Human immunodeficiency virus-1 drug resistance patterns among adult patients failing second-line protease inhibitor-containing regimens in Namibia, 2010-2015

Three hundred sixty-six adult patients in Namibia with second- line virologic failures were evaluated for human immunodeficiency virus drug-resistant (HIVDR) mutations. Less than half (41.5%) harbored =1 HIVDR mutations to standardized second-line antiretroviral therapy (ART) regimen. Optimizing adherence, viral load monitoring, and genotyping are critical to prevent emergence of resistance, as well as unnecessary switching to costly third-line ART regimens.