Low-frequency drug-resistant HIV-1 and risk of virological failure to first-line NNRTI-based ART: a multicohort European case–control study using centralized ultrasensitive 454 pyrosequencing. Journal of Antimicrobial Chemotherapy
Cozzi-Lepri et al. investigated the impact of pre-existing minority drug-resistant HIV-1 variants (MV) on the virological outcomes of first-line NNRTI- (i.e. nevirapine or efavirenz) containing antiretroviral treatment. They found that detection of at least one MV conferring resistance to reverse transcriptase inhibitors (RTIs) was associated with a >2-fold increased risk of virological failure, regardless of the NRTI backbone started or whether nevirapine or efavirenz was commenced. There was a direct dose-effect relationship between the mutational load of MVs and risk of viral failure.
The study results suggests that ultrasensitive HIV-1 genotyping could have a role in improving the outcomes of ART including NNRTIs.