FORM 2
THE PATENTS ACT, 1970
(39 of 1970)
&
The Patent Rules, 2003
PROVISIONAL SPECIFICATION
[Section 10, and Rule 13]
PHARMACEUTICAL COMPOSITION OF FIDARESTAT AND PROCESS FOR PREPARING
THEREOF
Applicant
Name: Torrent Pharmaceuticals Limited
Nationality: Indian
Address: Torrent House, Off Ashram Road, Near
Dinesh Hall, Ahmedabad 380 009, Gujarat,
India
The following specification describes the invention

TITLE: Pharmaceutical composition of fidarestat and process for preparing thereof.
FIELD OF INVENTION
Present invention relates to pharmaceutical composition of fidarestat having improved solubility and dissolution characteristics and thereby improves bioavailability and process for preparing the said dosage form.
BACKGROUND OF THE INVENTION
Diabetic microvascular complications are the complications of diabetes mellitus that is wholly or in part due to microvascular mediated causes which covers diabetic neuropathy, diabetic keratopathy, diabetic maculopathy and many more.
Diabetic neuropathies are a family of nerve disorders caused by diabetes. People with diabetes can, over time, have damage to nerves throughout the body. Neuropathies lead to numbness and sometimes pain and weakness in the hands, arms, feet, and legs. Problems may also occur in every organ system, including the digestive tract, heart, and sex organs.
Diabetic keratopathy is a disease characterized by various abnormalities in the corneal epithelium, perception and endothelial cells. When the cornea undergoes severe disintegration, vesicular keratopathy occurs and visual function is seriously damaged.
People with diabetes can develop these problems at any time, more particularly in a long run with uncontrolled diabetes.

While many people around the world suffer from one or more diabetic complications, there are currently very few drugs to treat this condition.
Fidarestat is an aldose reductase inhibitor useful for the treatment of diabetic complications and currently under evaluation for diabetic neuropathy.
Fidarestat is chemically known as (2S,4S)-6-fluoro-2,5-dioxospiro[3,4-dihydro-2H-1-benzopyran-4,4-imidazolidine]-2-carboxamide.
Fidarestat contains a spiro hydantoin ring and a carbamoyl group which was shown to be a very effective substituent for affinity to aldose reductase and for selectivity between aldose reductase and aldehyde reductase. Fidarestat is more potent and have shown beneficial effects on sorbitol accumulation in diabetic neuropathy than other aldose reductase inhibitors.
Fidarestat is a sparingly soluble drug with high ionization constant which indicates that the drug will be poorly absorbed from the Gl tract and will result in poor bioavailability which is also supported by the disclosure in the art.
To get desired therapeutic response, It is utmost important that sufficient amount of drug gets absorbed to achieve desired bioavailability. Many techniques are known to person skilled in art for poorly soluble drugs to improve the dissolution and bioavailability and which vary depending on the nature of the drug employed because physicochemical properties, such as solubility, ionization, hydrophilicity, lipophilicity and pharmacokinetic parameters differs for different drugs.
EP0384416 B1 discloses that the composition of the hydantoin derivatives when prepared by the conventional manner shows poor solubility and only

40% absorption which prove relatively low bioavailability of such hydantoin derivatives. EP0384416 does not recommend using surfactant to improve the dissolution and bioavailability because the drug is required to be used for chronic period and use of surfactant may damage the mucosa in the body. Hence, Inventor had tried to solve this problem by preparing the composition of fidarestat with high molecular weight carrier to improve the solubility and absorption.
Hence, there exists a clinical need for other alternatives for composition of fidarestat, that is simple and convenient to manufacture and which provides an improved dissolution profile, uniform clinical effects, and enhances the bioavailability.
Inventors of the present inventors have surprisingly found the simple techniques for preparing pharmaceutical composition of fidarestat which enhances the solubility, dissolution and hence the bioavailability of fidarestat.
SUMMARY OF INVENTION
The first embodiment of the present invention is to provide a stable pharmaceutical composition of fidarestat, which improves the solubility and dissolution profile.
Another embodiment of the present invention is to provide an enhanced bioavailability of fidarestat.
Still another embodiment of the present invention is to provide the composition of fidarestat prepared by the adsorption method.


