SIMULTANEOUS DETERMINATION OF LAMIVUDINE, TENOFOVIR AND EFAVIRENZ IN LAMIVUDINE, TENOFOVIR DISPROPOXIL FUMARATE AND EFAVIRENZ TABLETS BY STABILITY INDICATING ISOCRATIC RP-HPLC METHOD WITH PDA DETECTOR

A simple fast, accurate, precise and cost effective isocratic RP-HPLC method is developed for simultaneous determination of Lamivudine, Tenofovir and Efavirenz in tablet formulation. Lamivudine, Tenofovir and Efavirenz are considered as a very potent regimen in therapy-naive patients and therefore, it is recommended as first-line therapy. It is indicated for the treatment of human immunodeficiency virus-1 (HIV-1) infection in adults and adolescents with virologic suppression to HIV-1 RNA levels of < 50 copies/ml on their current combination antiretroviral therapy for more than three months. Patients must not have experienced virological failure on any prior antiretroviral therapy. The retention times of Lamivudine, Tenofovir and Efavirenz were found to be 2.3, 3.6 and 13.6 minutes respectively. The method was linear over the range of 25 to 45 ppm with r2 = 0.999 for Lamivudine, 25 to 45 ppm with r2 = 0.999 for Tenofovir and 50 to 90 ppm with r2 = 0.999 for Efavirenz. Mean recovery for Lamivudine Tenofovir and Efavirenz were 100.5, 99.4 and 99.9 respectively. The method found simple, accurate, precise, and linear over the given range, rugged and robust.