Title of Invention

CLOPIDOGREL

Abstract A process for preparing an amorphous salt of clopidogrel comprising the step of recovering salt of clopidogrel from a solution thereof under conditions in the presence of a solvent or solvent mixture whereby an amorphous product is obtained.
Full Text FORM 2
THE PATENTS ACT, 1970
(39 of 1970)
&
THE PATENTS RULES, 2003
COMPLETE SPECIFICATION
(See section 10, rule 13)



"CLOPIDOGREL"

CIPLA LIMITED, of 289 Bellasis Road, Mumbai Central, Mumbai - 400 008, India.
The following specification particularly describes the invention and the manner in which it is to be performed.
GRANTED 5-7-2007


ORIGINAL
179/MUMNP/05

FIELD OF THE INVENTION
The present invention relates to amorphous clopidogrel, pharmaceutical compositions, medicaments and products containing the same, processes for preparing amorphous clopidogrel and to therapeutic uses and therapeutic methods of treatment employing amorphous clopidogrel or such pharmaceutical compositions, medicaments or products.
BACKGROUND AND PRIOR ART
Clopidogrel is the international non-proprietary name of methyl (S)-a-(2-chlorophenyl)-6,7-dihydrothieno[3,2-c]pyridine-5(4H)-acetic acid methyl ester. Clopidogrel is a well known antithrombotic agent and the preparation thereof is described in European patent 0099802B.
European patent 028 1459B describes enantiomers of clopidogrel, in particular the preparation of the bisulfate salt of the (+), or dextro rotatory, form of clopidogrel, also known as clopidogrel bisulfate Form 1.
European patent application 1087976A describes a further polymorph of the bisulfate salt of the (+) form of clopidogrel, known as clopidogrel bisulfate Form.
STATEMENT OF THE INVENTION
Accordingly, the present invention relates to a pharmaceutically acceptable salt of clopidogrel, in an amorphous form, essentially free from any crystalline form of clopidogrel.
Further, the present invention relates to a pharmaceutically acceptable preparation comprising an effective amount of a salt together with an excipient matrix comprising at least a homopolymer or copolymer of N-vinyl pyrrolidone, wherein said homopolymer or copolymer of N-vinyl pyrrolidone is complexed with said amorphous pharmaceutically acceptable salt of clopidogrel.
Also, the present invention relates to a pharmaceutically acceptable composition for administering to an animal patient in need of treatment for thrombotic disorders, which composition comprises an effective amount of a slat of clopidogrel together with a pharmaceutically acceptable carrier, diluent or excipient therefor.

Further, the present invention relates to a process for preparing an amorphous salt
of clopidogrel comprises recovering said salt of clopidogrel from a solution thereof under conditions whereby an amorphous product is obtained.
SUMMARY OF THE INVENTION
Hitherto known crystalline salts of clopidogrel have exhibited certain disadvantages, in particular in terms of their low solubility and in connection with the pharmaceutical formulation thereof. Improvement in the physical characteristics associated with known clopidogrel salts would potentially offer a more beneficial therapy utilizing clopidogrel and enhanced manufacturing capabilities therefore.
We have found that the problems associated with the known crystalline forms of clopidogrel can be reduced, or overcome, by using amorphous clopidogrel.


