Insurance Barriers Tied to Missed Long-Acting PrEP Starts

About 4 in 10 people prescribed long-acting injectable (LAI) HIV preexposure prophylaxis (PrEP) at a Missouri clinic never received an injection, most often because of pharmacy benefit gaps or prior authorization denials, according to a poster presented at IDWeek 2026 in Washington, DC.¹ A second poster found that targeted education improved internal medicine residents' knowledge of and comfort with LAI PrEP.²

Four in 10 People Prescribed LAI PrEP Never Received an Injection

Investigators from Washington University in St. Louis conducted a retrospective electronic health record cohort study at a large Ryan White-funded clinic in St. Louis, Missouri, an Ending the HIV Epidemic priority state.¹ Adults with at least 1 LAI PrEP prescription from February 1, 2022, to July 7, 2026, were included. The team treated the first prescription sent to a pharmacy to start a benefits evaluation as a proxy for patient interest.

Of 726 people with at least 1 completed PrEP visit, 268 were prescribed LAI PrEP. Of these, 163 (60.8%) received it, and 105 (39.2%) did not. The poster's detailed analysis focused on 170 people prescribed LAI PrEP through March 2026, and it did not explain the cutoff. The figures below refer to this group. Of the 170, 100 (58.8%) received an injection, and 70 (41.2%) did not. Among recipients, 83% received cabotegravir (Apretude; ViiV Healthcare) and 17% received lenacapavir (Yeztugo; Gilead Sciences).

Pharmacy Benefit Gaps and Prior Authorization Denials Were Top Barriers

Insurance type differed between groups. Medicaid covered 24.3% of those who did not receive LAI PrEP vs 7.0% of recipients, though most people in both groups had private insurance. Among recipients, 94% had a pharmacy-only benefit, compared with 34% of nonrecipients. More than half of nonrecipients (57%) had no benefit or an unknown benefit type, vs 1% of recipients.

Among the 70 people who did not start LAI PrEP, the most common reasons were lack of a pharmacy benefit (54.3%) and prior authorization denial (41.4%). Prior authorization denials affected 6.0% of recipients. Smaller proportions chose oral PrEP despite approval (7.1%), were lost to follow-up (7.1%), could not meet insurer requirements, such as demonstrating failure of oral PrEP (4.3%), or were uninsured or lost insurance (4.3%). Lack of pharmacy benefit and prior authorization denial were not mutually exclusive. Seven people (4.1% of the 170) transferred clinics specifically to receive LAI PrEP under the medical benefit.

Receiving LAI PrEP was associated with greater PrEP engagement at 12 months. The poster defined engagement as an active PrEP prescription in the electronic health record at 12 months or at chart review if follow-up was shorter. Engagement was 96.0% among recipients and 72.9% among nonrecipients (unadjusted odds ratio [OR], 8.94; 95% CI, 2.89-27.69). The investigators identified 1 HIV seroconversion in a person with intermittent oral PrEP adherence who had been denied LAI PrEP coverage in the year before diagnosis.

Among the 100 recipients, median time from prescription to first injection was 12 days (interquartile range [IQR], 6-23). In this group, 17% switched back to oral PrEP, 15.7% (13 of the 83 who received cabotegravir) switched to lenacapavir, and 17% had at least 1 late injection.

The authors concluded that simpler reimbursement models and expanded Medicaid coverage are needed.

“Interest in LAI PrEP exceeds real-world access, which even with insurance availability, is hampered due to complex reimbursement models and insurance-associated challenges,” they wrote. “Policymakers must address this gap to achieve effective LAI PrEP implementation to end the epidemic.”

Targeted Education Improved Resident Knowledge and Comfort

A second poster, from investigators at UC Davis Health and UChicago Medicine, examined whether education could address low comfort with LAI PrEP among internal medicine residents.² The poster noted that residents under-screen patients in the resident primary care clinic for LAI PrEP eligibility, which reduces prescribing. The introduction described residents at UChicago as having reduced comfort prescribing and managing LAI PrEP.

Residents at any training level (n = 118) were surveyed on knowledge of and attitudes toward oral and LAI PrEP. The poster did not report how many residents completed the second survey. The results informed 20-minute and 40-minute lectures and asynchronous didactic materials on LAI PrEP. Residents were surveyed again after completing some or all of the curriculum. Knowledge differences were compared using χ² tests and attitudes using Mann-Whitney U tests.

Before the curriculum, residents had high confidence in and moderate knowledge of oral PrEP but low confidence in and low knowledge of LAI PrEP. After the curriculum, knowledge deficits improved significantly for patient eligibility, oral PrEP monitoring, and LAI PrEP monitoring (P < .01). Attitudes improved most for knowing monitoring practices for both forms of PrEP and for comfort starting LAI PrEP (P < .01). Motivation to screen for or prescribe LAI PrEP did not change significantly (P > .05).

The authors concluded that multimodal curricula can be implemented across residency programs to improve knowledge of LAI PrEP and encourage prescribing in resident clinics. The poster did not report prescribing outcomes or describe a control group.

References

1. Ramakrishnan A, Mukwekwerere ED, Cardoza N, et al. Long-acting injectable PrEP: interest vs. access in an Ending the HIV Epidemic priority state. Presented at: IDWeek 2026; Washington, DC. Poster P-931.

2. Chen MZ, Hazra A. Improving knowledge deficits of and attitudes towards prescribing long-acting injectable HIV PrEP in resident primary care clinic. Presented at: IDWeek 2026; Washington, DC. Poster P-794.