Patent Publication Number: US-2006002963-A1

Title: Use of emulsions for intra and periocular injections

Description:
The invention generally relates to a composition for intraocular and periocular injections to treat an eye disease.  
      Delivering therapeutic or diagnostic agents to the posterior segment of the eye, especially to the retina (i.e. the macula) is a challenge.  
      Providing effective amounts of an agent to, for example, the retina via topical instillation is generally not efficient. Topical delivery of drugs often results in limited ocular absorption due to the complex hydrophobic/hydrophilic properties of the cornea and sclera. The composition tends to be quickly removed from the eye by tears and other natural clearing processes. Topical agents are mechanically removed by the blink mechanism such that only approximately 1-5% of the active compounds contained in single drop are absorbed. This amount is mainly distributed into the anterior segment and then eliminated by the physiological aqueous humour pathways. The resulting amount of active compound reaching the posterior segment most often attains sub-therapeutic levels (Koevary, S. B.,  Pharmacokinetics of topical ocular drug delivery: potential uses for the treatment of diseases of the posterior segment and beyond . Curr Drug Metab, 2003. 4(3): p. 213-22).  
      Conversely, ocular absorption of systemically administered pharmacologic agents is limited by the blood ocular barrier, namely the tight junctions of the retinal pigment epithelium and vascular endothelial cells. The barrier limits the size and amount of agents that can reach the choroids and retina. High systemic doses can penetrate this blood ocular barrier in relatively small amounts, but expose the patient to the risk of systemic toxicity. Therefore the dosage is limited so as not to provide a toxic dose of the agent to other parts of the body. This is especially a concern in treating chronic disorders where a long term dosing regimen is typically required.  
      The simplest way to reach the posterior segment eye tissues is the direct intraocular injection. For the posterior segment of the eye, an intravitreal injection has been used to deliver drugs into the vitreous body. U.S. Pat. No. 5,632,984 to Wong et al. relates to the treatment of macular degeneration with various drugs by intraocular injection. The drugs are preferably injected as microcapsules. U.S. Pat. No. 5,770,589 to Billson et al. relates to treating macular degeneration by intravitreally injecting an anti-inflammatory into the vitreous humour. While drug is delivered to the posterior segment, it is not specifically administered to a target area such as the macula, but rather is supplied to the entire posterior segment. Additionally, the procedure has a low risk of infection and retinal detachment. Intraocular drug therapy is considered for many disorders, such as retinal detachment, proliferative vitreoretinopathy (PVR), viral retinitis and uveitis, macular edema (of any origin), proliferation of neo vessels from the retina and/or from the choroid, intraocular inflammation and retinal degenerations (retinal dystrophies).  
      The short half-life of some of the therapeutic agents compels the intravitreal injections to be repeated daily or weekly to maintain therapeutic levels. Several methods of sustained drug-release are currently being investigated to aid in this therapy, with two main products on the market (Vitrasert and Vitravene). These new delivery systems include drug entrapment in liposomes, microspheres, and polymeric materials which control the release of the drug and sustain therapeutic levels over an extended period of time (Slatker, J S et al. (2003).  Anecortave acetate as monotherapy for treatment of subfoveal neovascularization in age - related macular degeneration: twelve - month clinical outcomes . Ophthalmology 110 (12): 2372-2383. Tan, D T et al. (2001).  Randomized clinical trial of Surodex steroid drug delivery system for cataract surgery anterior versus posterior placement of two Surodex in the eye . Ophthalmology 108 (12): 2172-2181. Jaffe, G et al. (2000).  Fluocinolone acetonide sustained drug delivery device to treat severe uveitis . Ophthalmology 107 (11): 2024-2033. Diaz-Llopis, M et al. (1992).  Liposomally - entrapped ganciclovir for the treatment of cytomegalovirus retinitis in AIDS patients. Experimental toxicity and pharmacokinetics, and clinical trial . Peyman G A, et al. (1992).  Clearance of microsphere - entrapped  5- fluorouracil and cytosine arabinoside from the vitreus of primates ). U.S. Pat. No. 5,378,475 describes a device which has been developed for insertion in the vitreous region of the eye, as published in T. J. Smith et al.,  Sustained - Release Ganciclovir , Arch. Ophthalmol, 110, 255-258 (1992) and G. E. Sanborn, et al.,  Sustained - Release Ganciclovir Therapy for Treatment of Cytomegalovirus Retinitis. Use of an Intravitreal Device , Arch. Ophthalmol, 110, 188-195 (1992). U.S. Pat. No. 5,098,443 describes certain specific implants that are inserted through incisions made in the eye wall or sutured around the globe of the eye. These rings may be formed from biodegradable polymers containing microparticles of drug. Initial results indicate that these technologies do retard drug release after injection, but they introduce other problems, such as intravitreal toxicity of the drug carriers, interference with vision and difficulties in the large-scale manufacture of sterile preparations, in addition to their high cost of production.  