Yet another embodiment of the present invention is to provide the composition of fidarestat prepared by the complexation with cyclodextrin or povidone or Polaxomers or cremophor or polyoxyl stearates or ion exchange resins.
Yet another embodiment of the present invention is to provide the composition of fidarestat prepared by the solid dispersion method.
Yet another embodiment of the present invention is to provide the pharmaceutical composition of micronized Fidarestat.
Still another embodiment of the present invention is to provide a method of treating an animal, particularly a human being in need of treatment, comprising administering a said composition.
Yet another embodiment of present invention is to provide process for preparing the pharmaceutical composition of fidarestat.
DETAILED DESCRIPTION OF THE INVENTION
The term "composition" as used in this specification and in the appended claims refer to physically discrete units to be administered in single or multiple dosages, each unit containing a predetermined quantity of active material in association with the required one or more excipients. The quantity of active material is that calculated to produce the desired therapeutic effect upon administration of one or more of such units. The composition used herein is selected from tablet, capsule, sachet, pellets, beads, microspheres, microcapsules, pills, powders, lozenges, or granules. Preferably the composition is selected from tablet or capsule.

In one embodiment the solubility and the dissolution of the fidarestat can be enhanced by preparing adsorbate of fidarestat on suitable carrier. This will lead to increase in the surface area of the drug which results in good solubility and improves the dissolution which is required for the desired bioavailability. Adsorption of the fidarestat on the carrier can be done by spraying the drug solution on the carrier alone or blend of carrier and one or more excipients or by solvent evaporation method followed by conventional method of drying and lubrication followed by either compressing it to form tablets or filling it in to capsules using one or more pharmaceutically acceptable excipient.
Carrier used for the preparation of adsorbate of fidarestat may be selected from polymeric carriers like cellulose derivatives such as microcrystalline cellulose, hydroxypropyl cellulose, hydroxy propyl methyl cellulose; pregelatinized starch, starches such as maize, rice, corn and potato starch; super disintegrants such as croscarmellose sodium, sodium starch glycolate, and crospovidone; polyvinyl alcohol; polyvinyl pyrrolidine; solid grades of polyethylene glycol; and non polymeric carriers like lactose, colloidal silica, dicalcium phosphate and cyclodextrin. In particular, lactose monohydrate, sodium starch glycolate or colloidal silica may be preferred either alone or in combination.
Any solvent or blend of solvent known to person skilled in art may be used to prepare the adsorbate of the fidarestat providing it is capable of dissolving the fidarestat. Representative solvents include water, polyhalogenated lower hydrocarbons such as chloroform, methylene chloride, ethylene chloride and

the like; lower alcohols such as methanol, ethanol, propanol, isopropanol, Butanol and the like aromatic solvent such as benzene and toluene, with lower alcohol being the preferred solvent.
In another embodiment the solubility and dissolution of the fidarestat can be improved by micronizing the fidarestat. Micronization is a technique to reduce the particle size of solid material. As dissolution rate of any drug is directly proportional to the surface area of the solid and as reduction in particle size increases the surface area it improves the dissolution rate of the fidarestat. The preferred mean particle size of the fidarestat is of less than about 50 microns; more preffered mean particle size of the fidarestat is of less than about 25 microns and at least about 90% of fidarestat particles have a size of less than about 75 microns, more preffered particle size of at least about 90% of fidarestat particles have a size of less than about 50 microns. Micronization of fidarestat can be done by method selected from pulverization, grinding, and milling. Micronized fidarestat can be formulated in a desired dosage form using any techniques known to a person skilled in art such as wet granulation, direct compression, extrusion & spheronization etc.
In yet another embodiment solubility and dissolution of the fidarestat can be improved by making complex of fidarestat with the cyclodextrin.
"Cyclodextrin" is a cyclic oligosaccharide consisting of at least five saccharide units (e.g., glucopyranose units). For example, the term "cyclodextrin" includes a cyclic molecule containing six or more alpha-D-glucopyranose units linked at the 1,4 positions by alpha linkages, as in amylose, as well as a cyclic molecule containing seven alpha-D-glucopyranose units, as in cycloheptaamylose. The term "cyclodextrin" includes any of the known cyclodextrins, such as unsubstituted cyclodextrins containing from six to

