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

Abstract

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 €130,117.58 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.

Keywords: HIV; antiretroviral therapies; dual therapy; two-drug regimen.