      Drug delivery using liposomes and microspheres may be useful in treating posterior segment disease; however, there are also inherent problems encountered with these methods, including manufacturing complexity, sterilisation and production cost. These formulations also spread diffusely within the vitreous cavity and causes cloudiness, interfering with the patient&#39;s visual acuity and the ability of the ophthalmologist to examine the fundus until complete resorption of the formulation has occurred 14-21 days after administration. These problems have led investigators to examine other modes of delivery systems.  
      Despite all the mentioned above, there is still no pharmaceutical formulation (excipient) specifically adapted for intraocular administration. While for hydrophilic molecules this concerns may be easily resolved by administering a sterile isotonic aqueous solution, when the therapeutic agent is hydrophobic the physician is obliged to inject unsuitable products (Nishimura, A et al. 2003 . Isolating triamcinolone acetonide particles for intravitreal use with a porous membrane filter . Retina 23, 777-779).  
      The present invention provides the use of a composition comprising an emulsion and optionally at least a pharmaceutical active ingredient for the manufacture of a medicament in a form adapted for intraocular and periocular administration.  
      According to the instant invention, intraocular administration is intravitreal administration and periocular administration comprises peribulbar, laterobulbar, subconjonctival, sub-tenon and retrobulbar administration.  
      According to the instant invention, the emulsion is preferably an oil/water type emulsion.  
      The present invention also provides a method for treating eye diseases by injecting intraocularely or periocularely a composition comprising an emulsion and optionally at least a pharmaceutical active ingredient.  
      The emulsion is preferably selected from the group comprising anionic and cationic emulsions. Examples of cationic emulsions are the emulsions disclosed in WO 93/18852, i.e. oil/water type emulsion which comprises colloid particles having an oily core surrounded by an interfacial film, the film comprising surface active agents, lipids or both, said emulsions being characterised in that at least part of the surface active agents or lipids in the interfacial film have positively charged polar groups and further in that the colloid particles have a positive zeta potential. The interfacial film may also comprise non-ionic surfactants or lipids.  
      Examples of anionic emulsions are the emulsions described in Klang, S et al. 2 000 . Influence of emulsion droplet surface charge on indomethacin ocular tissue distribution . Pharm Dev Technol 5(4): p. 521-32 and Abdulrazik, M, et al. 2001 . Ocular delivery of cyclosporin A. II. Effect of submicron emulsion&#39;s surface charge on ocular distribution of topical cyclosporin A. STP Pharma Sciences  11(6): p. 427-432., i.e. oil/water type emulsion which comprises colloid particles having an oily core surrounded by an interfacial film, the film comprising surface active agents, lipids or both, said emulsions being characterised in that at least part of the surface active agents or lipids in the interfacial film have negatively charged polar groups and further in that the colloid particles have a negative zeta potential. The interfacial film may also comprise non-ionic surfactants or lipids.  
      In order to have a positive zeta potential the total amount of charges of the cationic agents should be in excess to the total amount of charges of the anionic agents. In order to have a negative zeta potential the total amount of charges of the anionic agents should be in excess to the total amount of charges of the cationic agents.  
      Examples of cationic lipids are C 10 -C 24 -alkylamines and C 12 -C 24 -alkanolamines, C 12 -C 18 -alkylamines and C 12 -C 18 -alkanolamines being preferred. Specific examples of cationic lipids are stearylamine, oleylamine and cholesteryl betainate and various cationic cholesterol esters and derivatives.  
