Long-Acting Injection Preferred Over Daily Pills for PrEP

BRISBANE, Australia – When given a choice for pre-exposure prophylaxis (PrEP) to prevent infection with HIV, women preferred injectable cabotegravir (Apretude) every 2 months rather than an oral pill daily, researchers reported here.

About 78% of women enrolled in the landmark HPTN 084 trial said they preferred the injection over taking the pills, said Mina Hosseinipour, MD, MPH, of the University of North Carolina at Chapel Hill and director of the university's Project-Malawi in Africa, at a press conference where the results were released ahead of presentation at the biannual IAS Conference on HIV Science.

The trial had met its primary endpoint in showing injectable cabotegravir superior to daily oral tenofovir/emtricitabine (Truvada) for preventing HIV infection among largely cisgender women, Hosseinipour told MedPage Today. The parallel HPTN 083 trial showed similar results in men who have sex with men and transgender women.

Following the main randomized HPTN 084 study, Hosseinipour and colleagues offered an open-label extension in 2022 where participants were able to make a choice of which product they would like to use.

Just 22% of the women elected to take the daily tenofovir/emtricitabine pill.

"We have reported the rates of seroconversion previously through the beginning of the study through the first year of the unblinded period," Hosseinipour told MedPage Today. "There were six seroconversions among the people on the cabotegravir arm and 56 seroconversions among the subjects on tenofovir/emtricitabine. We are not reporting on any new seroconversions in the current open-label extension at this time."

Based on the trial results, long-acting injectable PrEP is now poised to be rolled out in multiple African countries, Hosseinipour said.

And that makes it an important and timely question to be asking, said Charles Gilks, MBBS, PhD, chair of bloodborne viruses and sexually transmitted infections at the University of Queensland in Brisbane, in commenting on the study.

"The most important factor was simply personal preference," he noted. "It's striking that nearly eight in 10 participants preferred long-acting injectable cabotegravir."

"This confirms that long-acting PrEP could be a game changer in Africa, where uptake of daily oral PrEP has been far too low," Gilks added. "It's also important that this can target young adolescent women who are in a very vulnerable group in southern Africa for whom prevention interventions have not adequately been taken to scale, and they represent a really important population to reach and provide effective prevention interventions."

"We hope that these findings will increase pressure on companies, governments, and other players to make long-acting PrEP accessible quickly to all those who could benefit not only in Africa, but worldwide," Gilks said.

In the study, researchers enrolled 3,028 individuals in Botswana, Eswatini, Kenya, Malawi, South Africa, Uganda, and Zimbabwe. Of the 2,472 participants who agreed to join the open-label extension, 1,931 chose cabotegravir and 536 tenofovir/emtricitabine.

Among the 1,219 participants originally assigned to receive tenofovir/emtricitabine, 67% opted for PrEP with cabotegravir, delivered as an injection every 8 weeks. Of the 1,253 individuals originally assigned to cabotegravir, 11% opted to switch to the oral treatment in the open-label extension.

Hosseinipour said that when participants were asked about their choices, 77% of those who selected cabotegravir said they preferred receiving the every-8-week injections, 11% said they desired a convenient or discrete PrEP method, 8% said they valued cabotegravir effectiveness, and 4% gave other or no reasons.

Of the 536 participants who opted for tenofovir/emtricitabine, 81% said they preferred pills, 5% said they feared injection pain or side effects, 1% desired pregnancy, 1% were seeking efficient clinic visits, and 12% gave no reason.

In further analyzing the decisions of the women, Hosseinipour said that women who selected cabotegravir for PrEP were more likely to be sexually active but to not live with a partner, to have experienced recent physical intimate partner violence, and to have been paid for sex.

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