Formulation and Optimization of Controlled Porosity Osmotic Pump Tablets of Lamivudine using Sodium Chloride as Osmogen for the Treatment of AIDS

Abstract

The present study was undertaken to develop controlled porosity osmotic pump tablets of lamivudine a nucleoside reverse transcriptase inhibitor for the treatment of acquired immune deficiency syndrome (AIDS). The tablets were prepared by wet granulation method using HPMC E5LV, and osmogen was prinicipal ingredients a dose of 300 mg once daily. The coating solution of core tablets were prepared by using cellulose acetate, poly ethylene glycol of different grades, sorbitol and acetone to quantity sufficient for different batches. The prepared tablets were evaluated for pre compression parameters, post compression parameters, in vitro drug release study and scanning electron microscopy study. Among developed formulations LS4 batch show 98.26% drug release in 12 hrs. The in vitro release kinetics were analyzed for different batches by different pharmacokinetic models such as zero order, first order, Higuchi, Korsmeyer Peppas and Hixon Crowell model. The results of optimized formulation follow Higuchi kinetics and which is independent of the pH and agitation intensity. Short term stability study (at 40 ± 2°C/75 ± 5% RH for three months) on the best formulation indicated that there was no significant changes in thickness, friability, weight variation, drug content and in vitro drug release.