Gilead’s biannual HIV shot reduced risk of infections by 96 percent, company says

Drugmaker Gilead Science announced Thursday that its biannual injections to prevent against HIV had slashed the risk of infection from the virus by a staggering 96 percent.

The California biopharmaceutical company said that its drug lenacapavir had “demonstrated superiority” over Truvada, a tablet taken daily to fight HIV infection, and has been the primary option for pre-exposure prophylaxis, or PrEp.

“With such remarkable outcomes across two Phase 3 studies, lenacapavir has demonstrated the potential to transform the prevention of HIV and help to end the epidemic,” Chief Executive Officer Daniel O’Day said in a statement.

A recent Phase 3 clinical trial found that 99.9 percent of participants who took lenacapavir for prevention were not infected. Gilead said there were two incident cases among a group of 2,180 participants in the trial. Comparatively, there were nine cases out of 1,087 individuals in the Truvada group. Gilead said lenacapavir was 89 percent more effective than Truvada.

The trial included cisgender men, transgender men, transgender women, and gender non-binary individuals who have sex with partners assigned male at birth. Participants were from countries around the world, including Argentina, Brazil, Mexico, Peru, South Africa, Thailand, and the United States.

The double-blind trial was unblinded early because it met its key efficacy endpoints, Gilead said, allowing lenacapavir to be offered to all participants.

Both lenacapvir and Truvada were generally well-tolerated and Gilead said there were no significant or new safety concerns.

The news comes after a June trial of lenacapavir was found to be 100 percent effective in preventing new HIV infections in women. There were no infections in women and girls from South Africa and Uganda who got the shot.

O’Day said that his company would work with its regulatory, community, and government partners to ensure that, “if approved, we can deliver twice-yearly lenacapavir for PrEP worldwide, for all those who want or need PrEP.”

The data from both trials will be used to start the drug approval process around the world by the end of the year. Gilead said that this could support an initial launch of lenacapavir by next year.

While the use of the shots has not been approved globally by itself, lenacapavir has been authorized by the Food and Drug Administration for the treatment of HIV in adults, in combination with other medicines.

There are still tens of thousands of HIV diagnoses in the U.S. every year, according to the Centers for Disease Control and Prevention, and nearly 5,000 deaths. Nearly half of new HIV infections are in the South.