Twice-Yearly Injection Offers 100% Protection Against HIV: Study

A twice-yearly injection has shown 100% efficacy in preventing HIV infections in women, according to a study published in the New England Journal of Medicine. The study, funded by U.S. drugmaker Gilead, involved about 5,000 young women and girls in South Africa and Uganda. None of the participants who received the injections, known as lenacapavir, contracted HIV during the study. In contrast, approximately 2% of those given daily prevention pills ended up contracting HIV from infected sex partners.

Salim Abdool Karim , director of an AIDS research center in Durban, South Africa, who was not part of the research, described the level of protection as "stunning."

Lenacapavir, sold as Sunlenca, is currently approved in the US, Canada, Europe, and elsewhere as a treatment for HIV. Gilead is awaiting the results of testing in men before seeking permission to use it to protect against infection.

The study was stopped early due to the unexpectedly positive results, and all participants were offered the shots. The twice-yearly injections could provide a more convenient alternative to daily pills or regular injections, which have seen inconsistent use in Africa.

However, concerns have been raised about the affordability of Sunlenca . As an HIV treatment, the drug costs more than $40,000 a year in the US. Gilead has stated it is too early to determine the cost of Sunlenca for prevention in poorer countries.

Winnie Byanyima, executive director of the Geneva-based U.N. AIDS agency, urged Gilead to share Sunlenca's patent with a U.N.-backed program that allows generic drugmakers to produce cheaper versions of drugs for poorer countries worldwide.

The results of this study represent a significant step forward in the fight against HIV, with further trials ongoing to assess the efficacy of lenacapavir in men, transgender women, and gender nonbinary people.