Evolving landscape of economic evaluations of HIV pre-exposure prophylaxis and pre-exposure prophylaxis implementation strategies: a systematic review.

introductionEconomic evaluations of HIV pre-exposure prophylaxis (PrEP) and associated implementation strategies guide evidence-based policies, programmes and resource allocation. Since 2015, there has been an evolution in PrEP modalities, implementation strategies and prioritization of key populations with unmet HIV prevention needs, alongside the scale-up of other HIV prevention interventions. Our systematic review describes the evolving landscape of economic evaluations of PrEP to help identify evidence gaps relevant to the current HIV epidemic and response (PROSPERO: CRD42016038440).

methodsWe searched five databases, without language restrictions, for peer-reviewed economic evaluations from inception to 21 August 2025. We describe the evolution of study characteristics over time, including the perspective of analysis, region, population, PrEP modality/implementation strategy and comparators.

resultsOf 5400 studies identified, 128 met inclusion criteria, of which 94 examined HIV epidemics in 2015 or later and 17 adopted a societal perspective. HIV epidemics studied primarily spanned countries in sub-Saharan Africa (N = 51) and in North America (N = 34). Modelled populations for receipt of PrEP primarily comprised: gay, bisexual and other men who have sex with men (N = 73), female sex workers (N = 26), serodifferent partnerships (N = 17) and persons who inject drugs (N = 12). Most evaluated oral, daily PrEP (N = 76), followed by long-acting injectable PrEP (N = 17), on-demand PrEP (N = 16) and others (e.g. vaginal ring, topical gel; N = 7). Twelve studies compared different PrEP modalities with each other. Five studies evaluated different implementation strategies to increase PrEP uptake, adherence and persistence. Of the 123 studies that compared PrEP to a combination of other HIV prevention interventions, only 31 scaled up at least part of the comparator over time. DISCUSSION: To support decision-making, future economic evaluations should consider costs and benefits beyond the health system (society) and consider comparators that better reflect the current HIV response across regions and populations. The increasing availability of novel PrEP modalities allows future studies to evaluate a mix of PrEP modalities and person-centred implementation strategies.

conclusionsThe growing number of PrEP economic evaluations have not kept pace with emerging PrEP modalities or the current HIV epidemic/response, resulting in challenges in making evidence-based policies, programmes and resource allocation.