Study Examines National Trends in Long-Acting Injectable PrEP Use

In the fight against HIV/AIDS, long-acting injectable pre-exposure prophylaxis (PrEP) has proven an exciting breakthrough. Instead of taking a daily pill to prevent HIV, people can receive an injection from a health care provider every two to six months, depending on the medication. Injectable PrEP is discreet, convenient, and highly effective—largely because people don’t have to remember to take a daily pill.

Use of Injectable PrEP Lower Than Expected

Despite the benefits, a new study led by the Rollins School of Public Health found that only 4% of national PrEP prescriptions were for cabotegravir, a type of long-acting injectable PrEP administered every two months. The findings surprised researchers given strong interest in injectable PrEP expressed by patients and researchers.

The retrospective cohort study looked at over 80% of national PrEP prescriptions between 2022 and 2024. Among the more striking findings were:

• People didn’t stick with injectable PrEP at expected rates. 
• After the first year, just 50% of people were still using injectable PrEP. 
• At the end of their second year, only 23% of users were still using injectable PrEP. 

“For prevention medication to have maximum impact, people need to remain on it for substantial periods of time because risk occurs over time,” says the paper’s senior author, Aaron Siegler, PhD. “We thought that bimonthly injectable medication might resolve challenges seen with daily pills for retaining people in care. Instead, we are seeing similar limitations with injectable PrEP with most people not making it to two full years in care.”

Medicaid Users Were More Likely to Use Injectable PrEP

According to Siegler, part of the disconnect may be related to real and perceived insurance barriers.

• Injectable PrEP users were more likely to have higher copays (up to twice as expensive as oral PrEP) 
• Injectable PrEP users were more likely to have Medicaid as their insurance than people on oral PrEP 

“One of the most striking things we found is that almost double the expected proportion of Medicaid coverage was found for the injectable medication versus oral PrEP, which is kind of counterintuitive,” says Siegler. “If lower uptake was a problem of awareness and knowledge, you would think the Medicaid users would have lower knowledge on average than those with private insurance plans.”

Instead he says this may be due to commercial insurance barriers that Medicaid users do not have. Last June, the FDA approved twice-a-year injectable PrEP medication, lenacapavir. Paired with increased uptake and normalcy surrounding other injectable drugs, like GLP-1s, Siegler notes it will be interesting to see how usage trends and insurance barriers change over time. 

“Injectable PrEP provides nearly perfect prevention of HIV. We should facilitate people making health promoting decisions by removing barriers to accessing injectable PrEP,” says Siegler. “Advances in health technology, such as injectable PrEP, can only have an impact if they are accessible