A twice-yearly injection proves effective against HIV

Just two injections a year of a new HIV drug protects young women in Africa from contracting the sexually transmitted disease, results of a new trial show.

In announcing the results, Gilead Sciences Inc. said that its HIV drug, lenacapavir, had proven 100% effective as a preventive treatment.

The company noted that this is the first round of data obtained from its PURPOSE program, which is a set of five HIV prevention trials being conducted around the world.

“With zero infections and 100% efficacy, biannual lenacapavir has proven its potential as an important new tool to help prevent HIV infection,” Dr. Mordad Parsi, Gilead's chief medical officer, said in a press release announcing the results. “We look forward to additional results from the ongoing PURPOSE clinical program and continuing to achieve our goal of helping to end the HIV epidemic for everyone, everywhere.”

The lenacapavir trial, conducted in Uganda and South Africa, tested whether two injections of the drug annually would provide better protection against HIV infection compared to two other daily pills widely used in high-income countries.

Gilead said the results with lenacapavir were very convincing, and the trial was stopped early after an independent data review committee said the injection should be offered to all participants because it clearly provided superior protection against the virus.

None of the 2,134 women who received lenacapavir became infected with HIV, while 16 of the 1,068 women who took Truvada, a daily pill that had been available for more than a decade, became infected with HIV, and 39 of the 2,136 women who got the daily pill became infected. The latest is called "Discovy".

However, Gilead's data has not yet been published in a peer-reviewed journal. The company said it has conducted a second trial of the injection in six other countries, and its results will be reviewed later this year.