If the new long-acting injectable HIV prevention drug Apretude (cabotegravir/rilpivirine) increases overall use of pre-exposure prophylaxis (PrEP) by 25%, it could halve the rate of new diagnoses in men having sex with men. 2030, according to data presented at the Conference on Retroviruses and Opportunistic Infections 2022 (CROI 2022)
These reductions will be critical to the success of the Ending the HIV Epidemic plan. But models suggest the impact would be lower in areas like Georgia, the state with the highest lifetime risk of HIV.
Ruchita Balasubramanian, MD, of the Johns Hopkins School of Public Health, and her colleagues used an HIV epidemiology algorithm developed by Johns Hopkins to run models of how the epidemic would change in 32 communities as the adoption of Apretude was increasing. Communities included the San Francisco Bay Area, Seattle, Atlanta, Washington, DC, Cleveland and Austin, among others. All of these areas are receiving additional funding from the Centers for Disease Control and Prevention (CDC) as part of the Ending the HIV Epidemic plan.
Balasubramanian’s team ran 1,000 simulations for each location, measuring how their HIV epidemic might change, depending on how many more people started taking HIV prevention pills or Apretude. These included people who switched from daily or on-demand oral PrEP to Apretude, as well as those who restarted PrEP using injections or pills.
Even if nothing changes, current trends suggest that PrEP use would increase from 6% in Sacramento to 25% in New York. According to the model, this would result in a 19% drop in new HIV cases. But if the use of oral or injectable PrEP increased by 10% in each jurisdiction, new transmissions would drop by 33%. With a 25% increase in all areas, new cases would decrease by half.
But these numbers mask inequalities by location. For example, even without the addition of long-acting PrEP, it appears that the San Francisco Bay Area would see its transmission rate drop by 35%. But if the use of long-acting, oral PrEP increased by 10%, new HIV transmissions would be cut in half. With a 25% increase in injectable and oral PrEP, the reduction would be 67%.
However, in metro Atlanta, new transmissions would only drop by 10% if nothing else changed. If the use of PrEP, whether long-acting injectables or pills, increased by 10% by 2030, new HIV transmissions would fall by only 23%. It would take a 25% increase in PrEP use to achieve a 40% reduction. That’s a lower level of HIV prevention, even with much higher PrEP use in Atlanta than there would be for just a 10% increase in San Francisco.
And it didn’t seem like the greater effectiveness of Apretude itself would be the driving factor in the drop in HIV cases. Instead, it was simply increased use of any form of PrEP, regardless of how it was delivered.
“The greatest potential impact of [long-acting injectable] PrEP is in expanding total PrEP uptake in conjunction with oral PrEP,” Balasubramanian and colleagues wrote. “Nevertheless, the availability of [long-acting injectable] PrEP alone, without improving the HIV continuum of care, is unlikely to achieve reductions consistent with [Ending the HIV Epidemic] goals.”
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