Abstract

Can we permissibly accelerate vaccine testing even if this increases risk to study participants? During the COVID-19 pandemic, researchers, policymakers, and bioethicists debated ways in which vaccine development could be expedited. One suggestion were human challenge trials which only started after safe and efficacious vaccine had already been developed. Was this hesitation justified? Can challenge trials play a role in future pandemics? I defend both a version of challenge trials – a low-dosage challenge trial – and a faster option for post-challenge trial safety testing. My argument draws on a new framework for risks in biomedical research. The new framework, embedded in a broader approach to the ethics of risk, can justify seemingly risky research while remaining strongly protective of the rights and interests of research participants. My argument furthermore draws on considerations about the connection between the risks to study participants, the benefits to nonparticipants, and the number of participants involved.