Efficacy and safety of darunavir/ritonavir plus etravirine dual regimen in antiretroviral therapy-experienced patients : a multicenter clinical experience

Objectives: To assess the outcome of a dual regimen combining darunavir/ritonavir plus etravirine in a cohort of antiretroviral therapy (ART)-experienced patients. Methods: A retrospective analysis was performed on all ART-experienced patients starting a darunavir/ritonavir plus etravirine regimen at the 3 clinics. Patients were stratified according to HIV RNA detectability (≥40 copies/mL) at baseline. Two efficacy endpoints were evaluated by Kaplan-Meier and Cox multivariable models: virological failure (confirmed HIV RNA ≥40 copies/mL after 6 months) and therapeutic failure (including virological failure and treatment discontinuation for any reason). Results: Sixty-eight patients were included in the study. They had a median of 10.8 years on ART and 5 previous ART regimens; 61.3% showed primary protease inhibitor (PI) mutations and 70% showed previous non-nucleoside reverse transcriptase inhibitor (NNRTI) exposure. HIV RNA was detectable in 34 (50%) patients. The median observation period was 21 (interquartile range [IQR], 11.9-25.1) months. After 24 months, 75.1% of the patients were still on the study regimen and 88.8% remained free from virological failure. Although a higher therapeutic failure rate was reported in patients with detectable viremia at baseline, only the immunological status revealed an independent predictive role. No differences in virological failure were observed according to HIV RNA detectability at baseline; a higher number of previous ART regimens was the only predictor. Discontinuation due to adverse events occurred in 5.9%. Conclusions: Darunavir/ritonavir plus etravirine regimen proved virological efficacy and safety in heavily pretreated patients with a high rate of virological success, even in patients who switched during virological failure.