WO2010058166A1

WO2010058166A1 - Use of rimcazole for the treatment of ocular disorders

Info

Publication number: WO2010058166A1
Application number: PCT/GB2009/002700
Authority: WO
Inventors: Lisa Patel; Samuel Cameron Williams; Ian Wilding; Martin Read
Original assignee: Modern Biosciences Plc
Priority date: 2008-11-18
Filing date: 2009-11-18
Publication date: 2010-05-27
Also published as: GB0821093D0

Abstract

The present invention relates to the use of Rimcazole or a pharmaceutically acceptable derivative thereof in the treatment of a disease or disorder associated with vessel oedema and/or leakage, for example age-related macular degeneration. In one embodiment, the Rimcazole is administered orally.

Description

USE OF RIMCAZOLE FOR THE TREATMENT OF OCULAR DISORDERS

TECHNICAL FIELD

The present invention relates to a new therapy for diseases or conditions associated with vessel oedema and/or leakage. In particular, the present invention concerns the use of Rimcazole for treating such diseases and conditions.

BACKGROUND

Vessel oedema and leakage is a symptom of a number of diseases and conditions and results from damage to endothelial barrier function which, in turn, leads to endothelial hyperpermeability and plasma leakage through gaps between endothelial cells. Although several mechanisms have been implicated in the improvement of endothelial barrier function, current therapies based on these mechanisms, such as elevation of cyclic AMP by beta- 1 -adrenergic agents, or specific receptor blockers, often fail. In addition, to date therapies have focused on targeting the underlying cause rather than targeting the vessel oedema or leakage specifically.

An example of a disease where vessel oedema and leakage plays a significant role is age related macular degeneration (AMD). AMD is the main cause of blindness among the elderly in developed countries. There are two forms of this disease - exudative (or "wet") and dry. AMD is characterised by two mechanistic pathologies, specifically neovascularisation and vessel leakage/oedema as described in Nowak et al., Pharmacological Reports, 2006, 58, 353-363.

Neovascularisation is the better characterised of the two mechanisms which contribute to AMD. The process involves a balance between a number of stimulating and inhibiting growth factors to regulate the growth of new vessels into areas of hypoxia. Vascular endothelial growth factor (VEGF) and endothelial specific mitogen are regarded as the most important ocular angiogenic factors (Ozaki et al., Am J Pathol 156, 697-707).

The role of vessel oedema and/or leakage and vessel integrity in AMD is less well understood. However, the vessel oedma/leakage pathology is a key feature of this disease and leads to macular edema, bleeding, fibrinous deposits and scar formation.

The most severe form of wet AMD is choroidal neovascularisation (CNV) which leads to a sudden deterioration in central vision which is perceptible within a few weeks. This vision loss is dramatically accelerated by vascular leak from neovascular vessels and hemorrhaging into the retina.

Current therapies for AMD target neovascularisation and, in particular, focus on control of VEGF activity. In addition, more recent research has focused on an investigation of vessel branching and factors such as sprouty (Cabrita et al, Angiogenesis 11(1) 53-62 and Dor et al, Trends Cell Biol 13(3) 131-136). Commercially available therapies include Lucentis, Avastin and Macugen which are normally injected directly into the eye. Such injections can be painful, are associated with potential complications, such as iatrogenic rhegmatogenous retinal detachment, endophthalmitis and cataracts, and typically have to be repeated on a monthly or bi-monthly basis. In addition, it can take some time before the effects of such therapies are observed.

There is therefore a need for a therapy for diseases and conditions associated with vessel oedema and/or vessel leakage which does not suffer from the drawbacks associated with the currently available therapies. In particular, it would be beneficial to identify a therapy which targets the vascular oedema and/or leakage. Where the condition is AMD, it would be desirable to provide a therapy which does not need to be administered intra-vitreally and which can thus additionally be used prophylactically.

DISCLOSURE OF THE INVENTION

The present inventors have surprisingly found that 9-[3-[3,5-dimethylpiperazin-l- yl]propyl]carbazole, i.e. Rimcazole, which has the structural formula I below, is effective when used to treat diseases or conditions associated with vessel oedema and/or vessel leakage.

Formula I More specifically, Rimcazole has been found to be effective for treating AMD.

Rimcazole has been disclosed as having anti-aggressive and anti-psychotic properties (EP 0 012 208 A and US 5,955,459). However, clinical trials of the use of Rimcazole for these indications have not proved conclusive and Rimcazole has not been licensed or marketed for the treatment of aggression or psychoses in humans.

While investigating the effects of Rimcazole using the choroidal neovascularization model of vessel growth, formation and leakage, the inventors surprisingly found that Rimcazole is effective for treating vessel oedema and/or vessel leakage. Advantageously, Rimcazole was found to be faster acting in the treatment of AMD than current commercially available therapies. Furthermore, the inventors noted that these advantageous results were obtained by intra-peritoneal administration, which is a surrogate for oral administration, of the Rimcazole, rather than needing to administer it directly at the target site. Previous studies have shown that Rimcazole is orally bioavailable. Through this model, it is expected that analogous results will be obtained for oral administration of Rimcazole. This is particularly advantageous where the disease or condition is AMD as it avoids the need for painful intra-vitreal administration.

