Low Prevalence of HIV-1 Antiretroviral Resistance Among Patients Experiencing Virological Failure on Dolutegravir-Based Regimens: A Prospective Cohort Study in Bunia, Democratic Republic of the Congo

Abstract

The adoption and widespread use of dolutegravir (DTG)-based antiretroviral therapy (ART) are key strategies for achieving global 2030 targets, though emerging resistance threatens long-term success. This study evaluated HIV-1 drug resistance mutations among participants experiencing virological failure in Bunia, Democratic Republic of the Congo (DRC). Over an 11-month period, a prospective cohort study was conducted across 20 healthcare facilities in Bunia, Ituri Province. Targeted genotyping of the HIV-1 pol gene was performed, antiretroviral resistance mutations were identified, and genotypic sensitivity scores (GSSs) were calculated using the Stanford HIV Drug Resistance Database. Virological failure occurred in 12.3% (74/603) of participants, and targeted genotyping of the HIV-1 pol gene was attempted on 53 samples. This subgroup comprised 41 females (55.4%) and 33 males (44.6%), with a median age of 36 years (IQR: 17.0) and a median ART duration of 24 months. Subsubtype A1 predominated (38%), followed by subtypes G (26%) and D (9%); recombinant forms, led by CRF02_AG, accounted for 16%. Mutations associated with resistance to reverse transcriptase inhibitors were detected in 26.4% (14/53) of successfully sequenced samples, compared with 33.9% (18/53) for integrase strand-transfer inhibitors. Overall, GSS analysis revealed that 98% (50/51) of evaluable participants scored 3, whereas only 2% (1/51) scored below 3. This study demonstrates that DTG-based ART remains highly effective in Bunia. To optimize treatment outcomes and support progress toward the UNAIDS 95-95-95 targets, targeted interventions to enhance treatment adherence are urgently warranted.