Planning an NIH Application involving Basic Experimental Studies with Humans (BESH)?

On January 29, NIH announced that Basic Experimental Studies with Humans (BESH) will no longer be considered clinical trials by the NIH. See NOT-OD-26-032.

What’s changing?

• Beginning with applications submitted for due dates on or after May 25, 2026, BESH will no longer be considered as clinical trials by NIH.
• As a result, BESH studies will not be required to follow NIH clinical trial requirements, including registration and results reporting in ClinicalTrials.gov.
• BESH must continue to follow all other applicable laws and regulations applicable to human subjects protections and the NIH Data Management and Sharing Policy. 

NIH anticipates expiring all BESH-specific NOFOs with due dates on or after May 25, 2026. After that time, BESH research can be accepted through the Clinical Trials Not Allowed companions of these NOFOs.

NIH will issue a forthcoming Guide Notice with detailed guidance on any necessary instruction or system updates to reflect this revised classification.

Resources

• Clinical Trials/BESH/Observational Webpage

Editor's Note: After publication, we added the third bullet above for clarity.