Modelling the cost-effectiveness of TasP and PrEP in female sex workers in Cotonou, Benin.

IntroductionTreatment as prevention (TasP) and pre-exposure prophylaxis (PrEP) could impact the HIV epidemic among Female Sex Workers (FSW) but their cost-effectiveness is uncertain in this group. This study aims to model the cost-effectiveness of TasP and PrEP among FSW in Cotonou, Benin. MethodsA demonstration study assessed TasP and PrEP use among FSW in Cotonou. A dynamic HIV transmission model was developed to estimate the impact of this intervention and published elsewhere. Incremental economic costs of the study were collected prospectively capturing both provider and FSW costs. The incremental cost-effectiveness ratio per HIV infection and disability-adjusted life years (DALY) averted were estimated over a 20 year time horizon with costs converted to USD 2020 and both costs and DALYs discounted at 4.5% per year. Different cost scenarios were modelled to investigate the cost-effectiveness of the intervention as delivered by the government reflecting current day implementation and resource costs. ResultsThe mean provider annual economic cost per FSW on TasP was $646, with an initiation cost of $347 and mean annual user costs were $16. The mean initiation costs for PrEP were $268, mean annual provider costs were $359-$499 and annual user cost $15-$21 depending on adherence level. TasP was found to be cost saving for all cost scenarios examined compared to routine HIV care for FSW. PrEP was not cost-effective for any cost scenario, population coverage or adherence level examined. ConclusionOur results support TasP but not PrEP for FSW in our setting. A streamlined, outreach delivery model with reduced costs should be investigated to assess its cost-effectiveness in this setting.