DETAILED DESCRIPTION
In one aspect, the invention provides amorphous clopidogrel and pharmaceutically acceptable salts thereof
The term "pharmaceutically acceptable salt" as used herein refers to salts
which are known to be non-toxic and are commonly used in the pharmaceutical
literature. Typical inorganic acids used to form such salts include hydrochloric,
hydrobromic, hydroiodic, nitric, sulfuric, phosphoric, hypophosphoric, and the
like. Salts derived from organic acids, such as aliphatic mono and dicarboxylic
acids, phenyl-substituted alkanoic acids, hydroxyalkanoic and hydroxyalkandioic
acids, aromatic acids, aliphatic and aromatic sulfonic acids, may also be used.
Such pharmaceutically acceptable salts thus include acetate, phenylacetate,
trifluoroacetate, acrylate, ascorbate, benzoate, chlorobenzoate, dinitrobenzoate,
hydroxybenzoate, methoxybenzoate, methylbenzoate, o-acetoxybenzoate,
naphthalene-2-benzoate, bromide, isobutyrate, phenylbutyrate, beta
hydroxybutyrate, chloride, ciimamate, citrate, formate, fumarate, glycolate,
heptanoate, lactate, maleate, hydroxymaleate, malonate, mesylate, nitrate, oxalate,
phthalate, phosphate, monohydrogenphosphate, dihydrogenphosphate,
metaphosphate, pyrophosphate, propionate, phenylpropionate, salicylate,
succinate, sulfate, bisulfate, pyrosulfate, sulfite, bisulfite, sulfonate,
benzenesulfonate, p-bromophenylsulfonate, chlorobenzenesulfonate,
ethanesulfonate, 2-hydroxyethanesulfonate, methanesulfonate, naphthalene- 1 -sulfonate, naphthalene-2-suifonate, p-toluenesulfonate, xyrlenesulfonate, tartarate, and the like. A preferred salt is the bisulfate salt.
In one particularly preferred embodiment, the invention provides the bisulfate salt of the (+) form of clopidogrel, in an amorphous form.
The present invention also provides amorphous clopidogrel bisulfete having an X-ray diffraction pattern as shown in Figure 1.
US 6284277 describes a freeze-dried formulation said to consist of an amorphous phase and a crystalline phase. The amorphous phase consists predominantly of mannitol and an active ingredient, and the crystalline phase consists predominantly of alanine. Clopidogrel is named as a possible active in the

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list spanning columns 6 to 9 of US 6284277. However, although it is claimed that the amorphous phase cryoprotects the active, we have found that when crystalline and amorphous phases are brought together in this way, the active converts to the crystalline phase. The crystalline alanine has a seeding effect, thus triggering the transformation.
The term "amorphous" as used herein denotes a physical state which is not crystalline and may be verified by X-ray diffraction and other means including but not limited to observation with a polarized light microscope and differential scanning calorimetry. More particularly, amorphous clopidogrel in accordance with the present invention is preferably essentially free from any crystalline form of clopidogrel.
Amorphous clopidogrel according to the present invention exhibits a number of advantages compared to crystalline forms of clopidogrel.
For example, our studies have indicated that amorphous clopidogrel according to the present invention is stable. It may be preferred, however, that conversion of amorphous clopidogrel according to the present invention to a crystalline form may be further obviated by the addition of any number of stabiliser materials known in the art, such as, for example, a PVP polymer, hydroxypropyl methylcellulose (HPMC), hydroxypropylcellulose (HPC), polyethylene glycol (PEG), cyclodextrin, and the like. Furthermore, in terms of stability, we have also demonstrated that amorphous clopidogrel according to the present invention is substantially non-hygroscopic.
In particular the present invention further provides amorphous clopidogrel substantially as hereinbefore described together with a PVP polymer and more particularly there is further provided by the present invention a pharmaceutically acceptable preparation comprising an effective amount of amorphous clopidogrel substantially as hereinbefore described, together with an excipient matrix comprising at least a homopolymer or copolymer of N-vinyl pyrrolidone, wherein said homopolymer or copolymer of N-vinyi pyrrolidone is complexed with said amorphous clopidogrel.

