Related Notices
NOT-OD-26-032 The National Institutes of Health has announced that Basic Experimental Studies Involving Humans (BESH) will no longer be considered clinical trials, effective for applications submitted on or after May 25, 2026.
What is Changing
BESH studies, designed to understand fundamental biological or behavioral processes without the intent to directly advance health or change clinical practice. will no longer fall under the NIH Clinical Trial Definition. As a result, BESH studies will not be subject to clinical trial requirements, including registration and results reporting in ClinicalTrials.gov.
What Stays the Same
BESH research must continue to comply with human subjects protections, the NIH Data Management and Sharing Policy, and all other applicable laws and regulations. Currently funded BESH studies should follow their existing Terms and Conditions of Award and applicable flexibility guidance.
Additional notes:
- NIH will issue further guidance and examples to help distinguish BESH from clinical trials and observational studies.
- BESH-specific NOFOs are expected to expire for due dates on or after May 25, 2026, as BESH research will be accepted under Clinical Trials Not Allowed companions.