NIH launches two clinical trials on long-acting HIV PrEP

On June 4, 2024, the United States National Institutes of Health (NIH), including the National Institute of Allergy and Infectious Diseases (NIAID) and the National Institutes on Drug Abuse, announced the launch of two clinical trials testing on long-acting human immunodeficiency virus (HIV) pre-exposure prophylaxis (PrEP) through the HIV Prevention Trials Network (HPTN).

The studies, sponsored and funded by Gilead Sciences, will focus on a long-acting version of lenacapavir administered every six months.

Lenacapavir, sold under the brand name Sunleca, is an FDA-approved antiretroviral therapy that can be used alongside other drugs to treat HIV in patients with multi-drug resistant HIV; however, several studies are looking at the drug’s potential in preventing HIV.

According to clinicalinfo.hiv.gov, lenacapavir is a capsid inhibitor that interferes with HIV’s external protein shell that protects its genetic material and enzymes. The interference prevents and minimizes viral replication. The NIH notes that it is the first long-acting HIV drug that only has to be administered twice a year.

With evidence of the drug’s potential in preventing HIV, researchers are enrolling cis-gender women in the PURPOSE 3/HPTN-102, focusing on Black women and other women of color. The CDC estimates that cis-gender women account for 18% of new HIV cases in the US; however, they are often underrepresented in HIV research.

“Ending the HIV epidemic means ending it for everyone — including and especially women, who are often underrepresented in HIV research and clinical trials and whose need for new HIV prevention options is critical. This is particularly true for women of color, who bear a disproportionate burden of new HIV infections and who often face structural barriers that can inhibit uptake and adherence to available PrEP methods,” said PURPOSE 3/HPTN-102 protocol chair Shobha Swaminathan, MD, Professor of Medicine and Director of HIV Services at Rutgers New Jersey Medical School, in the Gilead press release. “This collaborative study is an important milestone in HIV prevention research and, if the results are positive, could help provide an additional PrEP option to a number of women across the US that may fit into their lifestyles.”

The other study, PURPOSE 4/HPTN-103, will be enrolling individuals who inject drugs, which comprise roughly 7% of new HIV cases nationwide.

Both studies will be randomized clinical trials that assign patients to a twice-yearly dose of lenacapavir PrEP or the FDA-approved dosing for oral tenofovir disoproxil fumarate and emtricitabine PrEP. Patients enrolled in both studies will be asked to provide lab samples and qualitative feedback on their experience with their assigned treatment.

“HIV prevention is only effective when people are able to access and adhere to the prevention methods that fit within their lives, and a twice-yearly subcutaneous injectable could be an important option for some people for whom existing PrEP modalities — for varying reasons — are not feasible. Gilead is proud to partner with NIH, HPTN, and members of communities across the US on these important studies, recognizing that lenacapavir for PrEP, if deemed safe and effective, could potentially help more people in more populations, prevent HIV,” added Jared Baeten, MD, PhD, Vice President, HIV Clinical Development, Gilead Sciences.