Thus, the present invention provides Rimcazole or a pharmaceutically acceptable derivative thereof for use in treating a disease or condition associated with vessel oedema and/or leakage. Advantageously, where Rimcazole is used to treat such conditions, a rapid onset of action is observed.

The present invention further provides a method for the treatment of a disease or condition associated with vessel oedema and/or leakage, comprising the step of administering a therapeutically effective amount of Rimcazole or a pharmaceutically acceptable derivative thereof to a patient.

Rimcazole has been found to be particularly effective in treating age related macular degeneration (AMD), where a rapid reduction in disease, as compared to currently available therapies, is observed. Advantageously, where the disease is an ocular condition, such as AMD, it has been found that a rapid reduction in the disease is observed where the Rimcazole is administered orally (or via an intraperitoneal route). This is beneficial as it means that painful intra-vitreal injections can be avoided.

Thus, in a preferred embodiment, the invention provides Rimcazole or a pharmaceutically acceptable derivative thereof for use in treating AMD. Preferably the Rimcazole or pharmaceutically acceptable derivative thereof is administered orally.

Rimcazole

9-[3-[3,5-dimethylpiperazin-l-yl]propyl]carbazole (BW 234U) is known as Rimcazole. Methods of synthesising Rimcazole are known in the art, e.g. as described in EP 0 012 208, US 5,955,459 and WO01/74359.

As used herein the term "Rimcazole" includes Rimcazole and pharmaceutically acceptable derivatives thereof. Derivatives include pharmaceutically acceptable salts, amides and solvates of Rimcazole. Derivatives of Rimcazole may also include prodrugs.

Rimcazole has two stereogenic centres at the 3 and 5 positions of the piperazinyl ring and, as used herein, the term "Rimcazole" includes stereoisomers of Rimcazole. In one embodiment, the stereoisomer of Rimcazole is the (3S,5R) isomer, i.e. 9-[3-[(3S,5R)-3,5-dimethylpiperazϊn-l- yl]propyl]carbazole having the structural formula II:

Formula II The "pharmaceutically acceptable salts" of Rimcazole refer to non-toxic acidic/anionic salt forms.

Suitable pharmaceutically acceptable salts include acid addition salts which may, for example, be 5 formed by mixing a solution of the compound according to the invention with a solution of a pharmaceutically acceptable acid such as hydrochloric acid, sulfuric acid, fumaric acid, maleic acid, succinic acid, acetic acid, benzoic acid, citric acid, tartaric acid, carbonic acid or phosphoric acid.

In one embodiment, the pharmaceutically acceptable salt is a hydrochloride salt of Rimcazolε, typically the dihydrochloride salt (Rimcazole dihydrochloride). Preferably the salt is Rimcazole ) dihydrochloride, which is of structural formula III:

Formula III

The term "pharmaceutically acceptable solvate" includes hydrates or solvates formed with common organic solvents. In one embodiment, the hydrate is Rimcazole dihydrochloride monohydrate.

5 The Rimcazole or a pharmaceutically acceptable derivative thereof may have one or more polymorph or amorphous crystalline forms and are also included in the invention.

The term "pharmaceutically acceptable amide" includes compounds formed by the reaction of Rimcazole with a carboxylic acid, e.g. a Ci-β carboxylic acid. The use of pharmaceutically acceptable amides as prodrugs is discussed, for example, in "The Theory and Practice of Industrial Pharmacy", 2nd Edition, Lachman, Lieberman & Kanig, 1976.

The term "prodrug" means a pharmaceutically acceptable form of a functional derivative of Rimcazole (or a salt thereof}, wherein the prodrug may be: 1) a relatively active precursor which converts in vivo to an active prodrug component; 2) a relatively inactive precursor which converts in vivo to an active prodrug component; or 3) a relatively less active component of the compound that contributes to therapeutic biological activity after becoming available in vivo. Conventional procedures for the selection and preparation of suitable prodrug derivatives are described in, for example, EP 0 012 208.

Treatment of diseases

The present invention relates to the use of Rimcazole or a pharmaceutically active derivative thereof for treating diseases or conditions associated with vessel oedema and/or leakage. Diseases or conditions associated with vessel oedema and/or leakage include those where vessel oedema and/or leakage is a symptom of the disease or condition and those where vessel oedema and/or leakage causes the disease or condition.

In one embodiment, the Rimcazole or pharmaceutically active derivative thereof is used to treat diseases or conditions associated with vessel oedema.

In another embodiment, the Rimcazole or pharmaceutically active derivative thereof is used to treat diseases or conditions associated with vessel leakage.

In another embodiment, the Rimcazole or pharmaceutically active derivative thereof is used to treat diseases or conditions associated with vessel oedema and leakage.

In one embodiment, the vessel is a blood vessel. In another embodiment, the vessel is a capillary or micro-capillary.

In some embodiments, the disease or condition may be a disorder selected from the group consisting of ocular disorders and vasculitides.

In one embodiment, the disease or disorder may be selected from the group consisting of disorders of the sclera, cornea, iris anatomy, iris and ciliary body; disorders of the lens, choroid and retina; glaucoma; disorders of the vitreous body and globe; disorders of the optic nerve and visual pathway; large vessel vasculitis; medium vessel vasculitis and small vessel vasculitis.

