FORMULATION AND EVALUATION OF STAVUDINE EXTENDED RELEASE TABLETS

Stavudine is a prescription medicine used to treat AIDS and HIV infection. Stavudine belongs to a group of medications known as nucleoside reverse transcriptase inhibitors (also known as NRTIs). Stavudine is an extremely metabolized drug on oral administration. Due to its sudden metabolism the t1/2 of Stavudine has been decreased to 0.5 hrs which is major limitation for Stavudine as immediate release dosage form. Therefore the present investigation is concerned with the development of Stavudine extended release (ER) tablets by using different hydrophobic and hydrophilic polymers like Ethocel (ethyl cellulose), Methocel (Hydroxy propyl methyl cellulose) polymers in different ratios. Sta vudine along with polymers and other ingredients were directly mixed and compressed by using rotary tablet punching machine (Cadmach). After formulation those tablets were evaluated for weight variation, content uniformity, In-vitro drug release, and stability. Eight combinations having polymers at different proportions were prepared to access their efficacy. Tablets containing 90% ethyl cellulose and 10% hydroxyl propyl methyl cellulose showed superior organoleptic properties and In-vitro drug release studies as compared to other formulations. The kinetic model of the release data indicates that Stavudine release from the tablets followed Korsemayer-Peppas model and release was found to be Case-II transport (polymer swelling). Thus the release from the prepared formulations was found to be diffusion controlled