1Day Sooner is a nonprofit organization that advocates on behalf of volunteers willing to participate in high-risk, high-impact medical research.

1Day Sooner was founded in April 2020 to promote the use of human challenge trials as a way to speed up the development of COVID-19 vaccines. The organization has now expanded to work on other types of challenge trials, as well as other projects such as pandemic preparedness and vaccine equity.

In 2020, 1Day Sooner received two grants totaling $1.1 million from Open Philanthropy.^[1][2]