Gilead’s experimental biannual HIV prevention shot, lenacapavir, has demonstrated 100% effectiveness in a late-stage trial, the company announced on Thursday.
During an interim analysis of the study, involving approximately 2,000 women, none of those who received lenacapavir contracted HIV. This prompted the independent data monitoring committee to advise Gilead to unblind the Phase 3 trial and extend the treatment to all participants. Those in the control group had been receiving standard daily pills.
This development signifies a significant advancement for Gilead in its quest to expand its HIV prevention portfolio. The news led to a 7% rise in the company’s shares on Thursday.
Gilead’s vice president of clinical development for HIV, Jared Baeten, emphasized the importance of offering diverse PrEP (pre-exposure prophylaxis) options, stating, “What the world needs is persons to have more PrEP choices so they can make the choice of the solution that’s going to work best for them.”
Before seeking approval from the U.S. Food and Drug Administration (FDA), Gilead aims to replicate these promising results in another Phase 3 study involving men who have sex with men, expected to be released later this year or early next year. Positive outcomes from this study could lead to the availability of lenacapavir for PrEP as early as 2025.
Gilead’s Truvada, approved over a decade ago, was the first PrEP medication for individuals at high risk of HIV. While daily pills currently dominate the market, pharmaceutical companies are now focusing on developing longer-acting treatments.
When taken correctly, PrEP can reduce the risk of contracting HIV from sex by 99% and from injected drug use by 74%. However, data from the Centers for Disease Control and Prevention (CDC) reveal that only about a third of those who could benefit from PrEP in the U.S. are currently taking it.
Health advocates are hopeful that longer-acting options will appeal to those unable or unwilling to adhere to a daily pill regimen, potentially curbing the spread of HIV, which caused around 1 million new infections globally in 2022.
Bruce Richman, founding executive director of the nonprofit Prevention Access Campaign, highlighted the necessity of more PrEP options, saying, “It’s really important to have more options than daily pills because the orals aren’t going to get us to the end of the epidemic. We need to make sure that people have options to meet with their habits.”
The FDA approved the first injectable PrEP, Apretude, in 2021, which is administered every other month. According to its manufacturer, ViiV, approximately 11,000 people are currently using Apretude.
Tim Oliver, a 28-year-old public health worker in New York, finds Apretude’s bi-monthly injections manageable but notes that some friends prefer the daily pill. A longer-acting alternative like lenacapavir could appeal to more patients.
RBC Capital Markets analyst Brian Abrahams projects that lenacapavir will significantly boost interest in HIV prevention, estimating peak sales of nearly $2 billion. In comparison, Gilead’s newer PrEP pill, Descovy, generated about $2 billion in revenue last year.
Activists are urging Gilead to ensure lenacapavir’s accessibility in low and middle-income countries, criticizing the high costs of its HIV treatments. Descovy, for instance, has a list price of $26,000 annually.
In its announcement, Gilead indicated plans to address the availability of lenacapavir in resource-limited countries with high HIV incidence rates.