Breakthrough HIV study reveals potential for twice-yearly treatment dosing

ViiV Healthcare has released positive 12-month results from its phase IIb EMBRACE study. The trial tested lotivibart, an experimental HIV treatment, in combination with long-acting cabotegravir (CAB LA). Data presented at the 33rd Conference on Retroviruses and Opportunistic Infections (CROI 2026) showed strong viral suppression rates and good tolerability.

The findings suggest potential for less frequent dosing, with further research now exploring a twice-yearly treatment schedule.

The study involved adults with HIV on stable therapy. Participants received lotivibart either intravenously (IV) every four months or subcutaneously (SC), alongside monthly injections of CAB LA. After a year, 94% of those in the IV group maintained viral suppression, compared to 82% in the SC group. The standard of care group, meanwhile, achieved an 88% suppression rate.

Virologic failure rates remained low across all groups: 4% in the IV arm, 6% in the SC arm, and 4% in the standard of care group. Tolerability was generally high, though infusion-site reactions differed. No severe reactions occurred in the IV group, while 16% of the SC group experienced grade 3-4 reactions.

Kimberly Smith, Head of Research & Development at ViiV Healthcare, highlighted the results as encouraging. She noted that the data support further evaluation of lotivibart on a twice-yearly dosing schedule. The next phase of the study will now test this extended interval for IV administration.

These findings reinforce lotivibart's potential as an ultra long-acting treatment, with dosing possible every four months or longer. The drug remains in early-stage development, and no public trials currently combine it with CAB LA for semi-annual IV use in HIV patients.

The phase IIb EMBRACE study demonstrates lotivibart's promise in reducing dosing frequency while maintaining high viral suppression. With fewer adverse events in the IV group and strong efficacy, the treatment could offer a more convenient option for people living with HIV. Further research will determine whether twice-yearly dosing becomes a viable alternative to current regimens.