Formulation Studies of Extended Release Matrix Tablet of Some Antiviral Drugs

Abstract

Antiviral drug are commonly prescribed for the treatment of Acquired Immunodeficiency Syndrome (AIDS), one of .the most serious disease states worldwide. The antiviral drugs selected for this study are Zidovudine and Nevirapine. They have a short elimination half-life, necessitating multiple doses per day and therefore the development of extended release dosage forms incorporating these drugs was considered beneficial in terms of extending the dosing interval, with the aim of improving patient compliance and subsequent therapeutic outcomes. newlineFormulation approach was to have a composition qualitatively similar to that of the innovator by using different grades of release controlling polymer i.e. Hydroxyl propyl methyl cellulose (HPMC) for extended release matrix tablets. For the solid state characterization of both APIs, different tests were performed like FTIR optical microscopy, powder X-ray diffractometry (XRD), differentials scanning calorimetric (DSC), dynamic vapor absorption (DVS). Stress stability data was also generated. API and excipient compatibility was conducted at different ratios using moist and dry conditions. Samples were kept at 50oC and 40oC/75 % RH and evaluated for impurities newlineFor the Nevirapine ER tablets, QbD based approach was implemented. Initial composition was arrived with different design trials by changing the concentration of HPMC polymer ratio and also grades of HPMC. Wet granulation technique was used for both drugs. Formulation showing desired dissolution profile was finalized and complete characterization like description, identification, assay, content uniformity, and dissolution was done. For the Zidovudine ER tablets, in vivo studies were carried out which show drug release for 20 hrs. newline