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A homopolymer of N-vinyl pyrrolidone suitable for use according to the present invention can comprise water soluble polyvinylpyrrolidones, such as PVP K-12, PVP K-15, PVP K-17, PVP K-25, PVP K-30, PVP 1-60, PVP 1-90 and PVP 1-I20. Preferably PVP K-30, PVP K-60 or PVP K-90 is employed according to the present invention, in particular PVP K.-30. Alternatively. A homopolymer of N-vinyl pyrrolidone suitable for use according to the present invention might comprise a water insoluble cross linked polyvinylpyrrolidone. A water insoluble cross linked polyvinylpyrrolidone that might be employed according to the present invention can include crospovidone.
Suitably, such complexes present in preparations according to the present invention are easily isolated in the form of stable powders which exhibit excellent handling properties. Pharmaceutical preparations according to the present invention can, for example, be easily and conveniently processed into final dosage forms (such as tablets, capsules and the like) substantially as hereinafter described in greater detail without the need for substantial stabilising precautions during processing.
Amorphous clopidogrel according to the present invention can be further characterised as having a solubility in the range of about 0.2 to 0.3 g/ml in methanol, typically about 0.25 g/ml, which is approximately 1.5 times greater than the solubility of a crystalline form of clopidogrel. Advantages of increased solubility include, but are not limited to, improved bioavailability, ease in processing the amorphous material, ease in formulation and delivery of the material, and the like.
Amorphous clopidogrel according to the present invention also exhibits a low bulk density in the range of about 0.2 to 0.5 g/ml compared to crystalline forms exhibiting a density in the range of about 0.6 to 0.9g/ml. This low density can offer further advantages in terms of formulation of dosage forms, for example milling operations might be avoided which in turn might lead to avoidance of racemisation due to heat sensitivity and / or abrasion.
Amorphous clopidogrel according to the present invention can also be

WO 2004/026879 PCT/GB2003/003988

further characterised as having a melting point in the range of 85 to 95°C, more typically in the range of 88 to 92°C and even more typically a melting point of about 90°C. Crystalline clopidogrel exhibits a melting point in the range of about 174 tol86°C.
As hereinbefore described, clopidogrel is an antithrombotic agent. More particularly, clopidogrel inhibits platelet aggregation.
Amorphous clopidogrel according to the present invention is therapeutically useful in the treatment of symptoms of, and / or occurrence of, thrombotic disorders in animal patients. The term "treatment" as used herein denotes the management and care of an animal patient for the purpose of combating thrombotic disorders and includes the administration of amorphous clopidogrel of the present invention to prevent the onset of the symptoms or complications associated with thrombotic disorders, alleviating or ameliorating the symptoms or complications associated with thrombotic disorders, or substantially eliminating thrombotic disorders. The term "thrombotic disorders" as used herein denotes a disorder relating to, or affected with, the formation or presence of a blood clot within a blood vessel. Thrombotic disorders include, but are not limited to, prior and acute myocardial infarction, unstable and stable angina, acute reocclusion after percutaneous transluminal coronary angioplasty (PTCA), restenosis, thrombotic stroke, prior transient ischemic attack (TIA) and reversible ischemic neurological deficit (RIND). Amorphous clopidogrel according to the present invention can be particularly suitable for use in the prevention of recurrence of secondary ischemic events following a primary ischemic event.
The present invention further provides for pharmaceutically acceptable compositions for administering to an animal patient, including humans, in need of treatment for thrombotic disorders, which comprises an effective amount of amorphous clopidogrel as described herein (optionally provided by a pharmaceutically acceptable preparation substantially as hereinbefore described), together with a pharmaceutically acceptable carrier, diluent or excipient therefor.
As used herein, the term "effective amount" means an amount of

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amorphous clopidogrel which is capable of treating (for example inhibiting, alleviating, ameliorating or preventing) thrombotic disorders.
By "pharmaceutically acceptable preparation" it is meant that the excipient matrix component or components must be compatible with amorphous clopidogrel of the preparation, and not be deleterious to the recipient thereof
By "pharmaceutically acceptable composition" it is meant that the carrier, diluent or excipient must be compatible with amorphous clopidogrel of the composition, and not be deleterious to the recipient thereof Pharmaceutical compositions can be prepared by procedures known in the art. For example, amorphous clopidogrel of this invention can be formulated with common carriers, diluents or excipients, and formed into tablets, capsules, and the like. Examples of carriers, diluents or excipients that are suitable for such compositions include the following: fillers and extenders; binding agents; moisturising agents; surface active agents; and lubricants. Final pharmaceutical forms may be: pills, tablets, powders, lozenges, sachets, cachets, or sterile packaged powders, and the like, depending on the type of excipient used.
The particular dosage of amorphous clopidogrel required to treat, inhibit, or prevent thrombotic disorders as described herein in an animal patient, including humans, will depend upon the particular thrombotic disease or condition, and the symptoms, and severity thereof Dosage, routes of administration, and frequency, of dosing is best decided by an attending physician. When the compositions of the invention are administered to an animal patient by the oral or parenteral route, it is typically preferable that the daily dose of amorphous clopidogrel is in the range of 50 and 100 mg.
Compositions according to the present invention are, however, preferably made so as to be administrable by the oral or parenteral route.
Pharmaceutical compositions of the present invention may be administered in unit forms, for example the forms for oral administration include tablets, gelatin capsules, powders, granules and oral solutions or suspensions.
When a solid composition in the form of tablets is prepared, amorphous

