Comparative effectiveness of antiretroviral drug classes for the treatment of HIV infection in patients with high viral loads: a multicentre retrospective cohort study

Objectives We aimed to compare the effectiveness of antiretroviral therapy (ART) classes for achieving HIV RNA suppression to < 50 HIV-1 RNA copies/mL within 6 months of initiation with high viral loads (VLs). Secondary objectives were to compare viral suppression (VS) at 12 weeks and 12 months, partial HIV RNA suppression to < 200 copies/mL, time to VS, time to rebound, and change in CD4 cell count. Methods This was a multicentre, retrospective, observational study. Adult patients were included if they initiated ART between January 2005 and December 2016 with a VL >= 100 000 copies/mL. Results There were 220 patients included in the study. The median VL was 252 919 [interquartile range (IQR) 149 472-500 000] copies/mL. Nonnucleoside reverse transcriptase inhibitor (NNRTI) recipients were more likely to achieve VS by 6 months compared to those initiating ART containing protease inhibitors (PIs) [75.4%vs. 44.1%, respectively; odds ratio (OR) 3.34; 95% confidence interval (CI) 1.62-6.90] or integrase strand transfer inhibitors (INSTIs) (75.4%vs. 55.8%, respectively; OR 2.40; 95% CI 1.03-5.58). VS at 12 weeks was more frequent with INSTI-containing regimens than with PIs (28.9%vs. 9.0%, respectively; OR 4.10; 95% CI 1.69-9.92). VS at 12 months did not significantly differ between treatment regimens. Median time to complete VS for INSTI, PI and NNRTI recipients was 22.3 (95% CI 13.4-33), 30.1 (95% CI 25-36) and 19.9 (95% CI 16-22.3) weeks, respectively. There were no significant differences in time to viral rebound or change in CD4 cell counts. Conclusions Patients with high VLs initiated on NNRTIs were more likely to achieve VS by 6 months on ART compared to INSTI and PI recipients.