Switching Tenofovir/Emtricitabine/Efavirenz to Tenofovir/Emtricitabine/Rilpivirine Versus Continuing Tenofovir/Emtricitabine/Efavirenz in HIV1-infected Patients With Complete Virological Suppression

According to the Thai National Guidelines for Treatment of HIV/AIDS 2014, the recommended first line ART (Anti-retroviral therapy) regimen was 2 NRTIs (nucleoside reverse transcriptase inhibitors) backbone, which are TDF (Tenofovir) and FTC (Emtricitabine); plus 1 NNRTI (non-nucleoside reverse transcriptase inhibitor), which is EFV (Efavirenz), with RPV (Rilpivirine) as an alternative in this class of drug.

Most of the randomized-controlled studies, including ECHO (Rilpivirine versus efavirenz with tenofovir and emtricitabine in treatment-naive adults infected with HIV-1) and THRIVE (Rilpivirine versus efavirenz with two background nucleoside or nucleotide reverse transcriptase inhibitors in treatment-naive adults infected with HIV-1), the major trials about RPV, showed the non-inferiority in efficacy of RPV compared with that of EFV in treatment-naive cases with blood HIV viral load less than 500,000 copies/mL. But there were not many trials focusing on changing the ART-regimens from other NRTI to RPV in patients who currently on another ART, especially in randomized-controlled design. There were some studies comparing continuing current regimens versus changing to Rilpivirine-based regimens, but they didn't exclusively select the homogeneous drug components. In Thailand, study of changing to Rilpivirine-based regimens was primarily designed to evaluate the adverse outcome about dyslipidemia, whereas efficacy was a secondary outcome. Most studies, the concerned adverse effects of dyslipidemia and neurological symptoms were better in RPV-based than EFV-based regimen. Finally, the cost-effectiveness and universal coverage are also the benefit of RPV over EFV in term of economics.

Therefore, we design this study to evaluate the efficacy; in term of non-inferiority, of the newer, safer, and cheaper drug, Rilpivirine, to Efavirenz, the general-use drug with acceptable efficacy, in the virological-suppressed patients currently on ART. Besides, we also assess the adverse outcomes and factors associated with successful or failure of treatment. In addition, we can have more backup data in term of national economics.