Purpose: Antiretroviral regimens containing emtricitabine plus tenofovir disoproxil fumarate might be associated with a lower incidence and severity of lipoatrophy. In this study we compare the effect of proactively switching zidovudine and lamivudine to emtricitabine plus tenofovir disoproxil fumarate on peripheral fat loss with continued lamivudine and zidovudine-based treatment in HIV-1 infected adults also receiving a non-nucleoside reverse transcriptase inhibitor or (boosted) protease inhibitor. In the patients who discontinue the use of zidovudine and switch to emtricitabine and tenofovir disoproxil fumarate we expect to demonstrate a regaining or at least a lack of further loss of peripheral adipose tissue.