg subject. The unit can be, for example, a sterile single use vial, a sterile pre-filled syringe, a sterile pre-filled bag (i.e., piggybacks) and the like.

In other embodiments, the pharmaceutical formulation is a unit-of-use package. As is known to those of skill in the art, a unit-of-use package is a convenient, prescription size, patient ready unit labeled for direct distribution by health care providers. A unit-of-use package contains a pharmaceutical formulation in an amount necessary for a typical treatment interval and duration for a given indication. The compositions and methods of the invention provide for a unit-of-use package of a pharmaceutical formulation comprising the ETC-588 in an amount sufficient to treat an average sized adult male or female with, for example, 75 mg of liposomes/kg body weight once weekly for 5 weeks. Thus, a unit-of-use package may comprise five doses of the ETC-588 (available in a vial or pre-filled syringes). In one embodiment, the unit-of-use package comprises a pharmaceutical formulation comprising the ETC-588 in an amount sufficient to treat an average sized adult male or female with a dose of 75 mg of liposomes/kg, 100 mg of liposomes/kg or 150 mg of liposomes/kg body weight once weekly for 5 weeks. It will be apparent to those of skill in the art that the doses described herein are based on the subject's body weight.

The pharmaceutical formulations comprising the ETC-588 must be of a suitable pH, osmolality, tonicity, purity and sterility to allow safe administration to a subject. 4.3.3 Use of ETC-588 for Treating Age-Related Macular Degeneration (ARMD)

The doses of ETC-588 encompassed by the invention are described herein. Doses useful for treatment of age-related macular degeneration include intravenous doses up to about 300 mg of liposomes/kg of body weight administered intravenously to a subject in need thereof. In certain embodiments, the compositions and methods comprise intravenous administration of the ETC-588 at a dose of about 10 mg of liposomes to about 300 mg of liposomes/kg of a subject's body weight. In particular embodiments, the compositions and methods comprise intravenous administration of ETC-588 at a dose of about 25 mg of liposomes/kg to about 200 mg of liposomes/kg body weight. In specific embodiments, the compositions and methods comprise intravenous administration of ETC-588 at a dose of about 50 mg of liposomes/kg to about 150 mg of liposomes/kg body weight. In certain embodiments, the compositions and methods comprise intravenous administration of ETC-588 at a dose of about 100 mg of liposomes/kg to about 150 mg of liposomes/kg body weight. In other embodiments, the composition and methods comprise an intra-ocular administration of ETC-588 at a dose of about 0.5 mg of liposomes/kg to about 4 mg of liposomes/kg body weight.

It is understood by those of skill in the art that the actual dose of ETC-588 according to the present invention can vary with the route of administration, height, weight, age, severity of illness of the subject, the presence of concomitant medical conditions and the like. For example, an elderly subject with compromised renal or liver function can be treated with an intravenous dose of the ETC-588 that is at the lower range of about 12.5 mg of liposomes/kg body weight dose as part of the therapy. A subject with severe cardiovascular disease or related disorders that is obese with good renal and liver function can be treated with an intravenous dose of the ETC-588 that is, for example, at the upper range of about 150 mg of liposomes/kg body weight dose (e.g., 150 mg of liposomes/kg body weight, 145 mg of liposomes/kg body weight, 140 mg of liposomes/kg body weight and the like) as part of the therapy. These doses achieve a range of circulating concentrations that include the effective dose with an acceptable risk-to-benefit profile.

The dose of ETC-588 can vary over the duration of treatment. For example, a subject can be treated with the dose of 150 mg of liposomes/kg body weight of the ETC-588, intravenously once weekly for 3 weeks and then treated with the dose of 50 mg of liposomes/kg body weight of the ETC-588 once every four months or once per year for the lifetime of the subject. Such intermittent doses can be administered to maintain a reduced size and number of drusens in Bruch's membrane. Intermittent doses during the lifetime of the subject to maintain a reduced volume of lipids in the drusens are within the scope of the present invention.

In certain embodiments, a single high dose (e.g., 150 mg of liposomes/kg body weight or 145 mg of liposomes/kg body weight) of the ETC-588 is administered intravenously to the subject. In other embodiments, one or more high doses of the ETC-588 are administered to the subject followed by one or more of the same or lower doses of the ETC-588 (e.g., 12.5, 25, 50, 75, 100 or 150 mg of liposomes/kg body weight). Additionally, the opposite regimen may be used comprising administration of one or more low doses of the ETC-588 (e.g., about 12.5, 25, 50 mg of liposomes/kg body weight ) followed by one or more of the same or higher doses of the ETC-588 (e.g., about 12.5, 25, 50, 75, 100 or 150 mg of liposomes/kg body weight). For more advanced stages of macular degeneration (e.g., wet forms), the high dose is preferably delivered first.

