Changes in evidence used for FDA Novel Drug Approvals: 2016-2024

BACKGROUND: The 21st Century Cures Act (2017) was enacted during a period of evolving FDA flexibility in evidentiary standards for drug approval. To examine trends before and after implementation, we independently reviewed all novel drugs approved between 2016 and 2024. METHODS: We constructed a database of all novel FDA approvals from January 1, 2016, through December 31, 2024. Each study linked to an approved drug (N = 6,763) was cataloged by study number, sponsorship, and timing of results reporting relative to completion. RESULTS: Since 2016, the number of studies supporting approval has steadily declined. Beginning in 2017, the modal number of studies per approval fell to one. Industry sponsorship increased while NIH-supported studies decreased. Average time to public posting of results exceeded the one-year statutory limit. CONCLUSIONS: In the post-2016 period, FDA approvals were supported by fewer studies and by a greater proportion of industry-sponsored studies. Although this may accelerate access to new therapies, it raises concerns about the strength of evidence for safety and effectiveness.