twelve glucose units. Thus, the term "cyclodextrin" includes at least beta-cyclodextrin (beta-CD or BCD), which is commercially available (e.g., product no. C-4805 from Sigma-Aldrich Corp., St. Louis, Mo., USA, cell culture grade [beta]-CD (Schardinger [beta]-Dextrin; Cycloheptaamylose)), as well as alpha-cyclodextrin (alpha-CD or ACD) and gamma-cyclodextrin (gamma-CD or GCD) and/or their derivatives and/or mixtures thereof. The [alpha]-cyclodextrin consists of six glucose units, the [beta]-cyclodextrin consists of seven glucose units, and the [gamma]-cyclodextrin consists of eight glucose units arranged in donut-shaped rings. The term "derivative" of cyclodextrin is meant to include a cyclodextrin molecule wherein some of the OH groups are converted to OR groups. For example, cyclodextrin derivatives include those substituted with lower alkyl groups such as methylated cyclodextrins and ethylated cyclodextrins, wherein R is a methyl or an ethyl group. Lower alkyls contain from 1 to 6 carbon atoms and may be straight chain or branched. In addition, cyclodextrin derivatives include those with hydroxyalkyl substituted groups, such as hydroxypropyl cyclodextrins and/or hydroxyethyl cyclodextrins, wherein R is a -CH2 -CH(OH)2-CH3 or a -CH2CH2-OH group. Substitution may occur at some or all of the hydroxyl groups. By way of example, a derivative of [beta]-cyclodextrin is methyl-[beta]-cyclodextrin (MBCD). The term "methyl-[beta]-cyclodextrin" refers to a [beta]-cyclodextrin having hydroxyl sites substituted by methoxy groups to varying degrees. For example, MBCD can be totally saturated, i.e., 80-100% substituted. "Derivatives" of cyclodextrin also include cyclodextrin derivatives such as hydroxypropyl and sulfobutyl ether cyclodextrins and others. Such derivatives are described for example, in US 4,727,064 and US 5,376,645. Hydroxypropylated [beta]-cyclodextrins (HPBCD) are commercially available (e.g., 2-hydropropyl-[beta]-cyclodextrin, product no. C-0926, Sigma); as are Hydroxypropylated [alpha]-cyclodextrins (HPACD) (e.g., CAVASOL(R) W6 HP, Wacker Biochem Corp. USA, Eddyville, Iowa 52553) and

hydroxypropylated [gamma]-cyclodextrins (HPGCD) (e.g., CAVASOL(R) W8 HP, Wacker Biochem Corp.). Sulfobutyl-ether-[beta]-cyclodextrin are also commercially available.
In the present invention, cyclodextrins to be used are of all kinds of cyclodextrin including above mentioned cyclodextrins, preferably beta cyclodextrin or their derivatives.
In still another embodiment solid dispersion can be used to improve the solubility and dissolution of the fidarestat. The term "solid dispersion" can be described by "the dispersion of one or more active ingredients in an inert carrier matrix at solid state". In some embodiments, the present invention provides a solid dispersion of fidarestat prepared by process described herein, comprising: a) combining fidarestat and a carrier in solution; and b) removing solvent to yield the solid dispersion. Further solvent and cosolvents may be used with two phases of drying. In an alternative embodiment, the present invention provides a solid dispersion of fidarestat prepared by process described herein, comprising: a) combining fidarestat with melted carrier to form a liquid mixture; and b) solidifying the liquid mixture to form the solid dispersion.
The dispersions obtained by above mentioned process may be further processed to form, for example pellets, or in monolithic form, such as tablets using one or more pharmaceutically acceptable excipient.
After mixing and cooling the carrier and fidarestat give a mass that can be treated differently as a function of the particular dosage form. It may be either filled directly in to the capsule or may be compressed in to tablet with one or more pharmaceutically acceptable excipients.

