NIH Record - National Institutes of Health

Long-Acting Injectable Form of HIV Prevention Outperforms Daily Pill

Close-up of injection with gloved hands holding syringe at exposed upper arm
A long-acting form of cabotegravir injected was more effective than daily oral Truvada.

A pre-exposure prophylaxis (PrEP) regimen containing an investigational long-acting form of the HIV drug cabotegravir injected once every 8 weeks was more effective than daily oral Truvada at preventing HIV acquisition among cisgender men who have sex with men and transgender women who have sex with men in a clinical trial sponsored by NIH. 

While both methods were highly effective for HIV prevention in the study population, the final data analysis indicated that cabotegravir had a superior protective effect. Findings from the study, called HPTN 083, were to be discussed during the 23rd International AIDS Conference.

The only currently licensed PrEP medications—daily oral pills containing the HIV drugs tenofovir and emtricitabine—are highly effective at preventing HIV when taken as prescribed. However, taking a pill daily can be challenging. A long-acting form of PrEP could offer a less frequent, more discreet option that may be more desirable for some people. HPTN 083 and an ongoing companion study called HPTN 084, which is evaluating long-acting injectable cabotegravir for HIV prevention in cisgender women in sub-Saharan Africa, are sponsored by NIAID. 

In May 2020, a review of HPTN 083 data indicated a high level of efficacy for long-acting injectable cabotegravir among cisgender men and transgender women who have sex with men. The current results are based on a more extensive analysis of interim data from 4,566 study participants.

Overall, the rate of HIV acquisition in the participants was low. Among the 52 participants who acquired HIV, 13 were in the study group who received the cabotegravir-based PrEP regimen plus placebo daily oral tablets, and 39 were in the group who received daily oral Truvada plus placebo injections. Detailed analysis of these data indicated that the superior efficacy of cabotegravir was statistically significant.

Both products were safe and generally well-tolerated. Participants in the cabotegravir group were more likely to experience fever and pain or tenderness at the injection site compared to those in the Truvada group, who received placebo injections. Those in the Truvada group were more likely to report nausea. 

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Associate Editor: Dana Talesnik
Dana.Talesnik@nih.gov (link sends e-mail)

Assistant Editor: Eric Bock
Eric.Bock@nih.gov (link sends e-mail)

Staff Writer: Amber Snyder
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