WO 2004/026879 PCT/GB2003/003988
clopidogrel can be mixed with a pharmaceutical vehicle such as gelatin, starch, lactose, magnesium stearate, talc, gum arabic and the like. The tablets can be coated with sucrose or other appropriate materials or alternatively they can be treated such that they have a prolonged or delayed activity and that they continuously liberate a predetermined quantity of amorphous clopidogrel.
A preparation in the form of gelatin capsules can be obtained by mixing amorphous clopidogrel with a diluent and by pouring the mixture obtained into soft or hard gelatin capsules.
The water-dispersible granules or powders may contain amorphous clopidogrel mixed with dispersing agents or wetting agents, or suspending agents, such as polyvinylpyrrolidone, as well as sweeteners or flavour enhancers.
For parenteral administration, aqueous suspensions, isotonic saline solutions, or sterile and injectable solutions, can be used which contain dispersing agents and/or wetting agents which are pharmacologically compatible, for example propylene glycol or butylene glycol.
Amorphous clopidogrel can also be formulated in the form of microcapsules, optionally with one or more carriers or additives.
As a further embodiment of the invention, amorphous clopidogrel may be administered along with an effective amount of an additional therapeutic agent, including one or more further antithrombotic agents that might exhibit synergistic activity with amorphous clopidogrel according to the present invention. The different forms of these additional antithrombotic therapeutic agents available and the applicable dosing regimens are well known to those of skill in the art. The present invention, therefore, further provides a product containing amorphous clopidogrel and one or more further antithrombotic agents, for simultaneous, separate or sequential use in the treatment of thrombotic disorders, wherein suitably amorphous clopidogrel may be provided by a pharmaceutically acceptable preparation substantially as hereinbefore described for inclusion in the product.
The present invention further provides amorphous clopidogrel for use in the manufacture of a medicament for the treatment of thrombotic disorders as


WO 2004/026879 PCT/GB2003/003988
described herein. Again, the amorphous clopidogrel may suitably be present in a pharmaceutically acceptable preparation substantially as hereinbefore described, for use in the manufacture of a medicament for the treatment of thrombotic disorders as described herein.
The present invention also provides a method of treating thrombotic disorders in an animal patient in need of such treatment, which method comprises administering to the animal patient an effective amount of amorphous clopidogrel for treating thrombotic disorders in the animal patient. The amorphous clopidogrel employed in such a method may suitably be present in a pharmaceutically acceptable preparation or composition substantially as hereinbefore described.
Still further provided by way of the present invention are processes for the preparation of amorphous clopidogrel as herein described.
Amorphous clopidogrel according to the present invention is conveniently prepared by a process which constitutes a further feature of the present invention, and which comprises recovering clopidogrel from a solution thereof under conditions whereby an amorphous product is obtained.
The amorphous clopidogrel of the instant invention can be prepared by dissolving a crystalline form of clopidogrel in a suitable solvent or solvent mixture, such as, for example, methanol and / or water, followed by recovery of the material by any suitable means. Techniques which may be employed to recover amorphous clopidogrel from the solution include those wherein the solvent is removed from the solution, preferably rapidly, and the product deposited. Methods involving the use of these procedures which have been found to be satisfactory include spray drying, roller drying, solvent precipitation, rotary evaporation, and freeze drying. Particularly preferred for the practice of the present invention are the methods of spray drying or rotary evaporation.
A preferred process according to the present invention comprises dissolving a first salt of clopidogrel (for example, clopidogrel (-) camphor-10-sulfonate) in crystalline form in a solvent or solvent mixture, converting Ihe first clopidogrel salt (for example, clopidogrel (-) camphor-10-sulfonate) to the free base and

