Background and importance Dual antiretroviral therapy (DAT) is currently used as initial treatment in naïve patients or as a maintenance therapy in those who are virologically suppressed. The simplification of antiretroviral regimens is associated with a reduction in treatment toxicities and costs and an adherence improvement. However, there are a lack of studies reporting data on DAT effectiveness beyond clinical trials.

Aim and objectives To assess the durability and reasons for discontinuation of DAT in HIV-infected patients.

Material and methods This was a retrospective, cohort study. Adult HIV-infected patients who started a treatment with DAT between 2015 and 2019 in a general hospital were included. Sociodemographic data, HIV-1 RNA copies at baseline and treatment data (DAT combination, previous treatment, time to discontinuation and reason for discontinuation) were collected from clinical records. Treatment durability was assessed using the Kaplan-Meier analysis up to 48 weeks.

Results Fifty-one patients were included: 31 patients were male, mean age was 49±11 years. Mean time from HIV diagnosis was 16.2±9.1 years, 20 patients had a previous classification Centers for Disease Control and Prevention (CDC) stage C and 15 had a history of intravenous drug use. Thirty-six patients were previously treated with a three-drug regimen, 8 with a DAT, 5 with an antiretroviral monotherapy and 2 were treatment-naïve. Thirty-seven patients were virologically suppressed at baseline. DAT combinations were: integrase inhibitor (INI) plus nucleoside reverse transcriptase inhibitor (NRTI) or non-nucleoside reverse transcriptase inhibitors (NNRTI) (n=29), boosted protease inhibitor (PI/b) plus NRTI or NNRTI (n=15) and INI plus PI/b (n=7). Thirty-nine patients maintained DAT at 48 weeks and mean treatment duration was 40.5±14.8 weeks. The reasons for discontinuation were: lack of effectiveness (n=1), treatment simplification (less-pills regimen) (n=3), abandonment (n=2), drug-drug interactions (n=2), kidney failure (n=1), death (n=1) and follow-up losses (n=2).

Conclusion and relevance A broad spectrum of DAT combinations were used according to patients’ characteristics. Although 14 patients were not at virological suppression at baseline, DAT showed a high durability at 48 weeks and only 2 patients discontinued due to lack of effectiveness or toxicity.

Conflict of interest No conflict of interest