In certain embodiments, the ETC-588 is administered as an intravenous infusion. In certain embodiments, the compositions and methods comprise administration as a intravenous push infusion. By intravenous push infusion, it is preferred that the ETC-588 is administered intravenously over a short time period, such as up to 5 minutes, for example, 2-5 minutes. In certain embodiments, administration of the ETC-588 comprises a continuous intravenous infusion. By continuous intravenous infusion, it is preferred that the ETC-588 is administered continuously over a period of time, for example, about 1 hour to 3 hours, preferably, about 30 minutes to 120 minutes. Continuous intravenous infusions can be administered with the aid of an infusion pump or device. In certain embodiments, administration of the ETC-588 can be a combination of continuous intravenous infusions and intravenous push infusions ("bolus doses"). The bolus doses can be administered before, after or during the continuous infusion.

The compositions and methods provide for intravenous infusion of the ETC-588. Any suitable blood vessel can be used for infusion, including peripheral vessels, such as the vessels in the antecubital fossa of the arm or a central line into the major veins of the chest. In preferred embodiments, the pharmaceutical formulation is infused into the cephalic or median cubital vessel at the antecubital fossa in the arm of a subject. The infusion may be administered in a hospital or the outpatient section of the hospital, Surgeons' center, emergency room or another urgent care center, infusion center, ophthalmologist's or doctor's office, or with the assistance of a health-care provider in the home.

4.3.4 Timing of Administration of ETC-588

In certain embodiments, the methods for the treatment of age-related macular degeneration or related conditions comprise administering the ETC-588 about every week, about every other week, about every 4, 5, 6, 7, 8 to 10 or 11 to 14 days to a subject in need thereof. In a preferred embodiment, the ETC- 588 can be administered about every 7 days. In certain embodiments, administration of the ETC-588 can be a one-time administration every six months or every year. In certain embodiments, administration can continue for about 1 week, about 2 weeks, about 3 weeks, about 4 weeks, about 5 weeks, about 6 weeks, about 7-12 weeks, about 13-24 weeks or about 25-52 weeks. In certain preferred embodiments, administration of the ETC-588 is about every 7 days for about 5 weeks. In certain embodiments, administration can be intermittent after, for example, about 5 weeks. For example, a subject can be treated once a week for about 5 weeks and then treated about 3 to about 4 times over the following year. In certain embodiments, the pharmaceutical formulations described herein can be administered to the subject intermittently to maintain a reduced size and number of drusens in Bruch's membrane. For example, the ETC-588 in a dose of about 50 mg of liposomes/kg body weight can be administered about every 10 days for about 7 weeks and then administered, for example, about 26 weeks later or about 52 weeks later.

4.4 Patients and Diseases to be Treated by the Therapy

The invention provides novel compositions and methods to treat age-related macular degeneration or related disorders or forms (wet, dry, early, late).

In some embodiments, the compositions and methods of the present invention are to treat age- related macular degeneration or related disorders in subjects with signs or symptoms thereof. Age-related macular degeneration (ARMD) is a clinical diagnosis based upon the presence of visual disturbance and characteristic findings on dilated eye examination. In patients with dry type of ARMD, drusens are visible on dilated eye examination. In such patients, round or oval patches of geographic atrophy of the retina may be evident as areas of depigmentation, increased pigmentation may be seen with RPE pigmentary mottling. In patients with wet type of ARMD₁ dilated examination may reveal subretinal fluid, hemorrhage, and lipid exudates. In such patients, neovascularization appears as a grayish discoloration in the macular area. Additional information on age-related macular degeneration (ARMD), including epidemiology, etiology/risk factors, clinical presentation, diagnosis, treatment and prevention is included in Jorge G. Arroyo, "Age- related macular degeneration-l and II," UpToDate (on-line service) (last modified September 19, 2005), which is hereby incorporated herein by reference.

In one embodiment, the compositions and methods of the invention provide for treating age-related macular degeneration or related disorders in subjects at risk for developing ARMD. A number of possible risk factors have been identified, of which age and smoking are the only factors that appear to definitively increase risk. Additional risk factors are set forth in Jorge G. Arroyo, "Age-related macular degeneration-l and II," UpToDate (on-line service), as referenced above.

Various embodiments of the invention have been described. The descriptions and examples are intended to be illustrative of the invention and not limiting. Indeed, it will be apparent to those of skill in the art that modifications may be made to the various embodiments of the invention described without departing from the spirit of the invention or scope of the appended claims set forth below. All references cited herein are hereby incorporated by reference in their entireties.

