Financial incentives to motivate treatment for hepatitis C with direct acting antivirals among Australian adults (The Methodical evaluation and Optimisation of Targeted IncentiVes for Accessing Treatment of Early-stage hepatitis C: MOTIVATE-C): protocol for a dose-response randomised controlled study

Untreated hepatitis C virus (HCV) infection can result in cirrhosis and hepatocellular cancer. Direct-acting antiviral (DAA) therapies are highly effective and have few side effects compared to older interferon-based therapy. Despite the Australian government providing subsidised and unrestricted access to DAA therapy for chronic HCV infection, uptake has not been sufficient to meet the global target of eliminating HCV as a public health threat by 2030. This study will offer people with HCV financial incentives of varying values in order to evaluate its effect on initiation of DAA therapy in primary care. Australian adults (18 years or older) who self-report as having current untreated HCV infection can register to participate via an automated SMS-based system. Following self-screening for eligibility, registrants are offered a financial incentive of randomised value (AUD 0 to 1000) to initiate DAA therapy. Study treatment navigators contact registrants who have consented to be contacted, to complete eligibility assessment, outline the study procedures (including the requirement for participants to consult a primary care provider), obtain consent, and finalise enrolment. Enrolled participants receive their offered incentive on provision of evidence of DAA therapy initiation within 12 weeks of registration (primary endpoint). Balanced randomisation is used across the incentive range until the first analysis, after which response-adaptive randomisation will be used to update the assignment probabilities. For the primary analysis, a Bayesian 4-parameter EMAX model will be used to estimate the dose–response curve and contrast treatment initiation at each incentive value against the control arm (AUD 0). Specified secondary statistical and economic analyses will evaluate the effect of incentives on adherence to DAA therapy, virological response, and cost-effectiveness. This project seeks to gain an understanding of the dose–response relationship between incentive value and DAA treatment initiation, while maximising the number of people treated for HCV within fixed budget and time constraints. In doing so, we hope to offer policy-relevant recommendation(s) for the use of financial incentives as a pragmatic, efficient, and cost-effective approach to achieving elimination of HCV from Australia. ANZCTR (anzctr.org.au), Identifier ACTRN12623000024640, Registered 11 January 2023 ( https://anzctr.org.au/Trial/Registration/TrialReview.aspx?id=384923 isReview=true ).