Geographic and temporal trends of transmitted HIV-1 drug resistance among antiretroviral-naïve subjects screening for two clinical trials in North America and Western Europe.

AbstractPurpose: To determine the prevalence of transmitted drug resistance (TDR) in antiretroviral (ARV)-naive HIV-1-infected subjects who were screened for two clinical trials by geographic region and time. Methods: Studies M03-613 and M05-730 screened ARV-naive subjects in 2004 and 2005–2006, respectively. Screening drug resistance genotype assays were performed using population sequencing, and prevalence of drug resistance mutations (DRMs) was assessed at 39 amino acid positions in HIV-1 protease and reverse transcriptase (RT) and compared between geographic regions and calendar years. Results: In 913 subjects, the prevalence of DRMs was higher in North America than in Western Europe, including any DRM (13.6% vs. 6.8%, p < .001), non-nucleoside reverse transcriptase inhibitor (NNRTI) DRMs (7.3% vs. 3.2%, p = .006), protease inhibitor (PI) DRMs (3.6% vs. 0.8%, p = .004), and nucleoside reverse transcriptase inhibitor (NRTI) DRMs (6.1% vs. 3.8%, p = ns). The prevalence of TDR to NNRTIs was higher compar...