Non-limiting examples of suitable carrier for the solid dispersion of fidarestat include polymers such as celluloses (e. g., carboxymethylcellulose, methylcellulose, hydroxypropylcellulose, hydroxypropylmethylcellulose) ; hyaluronates; alginates; polysaccharides, heteropolysaccharide (pectins) ; poloxamers; poloxamines; ethylene vinyl acetates; polyethylene glycols; dextrans; polyvinylpyrrolidones; chitosans; polyvinylalcohols; propylene glycols; polyvinylacetates; phosphatidylcholines (lecithins); miglyols; polylactic acid; polyhydroxybutyric acid; mixtures of two or more thereof, copolymers thereof, derivatives thereof, and the like. Further example dispersing agents include copolymer systems such as polyethylene glycol-polylactic acid (PEG-PLA), polyethylene glycol- polyhydroxybutyric acid (PEG-PHB), polyvinylpyrrolidone-polyvinylalcohol (PVP-PVA), and derivatized copolymers such as copolymers of N-vinyl purine (or pyrimidine) derivatives and N-vinylpyrrolidone.
The composition of the present invention comprises the fidarestat in a range of about 0.1 mg to 100 mg. Preferably composition may contain 0.4 mg to 50 mg. more preferably composition may contain 0.8 mg to 30 mg.
The term "fidarestat" used herein includes fidarestat free base, pharmaceutically acceptable salts, solvates, enantiomer or mixtures thereof.
The composition of the present invention may also comprise one or more pharmaceutically acceptable excipients.
The pharmaceutically acceptable excipients are selected from the following categories but not limited to diluents, disintegrants, binders, anti-adherents,

lubricants, surfactants, wetting agents, pH modifiers, buffering agents, stabilizers and other excipients known to the person skilled in the art.
Diluent may be selected from lactose, powdered cellulose, microcrystalline cellulose, starch, pregelatinized starch, dibasic calcium phosphate, tribasic calcium phosphate, calcium carbonate, dextrates, dextrin, dextrose, kaolin, magnesium carbonate, magnesium oxide, sugars such as sucrose; sugar alcohols such as mannitol, sorbitol, erythritol; and other materials known to one of ordinary skill in the art. The diluent may be present in an amount ranging from 1 % to 90 % by weight of the composition.
Disintegrant may be selected from croscarmellose sodium, sodium starch glycolate, pregelatinized starch, sodium carboxymethyl cellulose, microcrystalline cellulose, cross-linked polyvinylpyrrolidone, sodium alginate and other materials known to one of ordinary skill in the art. The disintegrant" may be present in an amount ranging from 1 % to 10 % by weight of the composition.
Binder may be selected from hydroxyethyl cellulose, hydroxy propyl cellulose, hydroxy propyl methyl cellulose, carbomers, carboxymethylcellulose sodium, dextrin, ethyl cellulose, methylcellulose, gelatin, polymethacrylates, povidone, pregelatinized starch, sodium alginate, xanthan gum, , guar gum, locust bean gum, carrageenan, carbopol, polyvinyl alcohol, polyvinyl acetate, shellac and other materials known to one of ordinary skill in the art. The binder may be present in an amount ranging from 0 % to 10 % by weight of the composition.
Wetting agents can be selected from the group of surfactants, solubilizers, complexing agents. The preffered wetting agents are surfactants. The surfactant can be selected from

