Awareness about and willingness to use long-acting injectable pre-exposure prophylaxis (LAI-PrEP) among people who use drugs.

In the Bangkok Tenofovir Study of oral pre-exposure prophylaxis (PrEP; TDF/FTC), adherence was poor. Long-acting injectable pre-exposure prophylaxis (LAI-PrEP) for HIV prevention may help overcome adherence challenges and is currently being tested in clinical trials, but not in people who use drugs (PWUD), an important key population that remains highly vulnerable to HIV. Since PWUD are not currently included in trials of LAI-PrEP, we sought to examine awareness about LAI-PrEP and factors associated with willingness to use LAI-PrEP in this understudied population. Participants included 234 HIV-negative people with opioid use disorder and self-reported HIV-risk behaviors recruited from Connecticut's largest addiction treatment program. We analyzed data from a standardized assessment using audio computer-assisted self-interview (ACASI) to assess the independent factors associated with willingness to use LAI-PrEP. While only 25.6% of participants were aware of LAI-PrEP (67.1% had heard of oral PrEP), after being given a description of it, 73.5% were willing to use it, if it were available. Participants were most commonly concerned about long-term side effects (76.9%) of LAI-PrEP. Independent correlates of willingness to use LAI-PrEP were female sex (aOR = 2.181, p = 0.018), recent visit to healthcare provider (aOR = 2.9, p = 0.023), high perceived risk of acquiring HIV (aOR = 3.3, p = 0.007), and having previously taken oral PrEP (aOR = 3.284, p = 0.017). Findings suggest that PWUD are highly interested in PrEP, especially in LAI-PrEP formulations. Our results indicate the potential for LAI-PrEP, as an alternative to oral daily PrEP, to be implemented into existing evidence-based HIV-based HIV prevention efforts that target high-risk PWUD.