In 2021, federal regulators approved the first long-acting antiretroviral (LA-ART) injectable, which is a combination of long-acting cabotegravir and rilpivirine. But they only approved it for HIV patients who already had their infections under control with pills. Researchers at University of San Francisco wanted to see if it would work for patients who could not control their infections with pills, whether that was because they had trouble swallowing or remembering, or because they did not have a place to live and faced other life challenges, such as substance use disorder. So, they gave these patients monthly or bimonthly injections and compared their viral loads to other patients who already had their viral loads controlled with oral medication before starting injectable HIV therapy. More than 98% of participants in both groups had what’s known as “viral suppression,” or undetectable levels of HIV, after 48 weeks. It is the largest and longest such comparison.
The research, which was supported by the National Institutes of Health’s National Institute of Allergy and Infectious Diseases, could help stop the spread of HIV, since those who are virally suppressed cannot transmit the virus. The publication of this paper on the journal JAMA was timed to coincide with the presentation of the findings at the 2025 Conference on Retroviruses and Opportunistic Infections (CROI), which is being held in San Francisco from March 9 to 12. The annual conference brings together researchers from around the world who are focused on HIV/AIDS and related conditions. To conduct this evaluation, the researchers relied on patient data from the Special Program on Long-Acting Antiretrovirals to Stop HIV (SPLASH) at Ward 86, the UCSF HIV/AIDS clinic at Zuckerberg San Francisco General Hospital.
They studied data from 370 patients – 129 of whom had detectable viral load levels when they started on injectables, and 241 of whom did not – from January of 2021 through September of 2024. After about 11 months, 99% of those who were virally suppressed when they started the injectable medication continued to have no detectable HIV in their blood. The results were essentially the same for the group that started injectables before getting the virus under control: 98% achieved viral suppression in that period. This is a game changer for patients who have trouble maintaining a regimen that requires multiple pills each day. In a low-barrier long-acting PrEP program in a safety-net setting, permitting same-day or next-day initiation, 85% of injections were on-time, and six-month retention was 83%, surpassing outcomes from most previously-reported oral PrEP studies.
- Edited by Dr. Gianfrancesco Cormaci, PhD, specialist in Clinical Biochemistry.
Scientific references
Bikinesi L et al. Int J Infect Dis. 2025 Feb; 151:107328.
Spinelli MA et al. JAMA. 2024 Nov; 332(18):1574-1575.
Spinelli MA et al. Clin Infect Dis. 2024 Nov 1:ciae531.
Landovitz RJ et al. Lancet HIV. 2023; 10(12):e767-e778.
