Investigators found they could reduce the once-daily (OD) dosing of the
antiretroviral therapy (ART) bictegravir/emtricitabine/tenofovir alafenamide (BIC/FTC/TAF; Biktarvy; Gilead) from OD up to 3 weeks safely and effectively over a nearly a year time period.1
“In virally suppressed [people with HIV] on [BIC/FTC/TAF] BETAF OD, the strategy of reducing the BETAF OD dose to 3W, 2W, or 1W for 48 weeks was safe, well tolerated, and effective as compared with continuing OD,” the investigators wrote.1 The findings were presented as a poster at CROI 2025, held March 9-12, in San Francisco, California.
BIC/FTC/TAF in the small pilot study encompassed 40 participants with well-controlled HIV. Individuals were randomized (n = 10 per arm) to: OD, 3W (Mon-Wed-Fri), 2W (Tue-Fri), or 1W (Wed) with visits at baseline and 4, 12, 24, 36, and 48 weeks.1
The investigators had strict criteria for dissolution of both the arms and individual participants.
“Individuals with viral failure (confirmed VL ≥50 c/mL) underwent genotypic resistance testing and were switched to OD up to 48 weeks,” the investigators wrote. “We measured ultrasensitive VL; total, defective, and intact HIV reservoir (IPDA); CD4 and CD8 cells; hsCRP and IL-6; and plasma and intracellular trough drug levels at baseline, 12, and 48 weeks. The stopping rule was >30% viral failure in any of the dose reduction arms.”1
What You Need to Know
Investigators found that reducing the daily dose of BIC/FTC/TAF to as little as three times per week (3W), twice per week (2W), or once per week (1W) over 48 weeks was generally safe, well-tolerated, and effective in maintaining viral suppression in people with HIV (PWH).
Only three participants experienced viral rebound (two from the 1W group and one from the 3W group). However, no resistance mutations developed, and viral suppression was restored when they returned to once-daily (OD) dosing.
The study had a strict protocol for stopping dose reduction if more than 30% of participants in a given group experienced viral failure.
In terms of viral rebound, 3 participants experienced the phenomenon, with 2 of them coming from the 1-week cohort and 1 coming from the 3-week cohort. The investigators reported no resistance mutations developed, and viral suppression was restored after they went back to OD dosing.1
"There were no significant differences in ultrasensitive VL, HIV reservoir, CD4 or CD8 cells, and hsCRP or IL-6 among arms. Although trough plasma and intracellular drug levels significantly decreased in 3W, 2W, and 1W relative to OD at 12 and 48 weeks, mean trough levels at 12 and 48 weeks in 3W and 2W, but not in 1W, were generally above the known inhibitory concentrations," the investigators wrote.
FDA approved the Gilead ART back in February 2018. At the time of the approval, the company said the following in its press release: “Biktarvy combines the novel, unboosted integrase strand transfer inhibitor (INSTI) bictegravir, with the demonstrated safety and efficacy profile of the Descovy (FTC/TAF) dual nucleoside reverse transcriptase inhibitor backbone, and is the smallest INSTI-based triple-therapy STR available.”2
References
1. Chivite I, et al. Safety, Tolerability, and Efficacy of a BIC/FTC/TAF Dose Reduction Strategy. Poster #659 presented at CROI 2025. March 9-12, 2025, San Francisco, California.
2. Rosa K.FDA Approves Bictegravir for HIV-1. Contagion. February 7, 2018. https://www.contagionlive.com/view/fda-approves-bictegravir-for-hiv
