Characterization of Genotypic and Phenotypic Changes in HIV-1-Infected Patients with Virologic Failure on an Etravirine-Containing Regimen in the DUET-1 and DUET-2 Clinical Studies

Abstract The randomized, placebo-controlled Phase III DUET studies enrolled treatment-experienced, HIV-1-infected patients. We examined the genotypic and phenotypic changes at endpoint relative to baseline, including the emergence of individual reverse transcriptase (RT) mutations, in patients who received the non-nucleoside reverse transcriptase inhibitor (NNRTI) etravirine and experienced virologic failure by rebound by the time of the Week 96 analysis. Patients received etravirine 200 mg twice-daily in combination with a background regimen containing darunavir/ritonavir, investigator-selected nucleoside reverse transcriptase inhibitors, and optional enfuvirtide. Virologic failure by rebound occurred in 93 (15.5%) etravirine-treated patients (compared with 170 [28.1%] placebo-treated patients). Patients experiencing virologic failure had more baseline antiretroviral resistance and lower activity of the background regimen relative to those not experiencing failure. Emergence of NNRTI resistance-associate...