Decay kinetics of HIV-1-RNA in seminal plasma with dolutegravir/lamivudine versus dolutegravir plus emtricitabine/tenofovir alafenamide in treatment-naive people living with HIV

Abstract

Background: This was a substudy of a Phase IV, randomized clinical trial (ClinicalTrials.gov identifier: NCT04295460) aiming to compare the activity of dolutegravir/lamivudine versus dolutegravir plus tenofovir alafenamide/emtricitabine (DTG+TAF/FTC) in the male genital tract. Methods: Participants were asymptomatic adults without sexually transmitted diseases, treatment-naive people living with HIV (PLWH), with CD4+ T cell counts >200 cells/mm3 and plasma HIV-1-RNA levels >5000 and <500000 copies/mL, randomized (1:1) to DTG+TAF/FTC or dolutegravir/lamivudine. Blood plasma (BP) and seminal plasma (SP) were collected at baseline and Weeks 4, 8, 12 and 24. HIV-1-RNA was measured in BP and SP using the Cobas 6800 system (Roche Diagnostics) with a lower detection limit of 20 copies/mL. The primary efficacy endpoint was the proportion of subjects with undetectable SP HIV-1-RNA at Week 12 by intention-to-treat analysis. Results: Fifteen participants in the DTG+TAF/FTC and 16 in the dolutegravir/lamivudine arms were analysed, with basal SP viral load of 4.81 (4.30-5.43) and 4.76 (4.09-5.23), P=0.469, respectively. At Week 12, only one participant in each treatment arm had a detectable SP HIV-1-RNA (DTG+TAF/FTC, 141 copies/mL; dolutegravir/lamivudine, 61 copies/mL). Based on the estimated means, there was no significant difference in the decay of HIV-1-RNA in both BP and SP over time between the two arms of treatment (F=0.452, P=0.662, and F=1.147, P=0.185, respectively). Conclusions: After 12 weeks of treatment, there were no differences in the percentage of undetectable SP HIV-1-RNA in naive PLWH who started dolutegravir/lamivudine compared with DTG+TAF/FTC.