The epidemiological impact and cost-effectiveness of key population-led PrEP delivery to prevent HIV among men who have sex with men in Thailand: A modelling study

BACKGROUND: Although key populations (KPs), such as men-who-have-sex-with-men (MSM) are disproportionately affected by HIV, many prevention and treatment services are not easily accessible for KP members. To address the needs of KPs, Thailand established pre-exposure prophylaxis (PrEP) service delivery together with and led by KP members. This study determines the epidemiological impact and cost-effectiveness of key population-led (KP-led) PrEP. METHODS: We calibrated a compartmental deterministic HIV transmission model to the HIV epidemic among Thai MSM. Besides KP-led PrEP, we included other Thai service delivery models of PrEP (fee-based PrEP, the government PrEP program).Data on consistent PrEP use (5 years daily use, 95% effectiveness for preventing HIV) came from Thai PrEP delivery models. For the period 2015–2032, we ranged the number of PrEP starters (40,000–120,000), effectiveness of PrEP (45%–95%), and proportion of consistent users (10%–50%). The analysis started in 2015 when PrEP was introduced. A cost-effectiveness ratio of <160,000 Baht per quality-adjusted life year (QALY) over 40 years was cost-effective. FINDINGS: Without PrEP, 53,800 (interquartile range 48,700–59,700) new HIV infections are expected in 2015–2032. KP-led PrEP was found to have the strongest epidemiological impact of all delivery models averting 58% of infections compared to without PrEP. The epidemiological impact depends on the number of PrEP starters and proportion of consistent use. Although all PrEP service delivery models are cost-effective, KP-led PrEP is most cost-effective with incremental cost-effectiveness ratios of 28,000–37,300 Thai Baht per QALY. INTERPRETATION: Our model projects KP-led PrEP having the greatest epidemiological impact and being the most cost-effective service delivery model of PrEP in Thailand. FUNDING: This study was supported by the 10.13039/100000200US Agency for International Development and 10.13039/100009054U.S. President’s Emergency Plan for AIDS Relief through the Linkages Across the Continuum of HIV Services for Key Populations cooperative agreement (AID-OAA-A-14- 0045) managed by 10.13039/100011071FHI 360.