HIV-1 viral decay in blood and semen in antiretroviral-naïve adults initiating dolutegravir/lamivudine versus bictegravir/emtricitabine/tenofovir alafenamide

Abstract

While coformulated dolutegravir and lamivudine (DTG/3TC) is recommended as the first-line antiretroviral therapy (ART), the data on the viral decay in seminal plasma (SP) and blood plasma (BP), as well as changes in inflammatory biomarkers in BP, remain limited among antiretroviral-naïve people with HIV (PWH) receiving DTG/3TC. We conducted a prospective observational cohort study to compare the impact of DTG/3TC vs bictegravir/emtricitabine/tenofovir alafenamide (BIC/FTC/TAF) on viral decay kinetics and changes of inflammatory biomarkers in antiretroviral-naïve PWH. Newly diagnosed PWH who initiated BIC/FTC/TAF (n=57) or DTG/3TC (n=43) were enrolled. BP and SP were collected at 0, 4, 12, 24, and 48 weeks after ART initiation. The primary endpoint was viral suppression of HIV-1 in BP and SP at week 48. Secondary endpoints included changes of HIV-1 DNA levels and inflammatory biomarkers over the 48-week follow-up. Overall, 96 (96.0%) completed the 48-week follow-up (DTG/3TC, n=40; BIC/FTC/TAF, n=56). Viral suppression rates in BP and SP were comparable between BIC/FTC/TAF and DTG/3TC group in per-protocol analyses at week 48 (BP, 96.4% vs 100%, p=0.519; SP, 100% vs 100%, p>0.999). Both regimens demonstrated similar effectiveness in reducing HIV-1 RNA levels in BP (3.0 vs 3.1 log10 copies/mL) and SP (0.9 vs 1.2 log10 copies/mL). There were no statistically significant differences in the reductions of HIV-1 DNA levels and changes of inflammatory biomarkers over the 48-week follow-up. These findings suggested comparable effectiveness of DTG/3TC vs BIC/FTC/TAF in achieving viral suppression in BP and SP and similar changes of inflammatory biomarkers in BP.