Disorders of the sclera, and cornea, include episcleritis and scleritis, keratitis, corneal neovascularization, Fuchs' dystrophy, keratoconjunctivitis sicca, iritis and uveitis.

Disorders of the choroid and retina include hypertensive retinopathy, age-related macular degeneration, macular degeneration, retinitis pigmentosa, macular edema, retinopathy, including retinopathy of prematurity, hypertensive retinopathy, sickle-cell retinopathy, genetic retinopathy, solar retinopathy, drug-related retinopathy, retinal angiomatous proliferation, choroidal vasculitis, retinal vasculitis, Eales' disease and retinal vein/artery occlusion.

Other ocular disorders include neovascular glaucoma, river blindness, papillitis, optic nerve vasculitis, Sorsby's Fundus Dystrophy, blindness and Stargardt disease.

Large vessel vaculitis includes Takayasu arteritis or giant cell (temporal) arteritis.

Medium vessel vasculitis includes polyarteritis nodosa, Wegeners granulomatosis, Kawasaki disease or isolated CNS vasculitis.

Small vessel vasculitis includes Churg-Strauss arteritis, microscopic polyarteritis/polyangiitis, hypersensitivity/allergic vasculitis, Henoch-Schonlein purpura, essential cryoglobulinemic vasculitis, vasculitis secondary to connective tissue disorders, including systemic lupus erythematosus, rheumatoid arthritis, relapsing polychondritis and Behcets disease or vasculitis secondary to viral infection, including Hepatitis B and C, HIV, cytomegalovirus, Epstein-Barr virus and parvo B 19 virus.

In some embodiments, the disease or condition is a disorder of the choroid or retina.

In one embodiment, the disease or condition is age related macular degeneration (AMD), in particular an exudative form of AMD.

As used herein, "treatment" includes prophylactic treatment. As used herein, a "patient" means an animal, e.g. a mammal, typically a human, in need of treatment.

The amount of Rimcazole (or a pharmaceutically acceptable derivative thereof) administered should be a therapeutically effective amount where the Rimcazole is used for the treatment of a disease or condition, and a prophylactically effective amount where the compound or derivative is used for the prevention of a disease or condition.

The term "therapeutically effective amount" used herein refers to the amount of Rimcazole (or a pharmaceutically acceptable derivative thereof) needed to treat or ameliorate a targeted disease or condition. The term "prophylactically effective amount" used herein refers to the amount of compound needed to prevent a targeted disease or condition. The exact dosage will generally be dependent on the patient's status at the time of administration. Factors that may be taken into consideration when determining dosage include the severity of the disease state in the patient, the general health of the patient, the age, weight, gender, diet, time and frequency of administration, drug combinations, reaction sensitivities and the patient's tolerance or response to therapy. The precise amount can be determined by routine experimentation, but may ultimately lie with the judgement of the clinician. Administration & Formulation

General

The Rimcazole or pharmaceutically acceptable derivative thereof may be administered as a medicament by enteral or parenteral routes, including intravenous, intramuscular, subcutaneous, transdermal, airway (aerosol), oral, buccal, sublingual, intranasal, rectal, vaginal, and topical administration. The Rimcazole or pharmaceutically acceptable derivative thereof should be assessed for its biopharmaceutical properties, such as solubility and solution stability (across pH), permeability, etc., in order to select the most appropriate dosage form and route of administration for treatment of the proposed indication.

Generally, the Rimcazole or pharmaceutically acceptable derivative thereof will be administered as a foπnulation in association with one or more pharmaceutically acceptable excipients. The term "excipient" includes any ingredient other than Rimcazole which may impart either a functional (e.g drug release rate controlling) and/or a non-functional (e.g. processing aid or diluent) characteristic to the formulations. The choice of excipient will to a large extent depend on factors such as the particular mode of administration, the effect of the excipient on solubility and stability, and the nature of the dosage form.

Typical pharmaceutically acceptable excipients include:

• diluents, e.g. lactose, dextrose, sucrose, mannitol, sorbitol, cellulose and/or glycine;

• lubricants, e.g. silica, talcum, stearic acid, its magnesium or calcium salt and/or polyethyleneglycol;

• binders, e.g. magnesium aluminum silicate, starch paste, gelatin, tragacanth, methylcellulose, sodium carboxymethylcellulose and/or polyvinylpyrrolidone;

• disintegrants, e.g. starches, agar, alginic acid or its sodium salt, or effervescent mixtures; and/or

• absorbants, colorants, flavors and/or sweeteners.

A thorough discussion of pharmaceutically acceptable excipients is available in Gennaro, Remington: The Science and Practice of Pharmacy 2000, 20th edition (ISBN: 0683306472).

Oral administration

The Rimcazole (or a pharmaceutically acceptable derivative thereof) may be administered orally. Oral administration may involve swallowing, so that the compound enters the gastrointestinal tract, and/or buccal, lingual, or sublingual administration by which the compound enters the blood stream directly from the mouth.