      Examples of anionic lipids are phospholipids. The examples of phospholipids, which may be used in the emulsions of the invention, are lecithins; Epikuron 120.™ (Lucas Meyer, Germany) which is a mixture of about 70% phosphatidylcholine and 12% phosphatidylethanolamine and about 15% other phospholipids; Ovothin 160.™ or Ovothin 200. (Lucas Meyer, phosphatidylcholine, 18% phosphatidylethanolamine and 12% other phospholipids; a purified phospholipid mixture, e.g. such which is obtained from egg yolk; Lipoid E-80.™ (Lipoid A G, Ludwigshafen, Germany) which is a phospholipid mixture comprising about 80% phosphatidylcholine, 8% phosphatidylethanolamine, 3.6% non-polar lipids and about 2% sphingomyeline.  
      Examples of anionic surfactants, which may be included, are sodium lauryl sulphate and alkylpolyoxyethelene sulphate and sulfonate.  
      Examples of non-ionic surfactants, which may be included in the emulsion of the invention, poloxamers such as Pluronic F-68LF.™, Pluronic L-62LF.™ and Pluronic L62D.™ (BASF Wyandotte Corp., Parsippany, N.J., USA), polysorbate such as polysorbate 80, polyoxyethylene fatty acid esters such as EMULPHOR.™ (GAF Corp., Wayne, N.J., USA).  
      The oily phase of the emulsion may comprise one or more members selected from the group consisting of vegetable oil (i.e. soybean oil, olive oil, sesame oil, cotton seed oil, castor oil, sweet almond oil), mineral oil (i.e. petrolatum and liquid paraffin), medium chain triglycerides (MCT) oil (i.e. a triglyceride oil in which the carbohydrate chain has about 8-12 carbon atoms), oily fatty acid, isopropyl myristate, oily fatty alcohols, esters of sorbitol and fatty acids, oily sucrose esters, and in general any oily substance which is physiologically tolerated.  
      The major component of the oily phase will generally be either vegetable oil and/or MCT. Fatty acids or fatty alcohols may be included in cases where the hydrophobic substance to be carried by the emulsion is not sufficiently soluble in the oily phase.  
      Examples of MCT oil, which may be used in emulsions of the present invention, are TCM.™ (Société des Oléagineux, France), Miglyol 812.™ (Dynamit Novel, Sweden).  
      Examples of oily fatty acids, which may be used in emulsions of the invention, are oleic acid, linoleic acid, linolenic acid, palmitic acid, arachidonic acid, lauric acid and others. Examples of fatty alcohols, which may be used, are oleyl alcohol, cetyl alcohol and others. Examples of esters of sorbitol and fatty acids are sorbitan monooleate and sorbiton mono-palmitate. Examples of oily sucrose esters are sucrose mono-, di- or tri-palmitate.  
      As known, the emulsion may also comprise various additives such as osmotic pressure regulators, e.g. sucrose, glycerine or mannitol; anti-oxidants, e.g. alpha-tocopherol, ascorbic acid or ascorbyl palmitate; or preservatives, e.g. methyl-, ethyl-, and butyl paraben. In some applications, other additives may further be included in the substance and, for example, some suitable additives may include dextrose, carriers, stabilizing agents, wetting agents, viscosity enhancers, hydrogels or other similar materials.  
      The preferred ranges of ingredients in the emulsion according to the invention are (expressed in % w/w): oily carrier: 0.5-20%, 0.5-10% being particularly preferred; cationic or anionic surfactants or lipids: 0.01-2%, 0.02-0.4% being particularly preferred and optionally non-ionic surfactant: 0.05-3%, its preferred range being 0.1-2%. Where the emulsion comprises phospholipids: 0.05-3%, 0.1-2% being particularly preferred. These preferred ranges are to be understood as standing each by itself and not cumulative.  
      A preferred pH in the aqueous phase of the emulsion of the invention is 4.0-8.5, 6.0-8.0 being particularly preferred.  
      It is generally preferred that the particles in the emulsion will have a diameter below about 300 nanometers, a diameter less than 200 nanometers being particularly preferred.  
      In the oil/water emulsion, the water-insoluble drug is solubilised in the internal oil phase, thereby remaining in the preferred solution state. In addition, the blurred vision caused by oils is minimised by the water in the external phase. Furthermore, the concentration of the drug in the oil phase can be adjusted to maximise thermodynamic activity, thus enhancing drug penetration to deeper tissues.  
      A wide variety of ocular conditions such as intraocular inflammation, infection, cancerous growth, tumors, neo vessel growth originating from the retina and/or from the choroids, retinal edema, macular edema, diabetic retinopathy, retinopathy of prematurity, degenerative diseases of the retina (macular degeneration, retinal dystrophies), retinal diseases associated with glial proliferation, more specifically, ocular conditions such as glaucoma, proliferative vitreoretinopathy, diabetic retinopathy, age-related macular degeneration, uveitis, cytomegalovirus retinitis, herpes simplex viral retinal dystrophies, age related macular degeneration may be prevented or treated using the cationic or anionic emulsions according to the present invention.  