WO 2004/026879 PCT/GB2003/003988
subsequently to a second salt of clopidogrel (for example clopidogrel bisulfate) and recovering the second clopidogrel salt from the solution thereof under conditions whereby an amorphous product is obtained.
There is also provided by the present invention clopidogrel (-) camphor-10-sulfonate in crystalline form, suitably for use as an intermediate in the preparation of amorphous clopidogrel, or a pharmaceutically acceptable salt thereof
Solvents which may be employed in the practice of the present invention will be chosen according to the technique and conditions to be employed, and include water, methanol, ethanol, and the like, including mixtures thereof if desired.
The concentration of crystalline clopidogrel in the solvent is typically in the range of about 1 to 300 mg/ml, preferably about 10 to 200 mg/ml. The solvents may, if desired, be heated as an aid to solubility and solvent removal.
Clopidogrel exhibits sufficient heat stability to withstand spray drying and the like, and accordingly, spray drying is the preferred method of recovery. Spray drying systems may be operated in a known manner to obtain an amorphous product essentially free from crystalline material as well as free from particulate contaminants.
The drying gas employed in a spray drying process according to the present invention can suitably be air, but other drying gases such as, for example, nitrogen, argon and carbon dioxide may be employed. The gas inlet temperature to the spray dryer is chosen according to the solvent employed, but would be, for example, in the range of from about 75°C to about 150°C, preferably in the range of from about 85°C to about 115°C.
Amorphous clopidogrel may also be combined with a number of other materials prior to or after spray drying, or otherwise processed to provide amorphous clopidogrel, which may in turn be further formulated for processing.
The present invention also provides a process of preparing a preparation substantially as hereinbefore described, which process comprises complexing an effective amount of amorphous clopidogrel substantially as hereinbefore

WO 2004/026879 PCT/GB2003/003988
described, with at least a homopolymer or copolymer of N-vinyl pyrrolidone.
Suitably, either or both of amorphous clopidogrel and the homopolymer or copolymer of N-vinyl pyrrolidone is or are present in solution.
When amorphous clopidogrel is present in solution, we prefer to use a suitable organic solvent such as methanol, ethanol, isopropanol, acetone, ethyl acetate or any suitable solvent. When the homopolymer or copolymer of N-vinyl pyrrolidone is in solution, suitable solvents include methanol, ethanol, isopropanol or any other suitable solvent.
When a complex present in a preparation according to the present invention is formed in solution, it is advantageously recovered from the solution for storage or use in solid form. Thus, for example, solvent can be removed from the solution such as by evaporation, to cause the complex to precipitate. Other recovery methods can also be used such as, for example, spray drying. However, care needs to be taken not to expose the complex to temperatures at which amorphous clopidogrel might be degraded.
The present invention will now be further illustrated by the following Figure and Examples, which do not limit the scope of the invention in any way.
Figure 1 shows the powder X-ray diffraction pattern of amorphous clopidogrel prepared according to the present invention.
Example 1
Preparation of Amorphous Clopidogrel Bisulfate
Crystalline Clopidogrel bisulfate Form-2,25g, was stirred in 100ml of methanol to obtain a clear solution. This solution was spray dried in a Lab Plant Spray Drier SD 05 with an inlet temperature of 90°C, outlet temperature of 70°C, compressed air rate of 0.3m3/hr and a feed rate of 8ml/min to obtain 18g of the title product.
The amorphous title product was characterised by powder X-ray diffraction.

