Ethical Payment to Participants in Human Infection Challenge Studies, with a Focus on SARS-CoV-2: Report and Recommendations

Abstract

To prepare for potential human infection challenge studies (HICS) involving SARS-CoV-2, this report offers an expert analysis of ethical approaches to paying research participants in these studies, as well as HICS more broadly. The report first provides an overarching ethical framework for research payment that divides payment into reimbursement, compensation, and incentive, focusing on fairness and promoting adequate recruitment and retention as counterweights to ethical concerns about undue inducement. It then describes variables relevant to applying this framework to any type of study, including the prospect of direct medical benefit, early participant withdrawal, study setting and location, pandemic circumstances, study budget, and participant perspectives. We conclude that there is no need for a unique payment framework specific to HICS or SARS-CoV-2 HICS, but that there may be features of particular relevance to ethical payment for these studies. Participants have varied motivations for enrolling in HICS, including financial considerations, altruism, and other interests, but undue inducement does not seem to be a significant problem based on available evidence. Payment in these studies should reflect the nature of participant confinement, anticipated discomfort from induced infection, risks and uncertainty, participant motivations, and the need to recruit from certain populations, as relevant. Where HICS involve significant risks and highly contingent social value, special review confirming the ethical permissibility of these studies can help promote confidence in the ethical permissibility of offers of payment to participate in them. We do not propose specific payment amounts for potential SARS-CoV-2 HICS, as these will be highly variable based on the relevant factors described in the report. Instead, we note that it is reasonable to start from payments offered in other similar studies, while adopting a systematic approach based on the ethical framework herein, as reflected in a pragmatic payment worksheet describing goals, coverage, factors to consider, and potential benchmarks.

Keywords: human infection challenge study, challenge trial, SARS-CoV-2, COVID-19, coronavirus, research, payment