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 preexposure prophylaxis (PrEP). We developed 2 PrEP cascades for Australia's primary HIV-affected population, gay and bisexual men. METHODS: Data were drawn from 2 national, repeated, cross-sectional surveys (the Gay Community Periodic Surveys and PrEPARE Project). One cascade had 3 steps, and the other had 7 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 2 steps using multivariate logistic regression. RESULTS: Thirty-nine thousand six hundred and seventy non-HIV-positive men participated in the Periodic Surveys during 2014-2018. 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