High interest for long-acting injectable PrEP among men who have sex with men at most risk for HIV in San Francisco, 2021.

Background Men who have sex with men (MSM) represent a disproportionate total of incident HIV cases. Oral pre-exposure prophylaxis (PrEP) has contributed to significant declines in total HIV incidence. Barriers to PrEP include individual and structural factors that can prevent PrEP adherence and persistence. Long-acting injectable PrEP (LA-IP) can be leveraged to address high incident rates of HIV. Methods This study was a secondary analysis of the National HIV Behavioral Surveillance (NHBS) survey. We measured interest in LA-IP and associated factors among MSM in San Francisco from June 2021 to December 2021. Results Of the 505 MSM who were recruited, 409 reported not living with HIV. Interest in LA-IP among MSM in San Francisco was high (78.0%). Interest was associated with the use of on-demand PrEP (adjusted prevalence ratio [aPR] 3.68, 95% confidence interval [CI] 1.24-10.9), having two or more sexual partners (aPR 3.65, 95% CI 1.89-7.03), and having condomless insertive anal intercourse (aPR 2.15, 95% CI 1.19-3.87). LA-IP was inversely associated with having a high school education or lower (aPR 0.23, 95% CI 0.08-0.70) and being aged 50 years or more (aPR 0.32, 95% CI 0.19-0.56). Strikingly, we found that five of the six participants who were found to have incident HIV infections in this study were interested in LA-IP. Further, they had used oral PrEP in the past 30days with suboptimal adherence. Conclusions These findings suggest that a population with elevated risk for HIV and barriers to daily oral PrEP adherence may find LA-IP a preferable alternative to daily oral PrEP in meeting their HIV prevention needs.