FORMULATION AND EVALUATION OF RAFT FORMING TABLETS OF LAMIVUDINE

Damineni Saritha*, Sana Kazmi, Anupama Koneru and Penjuri Subhash Chandra Bose

ABSTRACT

The aim of the current project was to formulate and evaluate raft forming tablets containing lamivudine as an API. It is a nucleoside reverse transcriptase inhibitor (NRTI), belonging to the class of organic compounds known as 3’-thia pyrimidine nucleosides. It is an anti-retro viral medication used in the treatment and prevention of HIV/AIDS and chronic Hepatitis B. Raft forming tablets were developed to prolong the gastric residence time, increase drug absorption, patient compliance and to decrease the dosing frequency thus decrease the risk of drug resistance and toxicity. Lamivudine tablets were prepared by direct compression method using various polymers such as HPMC, luctoman, sodium alginate, carbopol. In order to study the interaction between drug and selected excipients FT-IR and DSC studies were carried out. Fourteen different formulations of lamivudine were prepared using different ratios of polymers. The formulations formed were examined for hardness, thickness, friability, weight variation, drug content uniformity, % cumulative drug release, in-vitro buoyancy studies, raft strength etc. The formulation FLS1 showed highest percentage drug release for a prolonged period of 8 hrs. The drug release mechanism of the optimized formulation was studied by fitting the acquired drug release data into various kinetic models. The release profile was found to be best fitted in zero order model with an R2 value of 0.998. The n value for the Korsmeyer- peppas model was found to be >0.89, thus declaring that the drug release mechanism followed was super case II transport. Stability studies were performed on FLS1 for a period of 3 months and was found to be stable.

Keywords: lamivudine, RDDS, raft strength, buoyancy studies.