Abstract

DEVELOPMENT AND INVITRO EVALUATION OF FLOATING DRUG DELIVERY SYSTEM: RITONAVIR

Sunil Firangi* and Dr. S. N. Hiremath

.

Abstract

The drug Ritonavir protease inhibitor widely prescribed as antiviral drug used for the treatment of HIV/AIDS, practically insoluble in water and aqueous fluids and as such it possesses challenging problems in its formulation and development. This work is an attempt to increase the therapeutic efficacy, reduction of the frequency of dose, improvement of bioavailability and patient compliance by designing the controlled release floating drug delivery system of Ritonavir and enhancement in gastric retention time (GRT), tablets were prepared by wet granulation technique by using different grades of HPMC by using PVP K30, Magnesium state, talc, sodium bicarbonate, citric acid, lactose xanthan gum, sodium alginate & Cross carmellous sodium. The prepared tablets were subjected to post compressional parameters such as hardness, weight variation, thickness, diameter, drug content, lag time, buoyancy time, invitro dissolution studies and stability studies. In all the formulations, hardness test indicated good mechanical resistance. Sodium bicarbonate was added as a gas generating agent, induced carbon dioxide generating in presence of 0.1N HCl as dissolution medium. The combination of sodium bicarbonate & citric acid provided desired floating ability and therefore this combination was selected for the formulation. The obtained results revealed that, release of drug was by mixed order kinetics & invitro release data were also subjected to Higuchi’s equation, the r values of all the formulations were 0.9526 and above which indicates that the drug release was by Higuchi’s mechanism. The formulations were also treated to Peppa’s plots, found fairly linear and the regression values of all the formulations indicating a dissolution behavior controlled by Non Fickain Diffusion. The stability studies were conducted as per ICH guidelines were found stable. From these studies it can be concluded that, the formulation retained for longer periods of time in the stomach and provides controlled release of the drug. Hence improve the therapeutic effect of the drug by increasing its bioavailability.

Keywords: Ritonavir, GRT, HPMC, floating drug delivery system.