On Wednesday local time, the American biopharmaceutical company Gilead Sciences released more research data on the HIV prevention drug "Lenacapavir" in the New England Journal of Medicine. Against the backdrop of the plunge in U.S. stocks, Gilead Sciences' share price rose more than 3%. Researchers pointed out that in experiments conducted on about 5,000 women in South Africa and Uganda, Lenacapavir, injected twice a year, showed 100% effectiveness in preventing HIV infection in women. About 2% of those in the control group who took preventive drugs eventually contracted HIV from an (infected) sexual partner.

In fact, this research trial called "PURPOSE1" was published by Gilead Sciences as early as last month, and was recently published in the "New England Journal of Medicine", supplementing the efficacy and safety results, and was discussed at the 25th World AIDS Conference in Munich, Germany.

Gilead Sciences mentioned in a press release that it expects to have results from "PURPOSE2" later this year. The trial is evaluating the effect of two injections of Lenacapavir a year in men, transgender women and other groups in Argentina, Brazil, Mexico, Peru, South Africa, Thailand and the United States.

Winnie Byanyima, executive director of UNAIDS, said Gilead Sciences has a tool that can change the trajectory of the HIV epidemic.

Byanyima added that her organization is urging Gilead to share Lenacapavir's patents with a U.N.-backed project to allow generic drugmakers to produce cheaper anti-HIV drugs for poor countries around the world.

Professor Linda-Gail Bekker from the University of Cape Town claimed that the prospect of two injections a year was "pretty revolutionary news" for patients. "It gives participants a choice and removes all the stigma surrounding taking medication to prevent HIV."

Experts working to stop the spread of HIV are excited about Lenacapavir, but they worry that Gilead's price tag may make it unaffordable for those who need it most.

In a statement last month, Gilead said it was too early to talk about the cost of Lenacapavir's prevention in poor countries. Dr. Jared Baeten, Gilead's senior vice president of clinical development, said the company is already in talks with generic drugmakers and understands "how important it is to move quickly."

In a separate study presented at the AIDS conference, Andrew Hill of the University of Liverpool and colleagues estimated that once production of lenacapavir is scaled up to treat 10 million people, the price per treatment should drop to about $40.

Dr. Helen Bygrave of Doctors Without Borders said in a statement that if the vaccine was made available in countries with the highest infection rates, it could turn the tide on the HIV epidemic. He hopes Gilead will announce a fair and affordable price so that all countries can purchase the drug.