A medicine already in use to treat HIV also provides complete defense against infection with the virus, according to dramatic new findings presented in the New England Journal of Medicine.
The study, which involved more than 5,000 women between ages 16 and 26 in Africa, demonstrated that twice-yearly injections of lenacapavir (Sunlenca) were 100 percent effective in blocking HIV (human immunodeficiency virus), the virus that causes AIDS (acquired immunodeficiency syndrome). The injections were also well-tolerated and produced no major side effects.
“No adolescent girls or young women receiving twice-yearly lenacapavir acquired HIV infection in this trial,” wrote the study collaborators, led by the author Linda-Gail Bekker, MBChB, the deputy director of the Desmond Tutu HIV Centre at the Institute of Infectious Disease and Molecular Medicine at the University of Cape Town in South Africa.
Lenacapavir, they noted, could be easier for people to use as directed than existing forms of preventive HIV medicine collectively known as PrEP (pre-exposure prophylaxis medicine) that involve more frequent injections or daily pills.
“A twice-yearly PrEP choice could overcome challenges with respect to adherence and result in substantial protection against HIV infection for women worldwide,” the study authors wrote.
Trials of lenacapavir as a preventive medicine are still ongoing in men who have sex with men and transgender individuals. The drug’s maker, Gilead, expects to have those findings in late 2024 or early 2025, at which time the company plans to seek approval by the U.S. Food and Drug Administration (FDA).
“We expect the results [from these trials] to be similar with these other at-risk groups in the United States,” says Philip Grant, MD, a clinical associate professor of medicine at Stanford University in California, whose research focuses on HIV complications. Dr. Grant wasn’t involved in the new lenacapavir research.
Great Strides Against a Persistent Health Problem
Cisgender women account for about half the 1.3 million new HIV infections that occur worldwide each year.
In the United States, men who are gay or bisexual and men who have sex with other men are the population most affected by HIV. But women and men with multiple sex partners and those who use injectable drugs are at significant risk as well.
People in these high-risk groups can prevent HIV infection with Truvada (emtricitabine and tenofovir disoproxil fumarate), a PrEP medication approved by the FDA in 2012 as a daily pill.
Since that time, the FDA approved a second oral preventive treatment, Descovy (emtricitabine and tenofovir alafenamide), and Apretude (cabotegravir), an injectable PrEP medication involving shots every two months.
Existing Preventive Treatments Can Be Challenging to Stick With
Currently approved PrEP options are considered to be 99 percent effective if people take them as directed, according to the Centers for Disease Control and Prevention (CDC).
But there can be issues with taking these drugs consistently, which may give lenacapavir an advantage. In the recent trial, of the 2,134 women given lenacapavir, none contracted HIV. On the other hand, 16 cases were detected in a group of 1,068 women taking Truvada, and 39 infections were recorded among 2,136 women receiving Descovy.
Adherence is often a problem with drugs that block HIV infection. “There are lots of prevention tools out there, and if someone is at risk, it’s important to access one of them, whether it be oral or an injectable, but a lot of people have a hard time taking pills,” says Grant. “People aren’t necessarily great at taking their pills every day.”
When it comes to injectable options, Grant notes that some people may prefer lenacapavir over cabotegravir because it requires just two shots a year compared with six.
How Much Does Sunlenca Cost?
Gilead currently charges more than $40,000 for a year of lenacapavir treatment, although insurance and other financial programs can help lower the cost.
“Once it’s approved for HIV prevention, the price will be looked at again in the United States,” says Grant. “The price will need to go down for it to be more widely used for prevention.”
