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The Case for Human Challenge Trials in COVID-19

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Abstract

The COVID-19 pandemic has necessitated rapid research to aid in the understanding of the disease and the development of novel therapeutics. One option is to conduct controlled human infection trials (CHITs). In this article I examine the history of deliberate human infection and CHITs and their utilization prior to the COVID-19 pandemic, key ethical considerations of CHITs in the COVID-19 setting, an analysis of the World Health Organization’s (WHO) Key criteria for the ethical acceptability of COVID-19 human challenge studies, and a review of the two COVID-19 CHITs that have already commenced, their compliance with the WHO criteria and other ethical considerations.

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Notes

  1. The consent form that participants signed stated:

    “The undersigned understands perfectly well that in the case of the development of yellow fever in him, that he endangers his life to a certain extent but it being entirely impossible for him to avoid the infection during his stay in the island, he prefers to take the chance of contracting it intentionally in the belief that he will receive from the said Commission the greatest care and the most skillful medical service.”

    The consent makes no mention of the very high mortality rate of contracting yellow fever at the time of the study. There was also a widely-held belief that Yellow Fever was unlikely to be spread by the mosquito vector route, likely leading to an underestimation of risk by study participants.

  2. For example, the experimentation on prisoners, people with disabilities and other groups by Nazi and Japanese Imperial Army researchers during World War 2. See Weindling et al., 2011

  3. See above section on History of Challenge Trials

  4. Available at: <https://jme.bmj.com/content/46/12>

  5. See above, Section “Payment in CHITs”

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  1. Melbourne Law School, University of Melbourne, Parkville, VIC, Australia

    George P. Drewett

  2. The Northern Hospital, Epping, VIC, Australia

    George P. Drewett

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Drewett, G.P. The Case for Human Challenge Trials in COVID-19. Bioethical Inquiry 21, 151–165 (2024). https://doi.org/10.1007/s11673-023-10309-9

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