hydrophilic surfactants and lipophilic surfactants, mixtures there of. The surfactants may be anionic, nonionic, cationic, zwitterionic or amphiphilic. The relative hydrophilicity and hydrophobicity of surfactants is described by HLB (hydrophilic-lipophilic balance) value. Hydrophilic surfactants include surfactants with HLB greater than 10 as well as anionic, cationic, amphiphilic or zwitterionic surfactants for which the HLB scale is not generally applicable. Similarly, lipophilic surfactants are surfactants having an HLB value less than 10. The hydrophilic non-ionic surfactants may be, but not limited to, polyethylene glycol sorbitan fatty acid esters, polyethylene glycol fatty acid monoesters, PEG-fatty acid diesters, hydrophilic trans-esterification products of alcohols or polyols with at least one member of the group consisting of natural and/or hydrogenated oils. The most commonly used oils are castor oil or hydrogenated castor oil, or an edible vegetable oil such as corn oil, olive oil, peanut oil, palm kernel oil, almond oil. Preferred polyols include glycerol, propylene glycol, ethylene glycol, polyethylene glycol, sorbitol and pentaerythritol. Preferred hydrophilic surfactants in this class include PEG-35 castor oil, polyoxyethylene-polypropylene copolymer (Lutrol, BASF), and PEG-40 hydrogenated castor oil.
The amphiphilic surfactants includes, but are not limited to, d-[alpha]-tocopheryl polyethylene glycol 1000 succinate and d-[alpha]-tocopherol acid salts such as succinate, acetate, etc.
The ionic surfactants may be, but not limited to, alkylammonium salts; fusidic acid salts; fatty acid derivatives of amino acids, oligopeptides, or polypeptides; glyceride derivatives of amino acids, oligopeptides, or polypeptides; lecithins or hydrogenated lecithins; lysolecithins or hydrogenated lysolecithins; phospholipids or derivatives thereof; lysophospholipids or derivatives thereof; carnitine fatty acid ester salts; salts

of alkylsulfates; fatty acid salts; sodium docusate; acyl lactylates; mono- or di-acetylated tartaric acid esters of mono- or di-glycerides; succinylated mono-or di-glycerides; citric acid esters of mono- or di-glycerides; or mixtures thereof. The lipophilic surfactants may be, but not limited to, fatty alcohols; glycerol fatty acid esters; acetylated glycerol fatty acid esters; lower alcohol fatty acids esters; propylene glycol fatty acid esters; sorbitan fatty acid esters; polyethylene glycol sorbitan fatty acid esters; polyoxyethylene sorbitan fatty acid esters: like polysorbates; sterols and sterol derivatives; polyoxyethylated sterols or sterol derivatives; polyethylene glycol alkyl ethers; sugar esters; sugar ethers; lactic acid derivatives of mono- or di-glycerides; hydrophobic transesterification products of a polyol with at least one member of the group consisting of glycerides, vegetable oils, hydrogenated vegetable oils, fatty acids and sterols; oil-soluble vitamins/vitamin derivatives; polyethylene glycol (PEG) sorbitan fatty acid esters; PEG glycerol fatty acid esters; polyglycerized fatty acid; polyoxyethylene-polyoxypropylene block copolymers; sorbitan fatty acid esters; or mixtures thereof.
Preferably, the surfactant may be PEG-20-glyceryl stearate (Capmul® by Abitec), PEG-40 hydrogenated castor oil (Cremophor RH 40® by BASF), PEG 6 corn oil (Labrafil® by Gattefosse), lauryl macrogol - 32 glyceride (Gelucire 44/14® by Gattefosse), stearoyl macrogol glyceride (Gelucire 50/13® by Gattefosse), polyglyceryl -10 mono dioleate (Caprol® PEG 860 by Abitec), propylene glycol oleate (Lutrol OP® by BASF), propylene glycol dioctanoate (Captex® by Abitec), propylene glycol caprylate/caprate (Labrafac® by Gattefosse), glyceryl monooleate (Peceol® by Gattefosse), glycerol monolinoleate (Maisine® by Gattefosse), glycerol monostearate (Capmul® by Abitec), PEG- 20 sorbitan monolaurate (Tween 20® by ICI), PEG - 4 lauryl ether (Brij 30® by ICI), sucrose distearate (Sucroester 7® by Gattefosse), sucrose monopalmitate (Sucroester 15® by Gattefosse),

