A3 Genetic analysis and natural polymorphisms in HIV-1 gp41 isolates from Maputo, Mozambique

Enfuvirtide is an HIV fusion inhibitor that prevents fusogenic conformation and inhibits viral entry into host cells. Resistance to Enfuvirtide is conferred by mutations occurring in the HR1 region of HIV gp41, involving residues 36–45. Mozambique, a sub-Saharan country with an HIV prevalence of 11.5%, provides first line and second line HAART based treatment. In resource-poor settings such as Mozambique the lack of adequate infrastructure, high costs of viral load tests and the availability of salvage treatment has hindered the intended objective of monitoring HIV treatment, suggesting an important concern regarding the development of drug resistance. The general aim of this study was to evaluate natural occurring polymorphisms and resistance-associated mutations in the gp41 region of HIV-1 isolates from Mozambique. The study included 78 patients naive to ARV treatment and 28 patients failing first line regimen, recruited from the Alto Mae Health Centre in Maputo. The gp41 gene from 103 patients was sequenced and resistance associated mutations for Enfuvirtide were screened. Subtype analysis revealed that 93% sequences were classified as subtype C, 2% as subtype G, 1% as subtype A1, and the other 4% as mosaic recombinant forms. No Enfuvirtide resistance associated mutations in HR1 of gp41 were detected. The major polymorphisms in the HR1 were: N42S, L54M, A67T, and V72I. This study suggests that this new class of antiviral drug may be effective as a salvage therapy in patients failing first line regimens in Mozambique. However further phenotypic studies are required to determine the clinical relevance of these polymorphisms detected in this study.