Formulations suitable for oral administration include solid plugs, solid microparticulates, semi-solid and liquid (including multiple phases or dispersed systems) such as tablets; soft or hard capsules containing multi- or nano-particulates, liquids (e.g. aqueous solutions), emulsions or powders; lozenges (including liquid-filled); chews; gels; fast dispersing dosage forms; films; ovules; sprays; and buccal/mucoadhesive patches.

Formulations suitable for oral administration may also be designed to deliver the Rimcazole or pharmaceutically acceptable derivative thereof in an immediate release manner or in a rate-sustaining manner, wherein the release profile can be delayed, pulsed, controlled, sustained, or delayed and sustained or modified in such a manner which optimises the therapeutic efficacy of the said compounds. Means to deliver compounds in a rate-sustaining manner are known in the art and include slow release polymers that can be formulated with the Rimcazole to control its release.

Examples of rate-sustaining polymers include degradable and non-degradable polymers that can be used to release the said compounds by diffusion or a combination of diffusion and polymer erosion. Examples of rate-sustaining polymers include hydroxypropyl methylcellulose, hydroxypropyl cellulose, methyl cellulose, ethyl cellulose, sodium carboxymethyl cellulose, polyvinyl alcohol, polyvinyl pyrrolidone, xanthum gum, polymethacrylates, polyethylene oxide and polyethylene glycol.

Liquid (including multiple phases and dispersed systems) formulations include emulsions, suspensions, solutions, syrups and elixirs. Such formulations may be presented as fillers in soft or hard capsules (made, for example, from gelatin or hydroxypropylmethylcellulose) and typically comprise a carrier, for example, water, ethanol, polyethylene glycol, propylene glycol, methylcellulose, or a suitable oil, and one or more emulsifying agents and/or suspending agents. Liquid formulations may also be prepared by the reconstitution of a solid, for example, from a sachet.

The Rimcazole or pharmaceutically acceptable derivative thereof may also be used in fast-dissolving, fast-disintegrating dosage forms such as those described in Liang and Chen, Expert Opinion in Therapeutic Patents 2001, 11(6): 981-986.

The formulation of tablets is discussed in H. Lieberman and L. Lachman, Pharmaceutical Dosage Forms: Tablets 1980, vol. 1 (Marcel Dekker, New York).

Where the disease or condition is an ocular disorder, such as AMD, it is preferred that the Rimcazole or pharmaceutically acceptable derivative thereof is administered orally as this avoids the need for injection directly into the eye which can be painful to the patient. The inventors have surprisingly found that, even when Rimcazole is administered orally, it is effective in treating the ocular disorder in question. This is surprising because it is necessary to administer current therapies via intra-vitreal injection.

More specifically, the majority of current therapies for AMD focus on reducing VEGF level, or blocking the production of VEGF. For example, Macugen® (pegaptanib sodium), is a VEGF antagonist whilst ranibizumab (Lucentis®) is a VEGF-blocking antibody fragment. Both are administered via intra-vitreal injection.

Delivery of drugs via intra-vitreal injection targets therapies directly into the vitreous humour. From here, VEGF blocking therapies are thought to be able to penetrate the retina {(Toxicol Path. 199; 27(50):536-544)). The efficacy of both Lucentis and Avastin in treating AMD via the intra-vitreal route (Bashshur et al, American Journal of Ophthalmology 2006, 142(1), 1-9; Querques et al, Acta Ophthalmologica 2008, 86(6), 694 - 695) in spite of their differing molecular weights (48kDa and 149kDa respectively) indicates that factors such as delivery to the vitreous humour may be important, a feature which is supported by the low diffusion half-life of drugs out of the vitreous after administration (Bakri et al, Ophthalmology 2007, 114(12), 2179-2182).

It has surprisingly been found that Rimcazole is efficacious in treating diseases or conditions associated with vessel oedema and/or leakage when administered systemically, in particular via oral administration. Systemic delivery, in particular oral administration, of Rimcazole results in greater efficacy than delivery of Avastin intra-vitreally. This is particularly surprising given that systemic delivery, in particular via oral administration, of Rimcazole is unlikely to result in significant drug accumulation in the vitreous humour.

In one embodiment, the present invention provides Rimcazole or a pharmaceutically acceptable derivative thereof for use in the treatment of age-related macular degeneration by oral administration. The age-related macular degeneration may be exudative age-related macular degeneration.

In one embodiment, the Rimcazole may be administered orally as a single daily dose. In an alternative embodiment, the Rimcazole may be administered orally in multiple doses daily. In this regard, in one embodiment, the Rimcazole may be administered orally twice a day. In an alternative embodiment, the Rimcazole may be administered orally three times a day. Where administered in multiple oral doses daily, each of the doses may be the same or different.

In one embodiment, the Rimcazole may be administered orally at a dose of at least about 20 mg/day, alternatively at least about 50 mg/day, alternatively at least about 100 mg/day.

In one embodiment, the Rimcazole may be administered orally at a dose of about 600 mg/day or less, alternatively about 550 mg/day or less, alternatively about 500 mg/day or less.

In some embodiments, the Rimcazole may be administered orally at a dose in the range from about 20 to about 600, alternatively from about 50 to about 500, alternatively from about 100 to about 450, alternatively from about 150 to about 400, alternatively from about 200 to about 350, alternatively from about 250 to about 300 mg/day.