polyoxyethylene-polyoxypropylene block copolymer (Lutrol® series BASF), polyethylene glycol 660 hydroxystearate, (Solutol® by BASF), sodium lauryl sulphate, sodium dodecyl sulphate, dioctyl suphosuccinate, L- hydroxypropyl cellulose, hydroxylethylcellulose, hydroxy propylcellulose, propylene glycol alginate, sodium taurocholate, sodium glycocholate, sodium deoxycholate, betains , polyethylene glycol (Carbowax® by DOW), d-[alpha]- tocopheryl polyethylene glycol 1000 succinate (Vitamin E TPGS® by Eastman), or mixtures thereof.
More preferably, the surfactant may be PEG-40 hydrogenated castor oil (Cremophor RH 40® by BASF - HLB - 13), lauryl macrogol - 32 glyceride (Gelucire 44/14® by Gattefosse - HLB - 14) stearoyl macrogol glyceride (Gelucire 50/13® by Gattefosse - HLB - 13), PEG- 20 sorbitan monolaurate (Tween 20® by ICI - HLB - 17), PEG - 4 lauryl ether (Brij 30® by ICI- HLB -9.7), polyoxyethylene-polyoxypropylene block copolymer (Lutrol® series BASF having different HLB ranging from 15-30), Sodium lauryl sulphate (HLB- 40), polyethylene glycol (Carbowax® by DOW), d-[alpha]-tocopheryl polyethylene glycol 1000 succinate (Vitamin E TPGS® by Eastman- HLB -15), or mixtures thereof. The wetting agent may be added intragranularly or extragranularly or in binder solution.
The complexing agent includes cyclodextrin class of molecules, such as cyclodextrins containing from six to twelve glucose units, especially, alpha-cyclodextrin, beta-cyclodextrin, gamma-cyclodextrin, or their derivatives, such as hydroxypropyl beta cyclodextrins, or mixtures thereof. The complexing agents may also include cyclic amides, hydroxyl benzoic acid derivatives as well as gentistic acid. The wetting agent may be present in an amount ranging from about 0 % to about 10 % by weight of the composition, preferably in an amount ranging from about 0.1 % to about 5 % by weight of the composition.

Lubricant may be selected from metallic stearates such as magnesium stearate, calcium stearate, zinc stearate; stearic acid, hydrogenated vegetable oil, hydrogenated castor oil, glyceryl palmitostearate, glyceryl behenate, polyethylene glycols, corn starch, sodium stearyl fumarate, sodium benzoate, mineral oil, talc, and other materials known to one of ordinary skill in the art. The lubricant may be present in an amount ranging from about 0.4 % to about 5 % by weight of the composition.
Glidants may be selected from talc, colloidal silicon dioxide, magnesium trisilicate, powdered cellulose, starch, tribasic calcium phosphate; and other materials known to one of ordinary skill in the art. The glidant may be present in an amount ranging from about 0.1 % to about 5 % by weight of the composition. It would be appreciated if a person skilled in the art is cognizant of the fact that certain excipients can perform the function of lubricant as well as glidant.
The pharmaceutical composition of the present invention may be coated by film forming agent.
Film forming agent may be selected from hydroxy propyl methylcellulose (hypromellose), polyvinylpyrrolidone, gelatin, hydroxy propyl cellulose, polyethylene oxide, hydroxyethyl cellulose, sodium alginate and such like.
The pharmaceutical compositions may additionally contain conventional excipients such as flavoring agents, coloring agent, sweeteners and the like.

The pharmaceutical composition of the present invention can be made using
direct compression, dry granulation, wet granulation or melt granulation
techniques.
In one embodiment, the instant invention can be prepared by the process
given below:
1. Sift diluent and optionally atleast one pharmaceutically acceptable excipient through appropriate sieve.
2. Prepare binder solution containing fidarestat.
3. Spray the binder solution obtained from step 2) over the blend obtained from step 1).
4. Dry the wet granules obtained from step 3).
5. Sift lubricant and optionally atleast one pharmaceutically acceptable excipient and blend them with the dried granules obtained from step 4) through appropriate sieve.
6. Compress the blend of step 5) in to tablets.
7. Tablet obtained from step 6) may optionally be coated using film forming agent.
In a preferred embodiment, the instant invention can be prepared by the process given below:
1. Sift diluent, intra granular disintegrant and glidant through appropriate sieve.
2. Prepare binder solution containing fidarestat.
3. Spray the drug solution obtained from step 2) over the blend obtained from step 1).
4. Dry the wet granules obtained from step 3).

