Formulation Development and Comparative Study of Clopidogrel Bisulfate Matrix Formulations

The objective of this study was to design matrix tablets for oral sustained release of clopidogrel bisulfate and to investigate the sustained release behavior of the matrix tablets. Matrices were prepared by direct compression technique, melt method and microencapsulation using sodium carboxymethylcellulose, carnuba wax and ethyl cellulose as a release retardant. The FT-IR analysis indicated the stability and compatibility of drug with excipients. The formulation was optimized on the basis of acceptable tablet properties and invitro drug release. The resulting formulations produced tablets with optimum hardness, uniform thickness, consistent weight uniformity and low friability. The results of dissolution studies indicated that formulations F2 batch exhibited good drug release pattern to provide sufficient concentration for achieving satisfactory therapeutic value for extended period of time. The drug release from F2 formulation was sustained upto 12 hrs. Tablet Fitting in-vitro drug release data from optimized matrix formulation to Korsmeyer Pappas model equation indicated that diffusion and erosion could be mechanism of drug release. Matrix tablet F2 showed no change in physical appearance, drug content after storage 40°C, 75% RH for 3 months.