In one embodiment, the Rimcazole may be administered orally once a day at a dose in the range from about 50 to about 450, alternatively from about 100 to about 400, alternatively from about 150 to about 350 mg. In an alternative embodiment, the Rimcazole may be administered orally twice a day, wherein each of the two doses is independently in the range from about 10 to about 300, alternatively from about 25 to about 250, alternatively from about 50 to about 225 mg. In such an embodiment, the two doses may be the same or different.

Parenteral administration

The Rimcazole (or a pharmaceutically acceptable derivative thereof) can be administered parenterally.

The Rimcazole (or a pharmaceutically acceptable derivative thereof) may be administered directly into the blood stream, into subcutaneous tissue, into muscle, or into an internal organ. Suitable means for administration include intravenous, intraarterial, intrathecal, intraventricular, intraurethral, intrasternal, intracranial, intramuscular, intrasynovial and subcutaneous. Suitable devices for administration include needle (including microneedle) injectors, needle-free injectors and infusion techniques.

Parenteral formulations are typically aqueous or oily solutions. Where the solution is aqueous, excipients such as sugars (including but restricted to glucose, mannitol, sorbitol, etc.) salts, carbohydrates and buffering agents (preferably to a pH of from 3 to 9), but, for some applications, they may be more suitably formulated as a sterile non-aqueous solution or as a dried form to be used in conjunction with a suitable vehicle such as sterile, pyrogen-free water (WFI).

Parenteral formulations may include implants derived from degradable polymers such as polyesters {i.e. polylactic acid, polylactide, polylactide-co-glycolide, polycapro-lactone, polyhydroxybutyrate), polyorthoesters and polyanhydrides. These formulations may be administered via surgical incision into the subcutaneous tissue, muscular tissue or directly into specific organs.

The preparation of parenteral formulations under sterile conditions, for example, by lyophilisation, may readily be accomplished using standard pharmaceutical techniques well known to those skilled in the art.

The solubility of Rimcazole (or a pharmaceutically acceptable derivative thereof) used in the preparation of parenteral solutions may be increased by the use of appropriate formulation techniques, such as the incorporation of co-solvents and/or solubility-enhancing agents such as surfactants, micelle structures and cyclodextrins.

Inhalation & intranasal administration

The Rimcazole (or a pharmaceutically acceptable derivative thereof) can be administered intranasally or by inhalation, typically in the form of a dry powder (either alone, as a mixture, for example, in a dry blend with lactose, or as a mixed component particle, for example, mixed with phospholipids, such as phosphatidylcholine) from a dry powder inhaler, as an aerosol spray from a pressurised container, pump, spray, atomiser (preferably an atomiser using electrohydrodynamics to produce a fine mist), or nebuliser, with or without the use of a suitable propellant, such as 1,1,1,2- tetrafluoroethane or 1,1,1,2,3,3,3-heptafluoropropane, or as nasal drops. For intranasal use, the powder may comprise a bioadhesive agent, for example, chitosan or cyclodextrin.

The pressurised container, pump, spray, atomizer, or nebuliser contains a solution or suspension of the Rimcazole (or a pharmaceutically acceptable derivative thereof) comprising, for example, ethanol, aqueous ethanol, or a suitable alternative agent for dispersing, solubilising, or extending release of the active, a propellant(s) as solvent and an optional surfactant, such as sorbitan trioleate, oleic acid, or an oligolactic acid.

Prior to use in a dry powder or suspension formulation, the drug product is micronised to a size suitable for delivery by inhalation (typically less than 5 microns). This may be achieved by any appropriate comminuting method, such as spiral jet milling, fluid bed jet milling, supercritical fluid processing to form nanoparticles, high pressure homogenisation, or spray drying.

Capsules (made, for example, from gelatin or hydroxypropylmethylcellulose), blisters and cartridges for use in an inhaler or insufflator may be formulated to contain a powder mix of the compound of the invention, a suitable powder base such as lactose or starch and a performance modifier such as /-leucine, mannitol, or magnesium stearate. The lactose may be anhydrous or in the form of the monohydrate, preferably the latter. Other suitable excipients include dextran, glucose, maltose, sorbitol, xylitol, fructose, sucrose and trehalose.

Formulations for inhaled/intranasal administration may be formulated to be immediate and/or modified release using, for example, PGLA. Modified release formulations include delayed-, sustained-, pulsed-, controlled-, targeted and programmed release.

Transdermal administration

Suitable formulations for transdermal application include a therapeutically effective amount of a Rimcazole (or a pharmaceutically acceptable derivative thereof) with carrier. Advantageous carriers include absorbable pharmacologically acceptable solvents to assist passage through the skin of the host. Characteristically, transdermal devices are in the form of a bandage comprising a backing member, a reservoir containing the compound optionally with carriers, optionally a rate controlling barrier to deliver the compound of the skin of the host at a controlled and predetermined rate over a prolonged period of time, and means to secure the device to the skin.

The Rimcazole or pharmaceutically acceptable derivative thereof may be administered alone or in combination with one or more other drugs (or as any combination thereof).

General

The term "comprising" encompasses "including" as well as "consisting" e.g. a composition "comprising" X may consist exclusively of X or may include something additional e.g. X + Y. The word "substantially" does not exclude "completely" e.g. a composition which is "substantially free" from Y may be completely free from Y. Where necessary, the word "substantially" may be omitted from the definition of the invention.