5. Sift lubricant, extra granular disintegrant and glidant and blend them with the dried granules obtained from step 4) through appropriate sieve.
6. Compress the blend of step 5) in to tablets.
7. Tablet obtained from step 6) may optionally be coated using film forming agent.
In another preferred embodiment, the instant invention can be prepared by the process given below:
1. Sift Fidarestat, diluent and optionally atleast one pharmaceutical^ acceptable excipient through appropriate sieve.
2. Prepare binder solution.
3. Spray the binder solution obtained from step 2) over the blend obtained from step 1).
4. Dry the wet granules obtained from step 3).
5. Sift lubricant and optionally atleast one pharmaceutically acceptable excipient and blend them with the dried granules obtained from step 4) through appropriate sieve.
6. Compress the blend of step 5) in to tablets.
7. Tablet obtained from step 6) may optionally be coated using film forming agent.
Throughout this specification and the appended claims it is to be understood that the words "comprise" and "include" and variations such as "comprises", "comprising", "includes", "including" are to be interpreted inclusively, unless the context requires otherwise. That is, the use of these words may imply the inclusion of an element or elements not specifically recited.

Examples
The present invention has been described by way of example only, and it is to be recognized that modifications thereto which fall within the scope and spirit of the appended claims, and which would be obvious to a skilled person based upon the disclosure herein, are also considered to be included within the invention.
Example 1

Sr. No. Ingredient Mg / Tablet
1 Lactose monohydrate (DCL11) 76.50
2 Sodium starch glycolate 5.00
3 Colloidal silicon dioxide 0.65
4 Fidarestat 1.00
5 Methanol q.s
6 Talc 0.45
7 Colloidal silicon dioxide 0.70
8 Sodium starch glycolate 3.00
9 Magnesium stearate 2.70
Total 90.00
Manufacturing Process:
1. Lactose monohydrate and intra granular part of sodium starch glycolate and intra granular part of colloidal silicone dioxide were sifted through appropriate sieve.

2. Fidarestat was dissolved in methanol
3. The material of step 1) was loaded in fluid bed processor and clear drug solution of step 2) was sprayed over the blend.
4. The wet granules of step 3) were dried and sifted through appropriate sieve.
5. The sifted granules of step 4) were blended in a blender.
6. Talc and extra granular part of sodium starch glycolate and extra granular part of colloidal silicon dioxide were sifted through appropriate sieve.
7. Magnesium stearate was sifted through appropriate sieve.
8. The granules of step 5) were blended along with the material of step 6).
9. The blend of step 8) was lubricated with material of step 7) in blender.
10. The blend of step 9) was compressed to tablets.
Example 2

Sr. No. Ingredient Mg / Tablet
1 Lactose monohydrate (DCL11) 76.00
2 Sodium starch glycolate 5.00
3 Colloidal silicon dioxide 0.65
4 Fidarestat (Micronized) 1.00
5 Purified Water q.s
6 Polysorbate 80 0.50
7 Talc 0.45
8 Colloidal silicon dioxide 0.70
9 Sodium starch glycolate 3.00
10 Magnesium stearate 2.70
Total 90.00
Manufacturing Process:

1. Fidarestat, Lactose monohydrate and intra granular part of sodium starch glycolate and intra granular part of colloidal silicone dioxide are sifted through appropriate sieve.
2. Polysorbate 80 is dissolved in purified water.
3. The material of step 1) are loaded in fluid bed processor and solution of step 2) is sprayed over the blend.
4. The wet granules of step 3) are dried and sifted through appropriate sieve.
5. The sifted granules of step 4) are blended in a blender.
6. Talc and extra granular part of sodium starch glycolate and extra granular part of colloidal silicon dioxide are sifted through appropriate sieve.
7. Magnesium stearate is sifted through appropriate sieve.
8. The granules of step 5) are blended along with the material of step 6).
9. The blend of step 8) is lubricated with material of step 7) in blender.
10. The blend of step 9) is compressed to tablets.




ABSTRACT
The present invention contemplates to a pharmaceutical composition of fidarestat exhibiting improved dissolution profile and enhanced bioavailability. Invention also relates to the process for preparing such composition of fidarestat.