Real-World Experience with Two-Drug Regimens in HIV-1-Infected Patients Beyond the Indication of Clinical Trials: 48 Weeks' Results

Data on two-drug regimens (2DRs) have shown high efficacy and tolerability in treatment-naive and treatment-experienced HIV-1 patients. Current guidelines recommend 2DRs as alternative to three-drug regimens (3DRs) to reduce long-term drug exposure and costs. Nevertheless, real-world experience with 2DR is limited. This study assessed the use of 2DR in routine clinical practice in a tertiary hospital. A retrospective, observational, descriptive study was performed on the use of dual therapy in adult HIV-1 patients. Individuals on antiretroviral treatment (ART) with dolutegravir plus lamivudine or dolutegravir plus rilpivirine who started 2DR between November 1, 2018, and April 30, 2019, were eligible for our study. Follow-up period was 48 weeks. Overall, 112 patients started 2DR; median age was 51 years and 88.4% were men. Most patients (97.3%) were treatment experienced before dual therapy, with 9.6 +/- 8.0 years of prior ART on average. Around 96.4% of patients were virologically suppressed before 2DR. Most common reasons to start dual therapy were treatment simplification (49.5%), avoidance of long-term toxicities (21.1%), and intolerance to previous ART (18.3%). The main regimen used in dual therapy was dolutegravir plus lamivudine (98.2%). Only eight patients discontinued dual therapy; the main reason for discontinuation was toxicity. All patients who did not discontinue 2DR were virologically suppressed at week 48. ART simplification saved euro130,117.58 during the study period. In our cohort, dual therapy was mainly used for virologically suppressed patients, before availability of the single-tablet 2DR. Switching to a 2DR may be a key option for treatment simplification and avoidance of long-term toxicities. Furthermore, 2DR could provide a more cost-effective alternative to 3DR.