The term "about" in relation to a numerical value x means, for example, x+10%.

BRIEF DESCRIPTION OF DRAWINGS

Figure 1 illustrates the grading procedure and assignment of disease index for the semi-quantitative assessment of late-phase fluorescein angiography;

Figure 2(a) to (d) show SLO fluorescence angiography images of example retinal lesions seven days after laser photocoagulation and treatment with (a) intravitreal PBS, (b) intravitreal Avastin, (c) intraperitoneal water, and (d) intraperitoneal Rimcazole;

Figure 3 shows the individual disease index score of each retinal lesion imaged in Figures 2(a) to (d) at seven days following laser induced photocoagulation;

Figure 4(a) to (d) show SLO fluorescence angiography images of example retinal lesions fourteen days after laser photocoagulation and treatment with (a) intravitreal PBS, (b) intravitreal Avastin, (c) intraperitoneal water, and (d) intraperitoneal Rimcazole;

Figure 5 shows the individual disease index score of each retinal lesion imaged in Figures 4(a) to (d) at fourteen days following laser induced photocoagulation;

Figure 6 illustrates that Rimcazole inhibits vessel leakage at 7 and 14 days after photocoagulation;

Figure 7 shows SLO fluorescence angiography images 4 minutes after injection of FS at 7 and 14 days after photocoagulation; and

Figure 8 shows Rimcazole plasma concentrations in rats on day 0 of treatment (the day of the laser burn, 4 days after Rimcazole dosing was started).

MODES FOR CARRYING OUT THE INVENTION

The use of Rimcazole in treating a disease or condition associated with vessel oedema and/or vessel leakage was investigated using a choroidal neovascularisation (CNV) model. This is a model of vessel growth and formation, as well as leakage and is used commonly for the profiling of agents for a number of diseases. It is considered to be a good model for human AMD.

Fluorescein angiography is a valuable tool for the evaluation and treatment of a number of retinal diseases and is considered to be the gold standard test for diagnosing neovascular AMD, as well as for the assessment of vessel leakage in preclinical models of CNV.

Fluoroscein angiography involves the injection of sodium fluorescein, which is a small water-soluble molecule, into the venous circulation, commonly through an antecubin vein. Sodium fluorescein is excited by blue light (λ = 465-490 nm) and emits fluorescence as green-yellow light (λ =520-530 nm). The technique allows for the determination of the pattern (classic or occult), boundaries, composition and location of CNV with respect to the foveal centre.

In the examples which follow, Avastin, which is one of the commercially available therapies for AMD, was administered as a positive control. Avastin is a direct inhibitor of new vessel formation.

Examples

Example 1

Animals

Twenty five 12-week old DA rats were used in the study. Prior to procedures animals were surgically anesthetized by intraperitoneal injection of a mixture of Ketamine (37.5%), Dormitor (25%) and sterile water (Pfizer Animal Health, Exton, PA) at 0.2 ml/10Og and pupils were dilated with a combination of topical 1% tropicamide ((Alcon Laboratories, Fort Worth, TX)) and 2.5% phenylephrine (Akorn, Inc., Decatur, IL). All animal experiments conformed to the ARVO Statement on the Use of Animals in Ophthalmic and Vision Research.

Experimental CNV

Experimental CNV was induced unilaterally in five groups of 2-4 month old female Dark Agouti (DA) rats by rupturing Bruch's membrane using laser light photocoagulation (PC). Dye laser PC was performed using a diode-pumped, 532 nm argon laser attached to a slit lamp funduscope, and a handheld planoconcave contact lens applied to the cornea to neutralize ocular power. Eight lesions (532 nm, 150 mW, 0.2 second, 200 μm diameter) were made in a peripapillary distributed and standardized fashion centered on the optic nerve at 500μm radius and avoiding major vessels in each eye. The morphologic end point of the laser injury was identified as the temporary appearance of a cavitation bubble, a sign associated with the disruption of Bruch's membrane. Laser spots that did not result in the formation of a bubble were excluded from the studies.

Treatment with rimcazole dosed by intraperitoneal and intravitreal injection-Study Protocol Rimcazole was administered to animals via both the intra-vitreal route and the intra-peritoneal route as a surrogate for oral dosing and the results obtained are thus expected to mimic those which would be obtained following oral dosing. Avastin (bevacizumab) was administered intra-vitreally as a positive control in the experiment.

In vivo imaging

In vivo image data of CNV and associated leakage was generated using confocal high-resolution SLO Fluorescein Angiography (0.2ml 10% intra-abdominally injected Fluorescein Sodium, FS) and OCT at 7 days after lesion generation and injections. This was followed by a second imaging session 14 days post-procedure. Time points were chosen based on previous studies on the time course of changes in intensity and area of fluorescein staining in angiograms taken after laser PC in non-treated rats. The angiograms showed that fluorescein staining was first observed 4 days after PC and that the intensity of the staining then rapidly increased reaching its peak approximately 10-12 days after photocoagulation. Further assessment was not undertaken as the time course of experimental CNV in these studies indicated that fluorescein leakage begins to decrease 5 weeks after photocoagulation. Baseline reflectance (at 488nm and 790nm) and autofluorescence (ex. 488nm, em. >498nm) images were made prior to injection of FS to help locate lesions in FA images. The arterio-venous phase was recorded immediately after FS injection. Fluorescein angiograms were thereafter recorded one minute after injection and again four minutes after injection. The latter 4 min data sets were used for statistical analysis.

