A clinical trial of Gilead Sciences' lenacapavir, a twice-yearly injectable HIV prevention drug, has shown 100% efficacy in preventing HIV infections among adolescent girls and young women in South Africa and Uganda.

The results from the PURPOSE 1 study, which enrolled over 5,300 cisgender participants aged 16-26, demonstrated that lenacapavir was superior to the current standard of care, daily oral Truvada, for pre-exposure prophylaxis (PrEP).

An independent data and safety monitoring board (DSMB) reviewed the trial data and found the lenacapavir regimen to be safe and highly effective, with no infections observed among participants who received the injectable drug. These findings represent a significant advancement in HIV prevention, as lenacapavir is the first PrEP candidate to show 100% efficacy in a Phase 3 clinical trial.

HIV prevention advocates have welcomed the results, emphasizing the potential of long-acting injectables like lenacapavir to improve adherence, increase access, and reduce strain on healthcare systems.

Mitchell Warren, the executive director of AVAC, stated, "We expect to see a timeline that takes into account a full analysis of PURPOSE 1 data and the coming data from PURPOSE 2 from Gilead as soon as possible, and we urge regulatory agencies to prepare to fast track regulatory review".

Nandisile Sikwana, the Regional Stakeholder Engagement Manager for AVAC and a member of the PURPOSE 1 Global Community Advisory Group, expressed excitement about the results and their potential impact for women in Africa.

Sikwana emphasized the importance of accelerating the planning for lenacapavir's rollout, even as the full data from the study, including adherence data for the oral PrEP comparator, are awaited.

A companion trial, PURPOSE 2, is currently underway in several countries, evaluating twice-yearly lenacapavir for PrEP among cisgender men who have sex with men, transgender women, transgender men, and gender non-binary people.