Switching to DTG/3TC or continuing B/F/TAF tied to similar virologic efficacy in adults with HIV

Switching to dolutegravir/lamivudine (DTG/3TC) or continuing bictegravir/emtricitabine/tenofovir alafenamide (B/F/TAF) showed comparable virologic efficacy through 96 weeks in adults with HIV infection, according to the DYAD observational, open-label extension (OLE) study presented at IDWeek 2025.

The DYAD trial enrolled 222 adults with HIV who were virologically suppressed (HIV-1 RNA <50 copies/mL), had no prior virologic failure, and were on antiretroviral therapy with B/F/TAF. They were randomized in a 2:1 ratio to either switch to DTG/3TC (n=149) or continue B/F/TAF (n=73) for 48 weeks. Subsequently, 124 and 63 participants, respectively, entered the observational OLE phase of the study.

At 96 weeks, only 2 percent of patients who switched to DTG/3TC and 1 percent of those who continued B/F/TAF had HIV-1 RNA ≥50 copies/mL, the study’s primary endpoint, showing similar virologic efficacy in both groups (adjusted treatment difference, 0.6 percent). [IDWeek 2025, abstract P-348]

More than half of the participants in both groups maintained virologic suppression (HIV-1 RNA <50 copies/mL) at week 96 (66 percent [DTG/3TC] and 71 percent [B/F/TAF]; adjusted treatment difference, -4.8 percent).

However, thirteen patients in the DTG/3TC group and six patients in the B/F/TAF group met the criteria for confirmed virologic failure, with two and one, respectively, showing treatment-emergent resistance.

On the other hand, persistence rates were similarly high in both treatment groups (75 percent [DTG/3TC] and 80 percent [B/F/TAF]).

In terms of adverse events (AEs), drug-related AEs were more prevalent in the DTG/3TC group compared with the B/F/TAF group (28 percent vs 5 percent), leading to seven patients withdrawing from the study in the DTG/3TC group, while none was reported in the B/F/TAF group.

Nausea, fatigue, and diarrhoea were the most commonly reported drug-related AEs in both groups.

With regard to renal and metabolic parameters, no significant differences in creatinine levels, lipid profiles, weight, and BMI were observed between the DTG/3TC and B/F/TAF groups.

“Overall, in the 96-week DYAD observational extension phase, there was no significant difference in virologic efficacy among those switching to DTG/3TC vs continuing B/F/TAF,” said lead author Dr Charlotte-Paige Rolle from Orlando Immunology Center, Orlando, Florida, US.

“These longer-term data reinforced findings from the 48-week analysis and support the use of DTG/3TC as a robust switch option in virologically suppressed adults on contemporary INSTI*-based three-drug regimens,” she added.