      Some substances suitable for delivery to the eye may include, for example, anaesthetics, analgesics, cell transport/mobility impending agents such as colchicines, vincristine, cytochalasin B and related compounds; carbonic anhydrase inhibitors such as acetazolamide, methazolamide, dichlorphenamide, diamox and neuroprotectants such as nimodipine and related compounds; antibiotics such as tetracycline, chlortetracycline, bacitracin, neomycin, polymyxin, gramicidin, cephalexin, oxytetracycline, chloramphenicol, rifampicin, ciprofloxacin, aminosides, gentamycin, erythromycin and penicillin, quinolone, ceftazidime, vancomycine imipeneme; antifungals such as amphotericin B, fluconazole, ketoconazole and miconazole; antibacterials such as sulfonamides, sulfadiazine, sulfacetamide, sulfamethizole and sulfisoxazole, nitrofurazone and sodium propionate; antivirals, such as idoxuridine, trifluorothymidine, trifluorouridine, acyclovir, ganciclovir, cidofovir, interferon, DDI, AZT, foscamet, vidarabine, irbavirin, protease inhibitors and anti-cytomegalovirus agents; antiallergenics such as sodium cromoglycate, antazoline, methapyriline, chlorpheniramine, cetirizine, pyrilamine and prophenpyridamine; synthetic gluocorticoids and mineralocorticoids and more generally hormones forms derivating from the cholesterol metabolism (DHEA, progesterone, estrogens); non-steroidal anti-inflammatories such as salicylate, indomethacin, ibuprofen, diclofenac, flurbiprofen, piroxicam and COX2 inhibitors; antineoplastics such as carmustine, cisplatin, fluorouracil; adriamycin, asparaginase, azacitidine, azathioprine, bleomycin, busulfan, carboplatin, carmustine, chlorambucil, cyclophosphamide, cyclosporine, cytarabine, dacarbazine, dactinomycin, daunorubicin, doxorubicin, estramustine, etoposide, etretinate, filgrastin, floxuridine, fludarabine, fluorouracil, florxymesterone, flutamide, goserelin, hydroxyurea, ifosfamide, leuprolide, levamisole, limustine, nitrogen mustard, melphalan, mercaptopurine, methotrexate, mitomycin, mitotane, pentostatin, pipobroman, plicamycin, procarbazine, sargramostin, streptozocin, tamoxifen, taxol, teniposide, thioguanine, uracil mustard, vinblastine, vincristine and vindesine; immunological drugs such as vaccines and immune stimulants; insulin, calcitonin, parathyroid hormone and peptide and vasopressin hypothalamus releasing factor; beta adrenergic blockers such as timolol, levobunolol and betaxolol; cytokines, interleukines and growth factors epidermal growth factor, fibroblast growth factor, platelet derived growth factor, transforming growth factor beta, ciliary neurotrophic growth factor, glial derived neurotrophic factor, NGF, EPO, PLGF, brain nerve growth factor (BNGF), vascular endothelial growth factor (VEGF) and monoclonal antibodies directed against such growth factors; anti-inflammatories such as hydrocortisone, dexamethasone, fluocinolone, prednisone, prednisolone, methylprednisolone, fluorometholone, betamethasone and triamcinolone; decongestants such as phenylephrine, naphazoline and tetrahydrazoline; miotics and anti-cholinesterases such as pilocarpine, carbachol, di-isopropyl fluorophosphate, phospholine iodine and demecarium bromide; mydriatics such as atropine sulphate, cyclopentolate, homatropine, scopolamine, tropicamide, eucatropine; sympathomimetics such as epinephrine and vasoconstrictors and vasodilators. Anticlotting agents such as heparin, antifibrinogen, fibrinolysin, anticlotting activase, antidiabetic agents include acetohexamide, chlorpropamide, glipizide, glyburide, tolazamide, tolbutamide, insulin and aldose reductase inhibitors, hormones, peptides, nucleic acids, saccharides, lipids, glycolipids, glycoproteins and other macromolecules include endocrine hormones such as pituitary, insulin, insulin-related growth factor, thyroid, growth hormones; heat shock proteins; immunological response modifiers such as muramyl dipeptide, cyclosporins, interferons (including alpha-, beta- and gamma-interferons), interleukin-2, cytokines, FK506 (an epoxy-pyrido-oxaazcyclotricosine-tetrone, also known as Tacrolimus), tumor necrosis factor, pentostatin, thymopentin, transforming factor beta.sub.2, erythropoetin; antineogenesis proteins (e.g. anti VEGF, Interfurons).  
      Antibodies (monoclonal or polyclonal) or antibodies fragments, oligoaptamers, aptamers and gene fragments (oligonucleotides, plasmids, ribozymes, small interference RNA (SiRNA), nucleic acid fragments, peptides).  
      Immunomodulators such as endoxan, thalidomide, tamoxifene. Antithrombolytic and vasodilator agents such as rtPA, urokinase, plasmin, Nitric oxide donors.  
      In addition, nucleic acids can also be delivered wherein the nucleic acid may be expressed to produce a protein that may have a variety of pharmacological, physiological or immunological activities.  
    