WO 2004/026879 PCT/GB2003/003988
Example 2
Preparation of Amorphous Clopidogrel Bisulfate
Crystalline Clopidogrel bisulfate Form-1, 25g, was stirred in 500ml of water to obtain a clear solution. This solution was spray dried in a Lab Plant Spray Drier SD 05 with inlet temperature of 110°C, outlet temperature of 80°C, compressed air rate of 0.3m3/hr and a feed rate of 8ml/min to obtain 19g of the title product.
The amorphous title product was characterised by powder X-ray diffraction.
Example 3
Preparation of Amorphous Clopidogrel Bisulfate
20g of crystalline Clopidogrel bisulfate Form-1 was dissolved in 60ml of methanol under stirring. Methanol was distilled off on a rotary evaporator under vacuum of 1-4 mbar at a temperature in the range of 50-55°C to obtain a foam. The foam was further dried on the rotary evaporator for 2 hours at a temperature in the range of 50-55°C, Imbar vacuum and the product unloaded.
The amorphous title product was characterised by powder X-ray diffraction.
Example 4
Preparation of Amorphous Clopidogrel Bisulfate
20g of crystalline Clopidogrel bisulfate Form-2 was dissolved in 60ml of methanol under stirring. Methanol was distilled off on a rotary evaporator under vacuum of l-4mbar at a temperature in the range of 50-55°C, to obtain a foam. The foam was further dried on the rotary evaporator for 2 hours at a temperature in the range of 50-55°C, Imbar vacuum and the product unloaded.

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The amorphous title product was characterised by powder X-ray diffraction.
Example 5
Preparation of Amorphous Clopidogrel Bisulfate
"
20g of Clopidogrel (-) camphor-10-sulfonate was taken in 100ml of water and 100ml of dichloromethane. To this was added 10% aq. sodium bicarbonate solution and the organic layer was separated. Concentration of the solvent yielded the base, which was dissolved in 100ml of methanol and sulphuric acid 3g was added and the solution spray-dried as in Example 1 to obtain 11.5g of the title product.
The amorphous product was characterised by powder x-ray diffraction.
Example 6
Amorphous Clopidogrel base complex
10g of (+)Clopidogrel was dissolved in 50ml of methanol. To this was added a
solution of 20g of polyvinyl pyrrolidone in 100ml of methanol, and the solvent
was evaporated on a rotary evaporator under vacuum at about 50°C. After
complete removal of the solvent, the residue was further kept under vacuum at
500C for further 2 hours, when the title compound was obtained as a white foamy
solid, which was removed and packed as a free flowing solid, assay 32%. The
solid was characterised by x-ray diffraction.
Example 7
Preparation of a Pharmaceutical Formulation of Amorphous Clopidogrel Bisulfate
A solid oral pharmaceutical formulation according to the present invention can be manufactured by any granulation process known in the art. The following is illustrative of one such process.


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PCT/GB2003/003988



Ingredient Quantity/tablet (mg)
Clopidogrel bisulfate 97.854
Pregelatinised starch 40.000
Microcrystalline cellulose 23.000
Lactose 95.146
Colloidal silicon dioxide 3.000
Stearic acid 6.000
Coating material
Hydroxypropyl methyl cellulose 6.475
Polyethylene glycol — 6000 0.700
Titanium dioxide 0.800
Red oxide of iron 0.025
Methylene chloride q.s.
Isopropyl alcohol q.s.
The amorphous Clopidogrel bisulfate was blended with the excipients and then lubricated with stearic acid. The resulting mixture was then compressed to form tablets and the resulting tablets were film coated.
Pharmaceutical composition prepared according to present invention is a synergistic composition exhibiting surprising results.

WE CLAIM:
1. A process for preparing an amorphous salt of clopidogrel comprising the step of recovering salt of clopidogrel from a solution thereof under conditions in the presence of a solvent or solvent mixture whereby an amorphous product is obtained.
2. A process as claimed in claim 1, wherein the said process comprises dissolving a crystalline form of clopidogrel in a solvent or solvent mixture, followed by recovery of an amorphous salt of clopidogrel.
3. A process as claimed in claim 2, wherein the said process comprises dissolving a first salt of clopidogrel in crystalline form in a solvent or solvent mixture, converting the first clopidogrel salt to the free base and subsequently to a second salt of clopidogrel and recovering the second clopidogrel salt from the solution thereof underconditions whereby an amorphous product is obtained.
4. A process as claimed in claim 3, wherein the first salt is clopidogrel (-) camphor-10-sulfonate and the second salt is clopidogrel bisulfate.
5. A process as claimed in claim 1, wherein recovery is by spray drying or rotary evaporation.
6. A process as claimed in claim 1, wherein the solvent or solvent mixture comprises water and/or methanol.
7. A process as claimed in claim 2, wherein the concentration of crystlline clopidogrel in the solvent or solvent mixture is in the range of 1 to 300 mg/ml.
8. A process as claimed in claim 7, wherein the concentration of crystaUine clopidogrel in the solvent or solvent mixture is in the range of 1 to 200 mg/ml.

