To investigate the presence of natural resistance mutations to entry inhibitors in HIV-1 subtypes B, C, and CRF31_BC strains.
Eighty samples were collected from antiretroviral-na茂ve patients. The gp41 gene from 67 patients and the gp120 gene from 65 patients were partially sequenced. Resistance mutations to entry inhibitors Enfuvirtide, Maraviroc, and Vicriviroc were screened.
ENF resistance-associated mutations of HR1 and HR2 on gp41 were not associated with any subtype. However, the major polymorphisms detected in HR1: N42S, L54M, and A67T were most prevalent in subtype C (p < 0.001). Mutations A316T and R315Q in gp120, which are related to MVC and VCV reduced susceptibility respectively, were predominant in subtype C (p < 0.05).
This study shows that many more resistance-associated mutations to entry inhibitors in ARV-na茂ve patients occur in subtype C compared with subtype B strains. However, further studies will be necessary to elucidate if the differential genetic background of HIV subtypes can affect the efficacy of treatment with entry inhibitors.