Pan-Resistant HIV-1 Drug Resistance Among Highly Treated Patients with Virological Failure on Dolutegravir-Based Antiretroviral Therapy in Zimbabwe

The HIV-1 epidemic continues to challenge global public health, especially in sub-Saharan Africa. The rise in drug-resistant viruses, particularly pan-resistant strains, threatens treatment effectiveness, hindering progress toward UNAIDS viral suppression goals. This is critical in low-to-middle income countries (LMICs) like Zimbabwe, where treatment options and access to drug resistance testing are limited. This cross-sectional study analyzed 102 genotypes from patients with HIV-1 RNA ≥ 1000 copies/mL after at least 6 months on a dolutegravir (DTG)-based ART. HIV-1 genotyping and drug resistance interpretation were performed using the Stanford HIV Drug Resistance Database. Overall, 62% of genotypes harbored at least one drug resistance mutation, with 27% showing integrase strand transfer inhibitor (INSTI)-associated mutations. High-level resistance to DTG and cabotegravir was found in 14% and 23% of integrase sequences, respectively, primarily driven by G118R and E138K/T mutations. Pan-resistance was observed in 18% of complete genotypes, with one case of four class resistance. These results highlight the emergence of INSTI resistance in LMICs. The study underscores the urgent need for enhanced HIV drug resistance testing, continuous surveillance, and strategic optimization of ART regimens in resource-constrained settings to ensure effective HIV management.