    
      The invention is further illustrated by the examples and the figures.  
       FIG. 1  describes the ocular inflammation evolution following the intravitreal administration.  
       FIG. 2  illustrates mean inflammation clinical score (A) and retinal injure (B) of the untreated and treated groups. 
    
    
     EXAMPLE 1  
     Preparation of Compositions  
      Composition 1: Cationic Emulsion with Cyclosporine A  
                                                      Cyclosporine A (active)    0.2%           Oleylamine (cationic lipid)    0.1%           MCT (oil)     2%           Alpha tocopherol (antioxidant)   0.01%           Lipoid E80 (surfactant)   0.32%           Lutrol F68 (surfactant)    0.5%           Glycerine (tonicity agent)   2.25%           Water   QSP 100%                      
      Size: 150 nm     Zeta: +58 mV     Osmolarity: 290 mosm     pH adjusted at 8.0 with HCL 0.1N     pH after autoclave=7.3 
 
 Oily phase components and cyclosporine A are successively weighed in the same beaker and then magnetically stirred under a slight heating (40° C.) until a yellow, limpid and slightly viscous phase is obtained. Aqueous phase components are successively weighed in the same beaker and then magnetically stirred under a slight heating (40° C.) until a transparent, limpid and fluid phase is obtained. Both phases are heated to 65° C. The coarse emulsion is formed by rapid addition of the aqueous phase in the oily phase and is then rapidly heated to 75° C. The aqueous phase and coarse emulsion beakers are protected by a film to avoid any water evaporation. The emulsion is white and slightly transparent. The emulsion droplet&#39;s size is then decreased by a 5 minutes high shear mixing with POLYTRON PT 6100. The emulsion becomes milky. The emulsion temperature is cooled down to 20° C. using an ice bath. The final emulsion is obtained by homogenization in a microfluidizer (C5, Avestin) using continuous cycles for 5 min at a pressure of 10 000 psi. The emulsion is milky, very fluid and does not adhere on the glass. The emulsion temperature is decreased to 25° C. Its pH is measured and then adjusted to 8.00 using a 0.1M HCl solution. Emulsion is conditioned in tinted glass vials with nitrogen bubbling and then sterilized in an autoclave 20 minutes at 121° C. 
   

