Scale-up of Direct-Acting Antiviral Treatment in Prisons Is Both Cost-effective and Key to Hepatitis C Virus Elimination

Abstract 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 statewide prison services incorporating long-term outcomes across custodial and community settings. Methods A dynamic model of incarceration and HCV transmission among people who inject drugs (PWID) in New South Wales, Australia, was extended to include former PWID and those with 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 (2021–2060) discounted at 5% per annum. Univariate and probabilistic sensitivity analyses were performed. Results Scaling up HCV treatment in the statewide 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 of 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. Conclusions Scaling up HCV testing and treatment in prisons is highly cost-effective and should be considered a priority in the national elimination strategy. Clinical Trials Registration NCT02064049.


Costing for HCV testing
The testing pathways for HCV require an antibody test for exposure followed by an RNA test for confirmation of active infection.The testing pathways involve different professional staff by different approach in different settings.Table S1 presents the testing pathways and their activities and various staff (coloured) who could attend for these activities.HCV diagnosis costs were estimated by the weighted average of different testing strategies in the community and prison, based on the testing and treatment occurred in community health centres, drug centres general practice, specialist clinics, and other settings from the REACH study, a national observational cohort that includes 33 diverse study sites from ACT, NSW, NT, QLD, SA, TAS, VIC and WA. 1 The numbers of patients by injecting drug use status were used to estimate the weighted average of current PWID and former PWID.The weighted average costs in former PWID higher than those of current PWID were due to higher proportion of patients cared by specialists who charge higher costs.

Costing of DAA treatment and monitoring
The scale-up of DAA treatment in prisons involves multiple (three) visits by dedicated nurses with presence of prison guards.The tests at each monitoring visit in different time points are presented in Table S2.Based on the SToP-C study protocol, additional three visits were scheduled. 2Labour unit costs were based on Public Health System Nurses' and Midwives' (State) Award for nursing staff and Award of Industrial Relations Commission for correctional officers. 3Pathology costs were sourced from the Australian Medical Benefits Scheme (MBS). 4he pharmaceutical costs of DAA treatment was based on the analysis of Pharmaceutical Benefits Scheme (PBS) claimed data, although a fixed contract (fixed costs irrespective of quantity consumed) for supply of DAA has been agreed between the Australian Government and the manufacture. 5As the fixed contract involved negotiation of risk-sharing agreement with a complex rebate system between the pharmaceutical manufacturers and the Australian government, the true cost was difficult to estimate, but the PBS claimed data offered an indication of the DAA treatment costs for HCV in the context of Australian healthcare system.DAA dispensing cost in prison was estimated by an ingredient-based costing, considering program management & administration, equipment, pharmacy staff, custodial staff, administration overhead (IT, finance, and payroll).DAA dispensing cost in the community was estimated by the cost items of PBS reimbursements to pharmacist including dispensing fee, maximum ex-manufacturer mark-up, Tier three Administration, Handling and Infrastructure (AHI) fee, and concession patient contribution. 6 HIV & HBV serology X Pregnancy Test (serum or urine) X X * Additional visits in the SToP-C study

Costing of chronic hepatitis C management
Costs of chronic hepatitis C related care were updated from the previous study.36Micro-costing methods were used to determine the quantities of healthcare services and annual costs of care for patients with HCV stages F0-F3 (medical management in subsequent years in Table S3), F4 (medical management for compensated cirrhosis in subsequent years in Table S4), decompensated cirrhosis/liver failure (healthcare resources required per annum in Table S5), hepatocellular carcinoma (healthcare resources required per annum in Table S6), liver transplant, and post-transplant care (healthcare resources required per annum in Table S7).Costs included specialist visits, clinical care nurse visits, pathology, medical procedures, and hospital admissions.Unit costs were obtained from the MBS (assuming 100% government benefits) for medical services, procedures, and pathology tests.Medication costs were sourced from the Australian Pharmaceutical Benefits Scheme (PBS). 4,6npatient medical procedures and stays were sourced from the National Hospital Cost Data Collection using Australian Related fined Diagnosis Related Groups (AR-DRG). 7

Table S1 : Schedule of assessments in HCV testing prior to DAA treatment X
-Prison CNS+CNC, X-Prison CNS+ID, X-GP, X-Specialist, X -Testing * Percentage of participants applicable to the test and service

Table S7 : Healthcare resources requirement in post-liver transplant
1 in 20 patients per annum, * 1 in 5 patients required palliative care and social worker, ** 1 in 2 patients need the procedures