The injection, requiring a booster every six months, offers a more convenient alternative to daily oral HIV pre-exposure prophylaxis (PrEP) like Truvada.

Astrid Berner-Rodoreda from University Hospital Heidelberg called lenacapavir a breakthrough, noting that being vaccinated twice a year is much more convenient than taking a daily pill.
She also said that injections are less stigmatizing and easier to hide, particularly in countries heavily affected by HIV.

The "Purpose 2" study, like its predecessor "Purpose 1," was prematurely concluded due to promising results, enabling all participants to access the drug.

Gilead, the manufacturer, plans to seek approval for lenacapavir as a preventive HIV treatment in multiple countries, with a focus on making it accessible in low-income regions.

The drug inhibits the HIV virus at multiple stages of its lifecycle and is already approved in the European Union for treating existing infections.

While lenacapavir treatment costs about $42,000 per year in the United States, its affordability in poorer countries remains a challenge, Berner-Rodoreda said.

Berner-Rodoreda emphasized the importance of ensuring access to the drug in regions like sub-Saharan Africa, where the need is most urgent.

However, concerns about drug resistance arise, as the active substance can remain in the body for up to a year after stopping the vaccine, potentially promoting resistance if not used properly, Max von Kleist of the Free University of Berlin said.

The "Purpose 2" study involved nearly 3,300 HIV-negative people who engaged in frequent sexual activity. According to the journal, two individuals in the lenacapavir group (around 2,200 participants) and nine in the group treated for comparison with Truvada (around 1,100 participants) became infected with HIV.

Lenacapavir reduced the infection risk by 96% compared to the background incidence, it said. Both treatments were well-tolerated.

Globally, HIV infections are on the rise, according to a UN report published on Tuesday, with nearly 40 million people living with the virus, the majority in sub-Saharan Africa.