9. A pharmaceutical composition comprising an effective amount of a salt of clopidogrel, in amorphous form, essentially free from any crystalline form of clopidogrel, obtained from the process as claimed in claim 1, together with an excipients matrix comprising a1 least a homopolymer or copolymer of N-viny1 pyrrolidone, wherein the said homopolymer or copolymer of N-viny1 pyrrolidone is complexed with the said amorphous pharmaceutically acceptable salt of clopidogrel.
10. A pharmaceutical composition as claimed in claim 9, wherein the said homopolymer or copolymer of N-viny1 pyrrolidone is selected from the group consisting of PVP K-12, PVP K-15, PVP K-25, PVP K-30, PVP K-60, PVP K-90 and PVP K-120.
11. A pharmaceutical composition as claimed in claim 10, wherein the said homopolymer or copolymer of N-vinyl pyrrolidone is PVP K-30.
Dated this 09thday of March, 2005
RAJESHWARI H.
of K& S Partners
Attorney for applicant(s)

Documents:

00179-mumnp-2005-cancelled pages(05-07-2007).pdf

00179-mumnp-2005-claims(granted)-(05-07-2007).doc

00179-mumnp-2005-claims(granted)-(05-07-2007).pdf

00179-mumnp-2005-correspondence(ipo)-(02-01-2008).pdf

00179-mumnp-2005-correspondence1(03-01-2008).pdf

00179-mumnp-2005-correspondence2(16-10-2007).pdf

00179-mumnp-2005-correspondence3(02-05-2008).tif

00179-mumnp-2005-form 1(07-03-2005).pdf

00179-mumnp-2005-form 1(09-03-2005).pdf

00179-mumnp-2005-form 18(14-07-2005).pdf

00179-mumnp-2005-form 2(granted)-(05-07-2007).doc

00179-mumnp-2005-form 2(granted)-(05-07-2007).pdf

00179-mumnp-2005-form 26(05-07-2007)0014.pdf

00179-mumnp-2005-form 26(09-03-2005).pdf

00179-mumnp-2005-form 3(07-03-2005).pdf

00179-mumnp-2005-form 3(21-08-2007).pdf

00179-mumnp-2005-form 5(07-03-2005).pdf

00179-mumnp-2005-form-pct-ipea-409(05-07-2007).pdf

00179-mumnp-2005-form-pct-isa-210(05-07-2007).pdf

abstract1.jpg


Patent Number 213706
Indian Patent Application Number 179/MUMNP/2005
PG Journal Number 42/2008
Publication Date 17-Oct-2008
Grant Date 10-Jan-2008
Date of Filing 09-Mar-2005
Name of Patentee CIPLA LIMITED
Applicant Address 289 BELLASIS ROAD, MUMBAI CENTRAL, MUMBAI,
Inventors:
# Inventor's Name Inventor's Address
1 RAO DHARMARAJ, RAMACHANDRA 204 SHRIJI KRUPA, SWAMINARAYANNAGAR, POKHRAN ROAD#1, THANE 400 601,
2 KANKAN, RAJENDRA NARAYANRAO A-3/5, NBD SICUETY, NSS ROAD, GHATKOPAR, MUMBAI-400 084,
PCT International Classification Number C07D 495/04
PCT International Application Number PCT/GB2003/003988
PCT International Filing date 2003-09-16
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 0221788.3 2002-09-19 GB