      Composition 2: Cationic Emulsion without Pharmaceutical Active Ingredient.  
                                                      Oleylamine (cationic lipid)    0.1%           MCT (oil)     2%           Alpha tocopherol (antioxidant)   0.01%           Lipoid E80 (surfactant)   0.32%           Lutrol F68 (surfactant)    0.5%           Glycerine (tonicity agent)   2.25%           Water   QSP 100%                      
 
      Composition 3: Anionic Emulsion with Cyclosporine A  
                                                      Cyclosporine A (active)    0.2%           Deoxycholic acid    0.1%           MCT (oil)     2%           Alpha tocopherol (antioxidant)   0.01%           Lipoid E80 (surfactant)   0.32%           Lutrol F68 (surfactant)    0.5%           Glycerine (tonicity agent)   2.25%           Water   QSP 100%                      
 
      Composition 4: Anionic Emulsion with Cyclosporine A  
                                                      Cyclosporine A (active)    0.2%           MCT (oil)     2%           Alpha tocopherol (antioxidant)   0.01%           Lipoid E80 (surfactant)   0.32%           Lutrol F68 (surfactant)    0.5%           Glycerine (tonicity agent)   2.25%           Water   QSP 100%                      
 
      Composition 5: Anionic Emulsion without Pharmaceutical  
                                                      Oleylamine (cationic lipid)    0.1%           Deoxycholic acid    0.1%           MCT (oil)     2%           Alpha tocopherol (antioxidant)   0.01%           Lipoid E80 (surfactant)   0.32%           Lutrol F68 (surfactant)    0.5%           Glycerine (tonicity agent)   2.25%           Water   QSP 100%                      
 
      Composition 6: Cationic Emulsion with Thalidomide  
                                                      Thalidomide (active)    0.1%           Oleylamine (cationic lipid)    0.1%           paraffin (oil)     2%           alpha tocopherol (antioxidant)   0.01%           Lipoid E80 (surfactant)   0.32%           Lutrol F68 (surfactant)    0.5%           Glycerine (tonicity agent)   2.25%           Water   QSP 100%                      
 
      Composition 7: Cationic Emulsion with Medroxyprogesterone  
                                                      Medroxyprogesterone acetate (active)   0.05%           Oleylamine (cationic lipid)    0.2%           Soybean oil (oil)     5%           Ascorbyl palmitate (antioxidant)   0.05%           Lipoid E80 (surfactant)    0.5%           Lutrol F68 (surfactant)    0.8%           Mannitol (tonicity agent)     1%           Water   QSP 100%                      
 
      Composition 8: Cationic Emulsion with Triamcinolone Acetonide  
                                                      Triamcinolone acetonide (active)   0.05%           Oleylamine (cationic lipid)    0.1%           Castor oil (oil)     8%           Alpha tocopherol (antioxidant)   0.05%           Lipoid E80 (surfactant)     1%           Lutrol F68 (surfactant)    0.8%           Mannitol (tonicity agent)     1%           Water   QSP 100%                      
 
      Composition 9: Cationic Emulsion with Dexamethasone  
                                                      Dexamethasone (active)   0.16%           Oleylamine (cationic lipid)    0.1%           MCT (oil)     2%           Alpha tocopherol (antioxidant)   0.01%           Lipoid E80 (surfactant)   0.32%           Lutrol F68 (surfactant)    0.5%           Glycerine (tonicity agent)   2.25%           Water   QSP 100%                      
 
 All compositions 2 to 9 were prepared like composition 1. 
 
     EXAMPLE 2  
     Safety of the Cationic Emulsions Administered Intravitrealy (IVT) to Healthy Animals  
      2.1. Method.  
      10 μL of either saline, empty cationic emulsion (composition 2) or cationic emulsion containing 0.2% cyclosporine A (CsA) (composition 1) were administered IVT to anaesthetized male Lewis rats (8-11 weeks old) (n=2/group).  
      The potential proinflammatory effect of empty cationic emulsions or CsA-cationic emulsions was assessed at 1 and 7 days post-injection by means of a slit lamp according to the scale disclosed by Thillaye-Goldenberg B. et al.,  Delayed onset and decreased severity of experimental autoimmune uvoeretinitis in mice lacking nitric oxide synthase type  2. in J. Neuroimmunol., 2000, vol. 110, 31-44. The score is 0 to 4 according to the following table:  
                                                   Clinical examination   Score                          Full iris dilatation, no cell in the   0           aqueous humeur or vitreous           Partial dilation (mild synechiae)   1           Moderate dilatation (moderate synechiae)   2           Severer synechiae + hypopion   3           As previous + fibrine plugging   4                      
 
