Virological Effectiveness of Dolutegravir Plus Darunavir in People with Multi-Drug-Resistant HIV: Data from the PRESTIGIO Registry.

Background: Data on the use of dolutegravir (DTG) plus boosted darunavir (DRV/b) in people with 4-class drug-resistant HIV (4DR-PWH) are limited. This study assessed the virological effectiveness of DTG + DRV/b in this population using real-world data from the PRESTIGIO Registry. Methods: We compared three regimen groups: dual DTG + DRV/b (DODA), DTG + DRV/b plus an additional antiretroviral drug (DODA + Other), and regimens excluding DTG + DRV/b (NO-DODA). Virological failure (VF) was defined as ≥2 HIV-RNA values ≥ 50 copies/mL or 1 ≥ 1000 copies/mL. Mixed-effects logistic regression was used to assess VF, adjusting for antiretroviral therapy (ART) duration, age, number of fully active drugs, sex at birth, and nadir CD4+. Individuals could switch regimens during follow-up. Results: Among 249 4DR-PWH (median follow-up: 8.7 years), 844 ART regimens were analyzed: 72 (8.5%) DODA, 264 (31.3%) DODA + Other, and 508 (60.2%) NO-DODA. Compared to NO-DODA, the odds of VF were 77% and 35.9% lower with DODA and DODA + Other, respectively. Notably, in the DODA group, DTG and DRV/b were fully active in only 63.9% and 47.2% of the cases, respectively. Conclusions: DTG + DRV/b regimens were associated with a significantly lower risk of virological failure, even when drug activity was partial. This strategy remains a valuable option for managing multi-drug-resistant HIV.