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Claims

What is claimed:

1. A method for preventing, ameliorating or treating an age-related macular degeneration or a related condition, comprising administering to a subject a therapeutically effective amount of unilamellar vesicles comprised of phospholipids or a pharmaceutically acceptable salt thereof.

2. The method of claim 1 , wherein said unilamellar vesicles consist essentially of phospholipids which are substantially free of sterol.

3. The method of claim 2, wherein said unilamellar vesicles having an average diameter of about 50 nm to about 200 nm.

4. The method of any one of claim 1 to 3, wherein the phospholipid is selected from the group consisting of phosphatidylcholine, egg phosphatidylcholine, soybean phosphatidylcholine, dipalmitoylphosphatidylcholine, dimyristoylphosphatidylcholine, distearoylphosphatidylcholine, dilaurylphosphatidylcholine, 1-myristoyl-2-palmitoylphosphatidylcholine,

1 -palmitoyl-Σ-myristoylphosphatidylcholine, 1 -palmitoyl-2-stearoylphosphatidylcholine, 1 -stearoyl^-palmitoylphosphatidylcholine, dioleoylphosphatidylcholine, 1 -palmitoyl-2- oleoylphosphatidylcholine, 1-oleoyl-2-palmitylphosphatidylcholine, dioleoylphosphatidylethanolamine, dilauroylphosphatidylglycerol, phosphatidylserine, phosphatidylethanolamine, phosphatidylinositol, phosphatidylglycerol, diphosphatidylglycerol, dimyristoylphosphatidylglycerol, dipalmitoylphosphatidylglycerol, distearoylphosphatidylglycerol, dioleoylphosphatidylglycerol, phosphatidic acid, dimyristoylphosphatidic acid, dipalmitoylphosphatidic acid, dimyristoylphosphatidylethanolamine, dipalmitoylphosphatidylethanolamine, dimyristoylphosphatidylserine, dipalmitoylphosphatidylserine, brain phosphatidylserine, sphingomyelin, brain sphingomyelin, dipalmitoylsphingomyelin and distearoylsphingomyelin.

5. The method of Claim 4, wherein the phospholipid is a 1 -palmitoyl-2- oleoylphosphatidylcholine (POPC).

6. The method of claim 5, wherein said unilamellar vesicles having an average diameter larger than 50 nm.

_ id _

7. The method of claim 5, wherein said unilamellar vesicles having an average diameter larger than 100 nm.

8. The method of claim 5, wherein said unilamellar vesicles having an average diameter larger than 150 nm.

9. The method of claim 5, wherein said unilamellar vesicles having a mean diameter of 125 ± 30 nm.

10. The method of claim 5, wherein said unilamellar vesicles are administered at an intravenous dose of about 10 mg/kg to about 300 mg/kg.

11. The method of Claim 10, wherein said unilamellar vesicles are administered at an intravenous dose of about 25 mg/kg to about 200 mg/kg.

12. The method of Claim 11 , wherein said unilamellar vesicles are administered at an intravenous dose of about 50 mg/kg to about 150 mg/kg.

13. The method of Claim 12, wherein said unilamellar vesicles are administered at an intravenous dose of about 100 mg/kg to about 150 mg/kg.

14. The method of Claim 10, wherein said unilamellar vesicles are administered at an intravenous dose of about 10 mg/kg.

15. The method of Claim 10, wherein said unilamellar vesicles are administered at an intravenous dose of about 100 mg/kg.

16. The method of Claim 10, wherein said unilamellar vesicles are administered at an intravenous dose of about 200 mg/kg.

17. The method of claim 5, wherein said unilamellar vesicles are administered at an intra-ocular dose of about 0.4 mg/kg to about 8 mg/kg.

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18. The method of Claim 5, wherein the disease is nonexudative or dry age-related macular degeneration.

19. The method of Claim 5, wherein the disease is exudative or wet age-related macular degeneration.

20. The method of Claim 5, wherein said unilamellar vesicles are administered as a pharmaceutical formulation.

21. The method of claim 20, wherein the pharmaceutical formulation comprises a buffer comprising phosphate in a concentration of about 10 mM to about 30 mM and sodium chloride in a concentration of about 80 mM to about 200 mM, wherein said buffer having a pH of about 7.0 to 7.8.

22. The method of claim 21 , wherein said buffer is 20 mM phosphate and 130 mM sodium chloride.

23. The method of Claim 22, wherein said buffer having the pH of about 7.4.

24. The method of Claim 23, wherein the pharmaceutical formulation is a sterile liquid pharmaceutical formulation.

25. The method of Claim 23, wherein the pharmaceutical formulation is a lyophilized pharmaceutical formulation.