 2.2. Results. 
 
 2.2.1. Ocular Inflammation. 
 
      The results are shown in  FIG. 1 .  
      Intravitreal administration of blank emulsion or CsA emulsion do not lead to ocular inflammation.  
     EXAMPLE 3  
     Safety of the Cationic Emulsions Administered Subconjunctivally to Animals  
      3.1. Method.  
      Twenty μL of empty cationic emulsion (composition 2) or cationic emulsion containing 0.2% cyclosporine A (CsA) (composition 1) were administered subconjunctivally to anaesthetized male Lewis rats (n=2/group).  
      3.2. Results.  
      Subconjunctival administration of blank emulsion or CsA emulsion does not lead to any appreciable proinflammatory effect.  
     EXAMPLE 4  
     Efficacy of the CsA-Containing Emulsion Administered IVT in an Animal Model of Posterior Uveitis  
      4.1. Model.  
      Experimental Autoimmune Uveitis (EAU) is an ocular inflammatory disease induced in rodents which serves as a model for the human posterior uveitis (Caspi, RR. et al., 1988 . A new model of autoimmune disease: experimental autoimmune uveoretinitis induced in mice with two difference retinal antigens . J. Immunol. 140: 1490-1495). The onset and duration of the experimental disease are dependent on the Ag immunizing dose, animal species and type of adjuvant. It is a CD4+ T-cell driven disease, leading in one month to destruction of photoreceptor cells and blindness. The ocular inflammation starts at day 12-13 after the systemic immunization with purified retinal autoantigens in adjuvants by an inflammatory cell infiltration, thereafter at 30 days agter immunisation (with Th2-anti-inflammatory: IL-4, IL-10, TGF-β-cytokines playing a role with an increase in Th1 (proinflammatory: IFN-γ, TNF-α, IL-2) cytokines, reaches a peak, and decreases in the resolution of the disease).  
      This immune reaction results in the destruction of the photoreceptor cell, target of the immune response.  
      Although both humoral and cellular immune reactions are stimulated in patients and in animal models, the cell-mediated immunity plays the main role as already described, and therefore there is a rational for CsA administration. Indeed, several studies have demonstrated the therapeutical efficacy of systemic CsA in human uveitis, but the side effects associated to a chronic systemic administration of CsA prevent its extensive use.  
      4.2. Methods.  
      4.2.1. Administration.  
      10 μL of either empty cationic emulsion (composition 2) or cationic emulsion containing 0.2% CsA (composition 1) were administered IVT to anaesthetised male Lewis rats (n=5/group).  
      4.2.2. Ocular Inflammation.  
      The ocular inflammation was assessed during the experimental period as previously described for toxicity experiments in example 1. Significance was evaluated for each time point by the non-parametric Mann-Whitney U test.  
      Probability values &lt;0.05 were considered significant.  
      4.2.3. Histopathology.  
      The retinal damage was evaluated at the time of sacrifice after hematein/eosin/safran in staining under optical microscopy and according to the following score (Ramanathan S. et al.,  Recombinant IL -4  aggravates experimental autoimmune uveoretinitis in rats  in J. Immunol., 1996, vol. 157, 2209-2215).  
                                   Score   Observation                  0   Normal retina       1   Partially damaged extracellular segments       2   Fully damaged extracellular segments       3   Partially damaged photoreceptors nuclei       4   Fully damaged photoreceptors nuclei       5   Partially damaged bipolar cells nuclei       6   Fully damaged bipolar cells nuclei       7   Damage to the ganglion cells                  
 
 Significance was evaluated by the non-parametric Mann-Whitney U test. Probability values &lt;0.05 were considered significant. 
 
 4.3. Results. 
 
 4.4.1. Clinical Inflammation. 
 
      The administration of cyclosporine in the form of a 0.2% emulsion reduced significantly the clinical score of the inflamed eyes during the first days post-injection, compared to the blank emulsion ( FIG. 2A ). For example, at D14 the treated eyes showed a mean value of 1.8±1.3 while all the untreated ones exhibited scores of 4.0. The blank emulsion by itself had no effect compared to saline.  
      4.4.2. Retinal Injury.  
      The retinal damage as evaluated from the examination of histological slides ( FIG. 2B ) suggests that the blank emulsion ameliorates EAU, as from 2.8±1.7 (saline group) the score was lowered to 1.0±0.4 (blank emulsion). Incorporation of CsA to the emulsion further reduced the damage to 0.1±0.3.