HIV preexposure prophylaxis cascades to assess implementation in Australia: Results from repeated, national behavioral surveillance of gay and bisexual men, 2014-2018

Background: HIV prevention cascades can assist in monitoring the implementation of prevention methods like pre-exposure prophylaxis (PrEP). We developed two PrEP cascades for Australia’s primary HIV-affected population, gay and bisexual men.
Methods: Data were drawn from two national, repeated, cross-sectional surveys (the Gay Community Periodic Surveys and PrEPARE Project). One cascade had three steps, the other seven steps. Trends over time were assessed using logistic regression. For the most recent year, we identified the biggest drop between steps in each cascade and compared the characteristics of men between the two steps using multivariate logistic regression.
Results: Thirty-nine thousand six hundred and seventy non-HIV-positive men participated in the Periodic Surveys during 2014-18. PrEP eligibility increased from 28.1% (1901/6762) in 2014 to 37.3% (2935/7878) in 2018 (p<0.001), awareness increased from 29.6% (563/1901) to 87.1% (2555/2935; p<0.001), and PrEP use increased from 3.7% (21/563) to 45.2% (1155/2555; p<0.001). Of 1,038 non-HIV-positive men in the PrEPARE Project in 2017, 54.2% (n=563) were eligible for PrEP, 97.2% (547/563) were aware, 67.6% (370/547) were willing to use PrEP, 73.5% (272/370) had discussed PrEP with a doctor, 78.3% (213/272) were using PrEP, 97.2% (207/213) had recently tested, and 75.8% (157/207) reported reduced HIV concern and increased pleasure due to PrEP. The break point analyses indicated that PrEP coverage was affected by geographical availability, education level, employment, and willingness to use PrEP.
Conclusion: PrEP eligibility, awareness and use have rapidly increased among Australian gay and bisexual men. The cascades identify disparities in uptake by eligible men due to socioeconomic factors and PrEP’s acceptability.