DESIGN, IN VITRO AND IN VIVO EVALUATION OF QUETIAPINE FUMARATE EXTENDED RELEASE TABLETS

Abstract

The present investigation reports the design and evaluation of extended release film-coated matrix tablets of Quetiapine Fumarate to treat schizophrenia using different polymers mainly Carboxy methyl ethyl cellulose and Ethyl cellulose in combination by wet granulation method. The tablets were subjected to thickness, weight variation test, drug content, hardness, friability, in vitro and in vivo release studies. The film coated tablet formulations of various batches (50 mg, 150mg, 200 mg, 300mg and 400 mg) showed acceptable physicochemical properties. Optimized formulations were selected from each batch was based on the evaluation parameters and drug release kinetics. The FTIR & DSC studies indicated absence of any interaction between Quetiapine Fumarate and polymers. The optimized  formulations follows zero order release kinetics and showed non-Fickian (anomalous) release, coupled diffusion, and polymer matrix relaxation, 0.45 < n < 0.89. The innovator product Seroquel XR tablets in different strengths shown to be followed first order release kinetics. From the release kinetic study it can be concluded that the drug release pattern of optimized formulations was controlled manner for 24 hours. The optimized formulation of C6 (200mg) was evaluated for its bioavailability compared with pure drug as reference standard.  In vivo studies were carried out for 200mg tablets and the values of C_max and t_max clearly indicated that the drug release was controlled and maintained constant plasma concentration upto 24 hours after oral administration in comparison with pure drug. The results suggest that the developed extended-release tablets of Quetiapine Fumerate could perform therapeutically better than available dosage forms in the market.