Background
The Surveillance and Treatment of Prisoners with hepatitis C (SToP-C) study demonstrated that scaling-up of direct-acting antiviral (DAA) treatment reduced hepatitis C virus (HCV) transmission. We evaluated the cost-effectiveness of scaling-up HCV treatment in state-wide prison services incorporating long-term outcomes across custodial and community settings.
Methods
A dynamic model of incarceration and HCV transmission amongst people who inject drugs (PWID) in New South Wales, Australia, was extended to include former PWID and long-term HCV progression. Using Australian costing data, we estimated the cost-effectiveness of scaling-up HCV treatment in prisons by 44% (as achieved by the SToP-C study) for 10 years (2021-2030) before reducing to baseline levels, compared to a status-quo scenario. The mean incremental cost-effectiveness ratio (ICER) was estimated by comparing the differences in costs and quality-adjusted life-years (QALYs) between the scale-up and status-quo scenarios over 40 years (2021 to 2060) discounted at 5% per annum. Univariate and probabilistic sensitivity analyses were performed.
Results
Scaling-up HCV treatment in the state-wide prison service is projected to be cost-effective with a mean ICER of A$12,968/QALY gained. The base-case scenario gains 275 QALYs over 40 years at a net incremental cost A$3.6 million. Excluding DAA pharmaceutical costs, the mean ICER is reduced to A$6,054/QALY. At the willingness-to-pay threshold of A$50,000/QALY, 100% of simulations are cost-effective at various discount rates, time horizons, and changes of treatment levels in prison and community.
Conclusion
Scaling-up HCV testing and treatment in prisons is highly cost-effective and should be considered a priority in the national elimination strategy.