Effectiveness,Safety,and Costs of a Treatment Switch to Dolutegravir Plus Rilpivirine Dual Therapy in Treatment-Experienced HIV Patients

Background: Evidence about the use of dolutegravir (DTG) and rilpivirine (RPV) as an antiretroviral therapy (ART) in treatment-experienced patients is scarce. Objective: To explore the effectiveness, safety, and costs of switching to a DTG plus RPV regimen in this population. Methods: This observational, prospective study included all treatment-experienced patients who switched to DTG plus RPV between November 2014 and July 2016. Patients were excluded if resistance mutations to integrase inhibitors or RPV were found. The effectiveness endpoint was the proportion of patients who achieved virological suppression (viral load [VL] <50 copies/mL) at week 48 (W48). Safety (incidence of adverse events leading to discontinuation and laboratory abnormalities), adherence, and costs were analyzed. Results: A total of 35 patients were included, and 91.4% were virologically suppressed at baseline. Patients were treated with ART for a median of 14 years (interquartile range = 7-20). At W48, 91.4% of patients were virologically suppressed (95% CI = 77.0-98.2). Two of the 3 patients not suppressed at baseline achieved undetectable VL at W48, and 2 patients discontinued DTG plus RPV (intolerance and a drug-drug interaction). None of the virologically suppressed patients at baseline showed virological rebound through W48. There were no significant changes in lipid, liver, and renal profiles. The proportion of patients with an ART adherence >90% increased from 65.6% to 93.8% (P = 0.004). The annual per-patient ART costs dropped by €665 (P = 0.265). Conclusions: Switching to DTG plus RPV seems to be an effective and safe strategy. Significant improvements in patients’ adherence and costs were achieved.