Evaluation and Analysis

The effect of drug treatment was evaluated by semi-quantitative assessment of late-phase fluorescein angiography. Leakage was defined as the presence of a hyperfluorescent lesion that increased in size with time in the late-phase angiogram Figure 1 illustrates the grading procedure and the assignment of disease index.

The intensity and area of staining in late-phase fluorescein angiography was graded by two examiners in a masked fashion. Angiograms were graded as follows: Score 0, no staining (leakage >100μm diameter); score 1, slightly stained (>100μm diameter); score 2, moderately stained (>300μm diameter); score 3, strongly stained (>500μm diameter) and the score was evaluated by a relevant statistical test, where each substance was compared against the relevant control group. When the two scores given for a particular lesion did not coincide, the higher score was used for the analysis. Such discrepant scoring was observed in <10% of lesions analyzed, and the discrepancy was never by more than one grade. Values of P < 0.05 were considered statistically significant for all forms of statistical analysis used.

Results

As shown in Figures 2(a) to (d) and 3, there were differences in leakage between Rimcazole and positive and negative controls seven days after the photocoagulation procedure. In Figure 3, the disease index was assessed by two masked observers and in the case of discrepancy the higher grading was used in the analysis. Statistically significant differences between groups were assessed by RANOVA. *p<0.05. The angiogram images clearly show the therapeutic benefit of early treatment with intraperitoneal Rimcazole.

Fourteen days after procedure limited choroidal neovascularization, as evidenced by the number of large leakages (grade 2), was maintained in the groups that had received treatment with either intraperitoneal rimcazole on intravitreal Avastin, while in the two control groups leakage had increased significantly (Figure 3 and Figure 4(a) to (d)). In Figure 5, individual Disease Index Score of each retinal lesion at 14 days following laser induced photocoagulation. Disease index was assessed by two masked observers and in the case of discrepancy the higher grading was used in the analysis. Statistically significant differences between groups were assessed by RANOVA. *p<0.05

Fourteen days following the procedure there was a significant difference in retinal leakage between the group that had received intraperitoneal injection of Rimcazole and its relevant control group (p <0.05). There was also a significant difference between the group that had received vitreally injected Avastin and the respective control (p <0.025). There was more leakage in retinae that had received intravitreal injection of PBS compared to the i.p group. This increased leakage in the group which received the intravitreal injection was likely due to the damage caused by this ocular procedure. Overall retinal leakage in the group receiving intraperitoneal rimcazole was comparable to the group that had received intravitreal Iy injection of Avastin.

Figures 4(a) to (d) and 5 show the therapeutic benefit of early treatment with Rimcazole administered by intraperitoneal injection and Avastin administered by intravitreal injection directly compared to the comparative vehicle and route of administration controls.

Avastin treatment led to a reduction in choroidal fluorescence which is indicative of a reduction in new vessel formation. This pattern, in combination with the intense staining of the major vessels is consistent with its general mode of action as a direct inhibitor of new vessel formation. In contrast, treatment with Rimcazole leads to a pattern of diffuse fluorescence unaccompanied by intense major vessel staining which is seen very shortly after fluorescein administration. This reflects a generalised reduction in oedema from vessels of the choroid and the retina. This pattern is consistent with an inhibition of vessel leakage rather than an inhibition in new vessel formation as seen with Avastin.

This is further supported by the difference in time to onset of action between Avastin and Rimcazole. More specifically, while Rimaczole showed statistically significant reductions in disease after 7 days of treatment, whereas it is necessary to administer Avastin for 14 days in order to observe an effect.

Example 2

Example 2 was carried out as detailed in Example 1 but with the exception that blood samples were taken from the animals 4 hours post dose on days 0 and 14 of treatment. Samples were processed for separation of plasma and plasma samples were analysed for the presence of Rimcazole using the following procedure.

Plasma samples were mixed 1 in 10 with a 5% v/v ammonia solution and extracted by the addition of 25 equivalents of extraction solvent (95 parts hexane and 5 parts isopropyl alcohol). Extraction was completed by vortexing for 10 minutes and centrifugation at 4000rpm for 10 minutes at 4⁰C. The resulting supernatant was freeze-dried and reconstituted into 90:10 methanol: 2mM ammonium acetate v/v prior to injection to liquid chromatography-mass spec (LC-MS/MS). Chromatographic separation was achieved using a Supelcosil LC-ABZ 4.6 X 50 mm, 5 μm column under isocratic conditions. Column temperature was 35⁰C with a run time of 3 minutes at a flow rate of 0.9ml/min. Mass spectrometric conditions for Rimcazole were as MS/MS transition of 322.3 180.2 (m/z) and a collision energy of 45 volts. Data analysis was conducted by the peak integration of Rimcazole against a calibration curve. A weighted least squares regression analysis was used to obtain a linear equation over the range of the calibration. Evaluation

