Work on the tablet formulation in a active substance of antitrombotic effect

Clopidogrel bisulphate is used for decreasing the atherothrombotic events and acute coroner syndrome, but it has quite low bioavaliability (40-50%). It was aimed to increase its bioavailability by designing a controlled release dosage of clopidogrel which is different from available current dosage forms in the market. Initially the UV and IR spectrum of clopidogrel was determined and evaluated in terms of purity and analysing the active substance. The maximum solubility of clopidogrel was determined with the value of 18.8 to 0.4 mg/ml in the solution having a pH 1.2 to 7.4. The amount of excipients for each formulation were determined using fuzzy logic computer program. The physical characteristics (flowing time, angle of repose and compactability) of all formulations were determined experimentally. The release characteristics and profiles were determeined by USP paddle method A and release kinetics were also investigated. The release profiles of commercial formulations were determined and release profiles were compared by f2 similarity test. Two extended release formulations and innovator product (Plavix) were selected and their effectivenesses were compared by vivo tests in rabbits. In in vivo test, platelet numbers, prothrombin time, thrombin time, activated partial thromboplastin time (APTT), coagulation percentage with fibrinogen and collagen/AOP closer times were determined and compared after oral administration. In conclusion, proposed controlled release formulations were found to be an alternative and to be more effective for longer time period than that of the commercial one.