Epidemiological and economic effect of preference-driven HIV pre-exposure prophylaxis implementation for men who have sex with men and transgender women across 16 countries and territories in the Asia–Pacific region: a modelling study

Background Pre-exposure prophylaxis (PrEP) coverage remains low among men who have sex with men (MSM) and transgender women in the Asia–Pacific region, and discrete choice experiments identified user preferences for PrEP modalities. We aimed to evaluate the epidemiological and economic effects of implementing preference-driven PrEP among MSM and transgender women. Methods We used preference data from large-scale discrete choice experiments in 16 Asia–Pacific countries and territories during May and November, 2022, involving MSM at substantial risk (MSMSR), MSM at low risk (MSMLR), and transgender women for daily oral, on-demand, and long-acting injectable modalities of PrEP. We developed a mathematical model to translate stated preferences into willingness to use PrEP and subsequent coverage levels. We then estimated the annual HIV acquisitions averted and the cost per acquisition averted for three single-modality and one mixed-modality PrEP strategies compared to baseline coverage. Results are reported as medians with 95% uncertainty intervals (UIs). Findings Estimated willingness to use PrEP ranged from 46·8% (range 40·2–81·6) for on-demand PrEP (in MSMLR in Nepal) to 95·2% (95% UI 84·4–97·2) for the mixed-modality PrEP (in transgender women in Laos), with PrEP coverage of 10·8% to 30·8%. Long-acting injectable PrEP yielded the highest reductions in annual HIV acquisitions, from 17·1% (lowering the median number of acquisitions from 112 to 93) for transgender women in Cambodia to 31·8% (median reduction 457 to 310) among MSMSR in Australia. Median cost per acquisition averted was lowest for on-demand PrEP, from US$2302 (95% UI 1610–3370) among transgender women in Viet Nam to $742 727 (430 928–1 357 458) among MSMLR in Japan, and highest for long-acting injectable PrEP, from $21 132 (12 682–34 348) among transgender women in India to $10 315 297 (5 919 094–19 317 799) among MSMLR in Japan. Once HIV incidence is above the critical turning point (0·22–3·22 per 100 person-years), cost per acquisition averted drops sharply from a range of $9890–48 305 000 to $200–200 070. Interpretation Implementation of preference-driven PrEP strategies could substantially reduce HIV incidence. Long-acting injectable PrEP offered the greatest efficacy at the highest cost, whereas on-demand PrEP was the most economically efficient modality. Targeting PrEP to areas with higher incidence can greatly decrease the cost. Funding National Key R&D Program of China; National Natural Science Foundation of China; the Young Elite Professional of the Shaanxi Three Qin Talents Special Support Program; Australian National Health and Medical Research Council Emerging Leadership Grant. Translation For the Chinese translation of the abstract see Supplementary Materials section.