The effect of drug treatment was evaluated by quantitative assessment of late-phase (4 ±1 minutes after FS injection) fluorescein angiography. Leakage was defined as the presence of hyperfluorescent areas corresponding with lesions in reflectance images. Prior to quantification the gain and brightness of all images used in analysis were normalized. The intensity and area of leakage in late-phase fluorescein angiography was quantified by multiplying the diameter of leakage (μm) with the mean pixel brightness value (0 to 1) in that area. One-way ANOVA and unpaired tests were used to compare results between test groups. Values of P < 0.05 were considered statistically significant for all forms of statistical analysis used. The data are presented in Table 1 and Figure 6. Data are shown as means ± SEM unless otherwise noted. Before image analysis was performed identification was scrambled and quantification was undertaken in masked fashion.

Table 1

Results

As illustrated in Table 1 and Figure 6, Rimcazole demonstrated a statistically significant dose- dependent ability to limit the development of choroidal neovascular disease secondary to laser induced photocoagulation in rats when administered by intraperitoneal injection on day -4 to day 14 following laser photocoagulation on day 0 when compared to vehicle (one-way ANOVA, p<0.001,df=5, Figure 6 and Table 1). When analyzing the drug-dose response relationship, and once statistical significance for the drug dose response was established by one-way ANOVA, posthoc t- test analysis demonstrated that, the lowest dose of 5mg/kg/day showed a statistically significant reduction in the vascular leak associated with CNV (t-test 5mg/kg/day, p<0.029, t=2.23, df>50) as did the lOmg/kg/day with this dose being statistically a more robust effect than the 5mg/kg/day dose (t test 5mg/kg/d vs 10mg/kg/day, p<0.002, t=3.18, df>50). However, the effect observed at the 5mg/kg/day dose was of smaller magnitude compared to all higher doses. A dose of 10mg/kg/day was the lowest dose which showed a near maximal response. Analysis of the 7 day data also suggests that a dose between 10-15mg/kg/day was the minimally effective dose in controlling vascular leak associated with laser induced CNV and showed a near identical trend in the day 7 analysis.

Examples of SLO-FA images 4 mins after injection of FS are shown in Figure 7. Scans of the vehicle animals show signs of choroidal neovascularisation as demonstrated by intense white areas of staining. These areas are reduced with Rimcazole treatment, with little or no evidence of vascular leakage seen in the 15, 20 and 25mg/kg/d treatment groups.

Analysis of blood samples taken from the treated animals at Day 0 and Day 14 of treatment show that Rimcazole concentrations increase in plasma with dose. These data can be seen in Figure 8 and Table 2 which show that rimcazole is efficacious at plasma levels of between 29ng/ml and 1419ng/ml.

Table 2

Claims

1. Rimcazole, or a pharmaceutically acceptable derivative thereof, for use in the treatment of a disease or condition associated with vessel oedema and/or leakage.

2. Rimcazole, or a pharmaceutically acceptable derivative thereof according, to claim 1, wherein the disease or condition is selected from the group consisting of ocular disorders and vasculitides.

3. Rimcazole, or a pharmaceutically acceptable derivative thereof according, to claim 2, wherein the disease or condition is selected from the group consisting of disorders of the sclera, cornea, iris anatomy, iris and ciliary body; disorders of the lens, choroid and retina; glaucoma; disorders of the vitreous body and globe; large vessel vasculitis; medium vessel vasculitis and small vessel vasculitis.

4. Rimcazole, or a pharmaceutically acceptable derivative thereof, according to claim 3, wherein the disease or condition is selected from the group consisting of ocular vasculitis including episcleritis and scleritis including peripheral ulcerative keratitis, retinal vasculitis; choroidal vasculitis; optic nerve vasculitis and papillitis; inflammatory vasculopathy; Behcets disease, Wegener's granulomatosis; age-related macular degeneration; uveitis; neovascular glaucoma; polypoidal choroidal vasculopathy; Eales' disease; retinal angiomatous proliferation; Sorsby's Fundus Dystrophy; and Stargardt disease.

5. Rimcazole, or a pharmaceutically acceptable derivative thereof, according to claim 3, wherein the disease or condition is a choroid or retina disorder.

6. Rimcazole, or a pharmaceutically acceptable derivative thereof, according to claim 5, wherein the disease or condition is age-related macular degeneration.

7. Rimcazole, or a pharmaceutically acceptable derivative thereof, according to claim 6, wherein the disease or condition is exudative age-related macular degeneration.

8. Rimcazole, or a pharmaceutically acceptable derivative thereof, according to any preceding claim, wherein the Rimcazole or a pharmaceutically acceptable derivative thereof is for oral adminstration.

9. Rimcazole, or a pharmaceutically acceptable derivative thereof, for use in treating age-related macular degeneration by oral administration.

10. Rimcazole, or a pharmaceutically acceptable derivative thereof, according to claim 9, wherein the age-related macular degeneration is exudative age-related macular degeneration.

11. A method for the treatment of a disease or condition associated with vessel oedema and/or leakage, comprising the step of administering a therapeutically effective amount of Rimcazole, or a pharmaceutically acceptable derivative thereof, to a patient.