April 13, 2026 - FDA Reminds More Than 2,200 Sponsors and Researchers to Disclose Trial Results

The U.S. Food and Drug Administration has reminded more than 2,200 medical product companies and researchers of the requirements to submit certain clinical trial results information to ClinicalTrials.gov. Companies and researchers often fail to disclose negative trial results, resulting in significant gaps in the public record and a publication bias that obscures the true landscape of drug development outcomes-overrepresenting successes and underrepresenting failures. This gap can also create a distorted perception of the safety and efficacy of medical products.

According to an internal analysis, 29.6% of studies that are highly likely to fall under mandatory reporting requirements have no results information submitted to ClinicalTrials.gov. Studies subject to the mandatory reporting requirements include interventional studies with a U.S. nexus and an FDA-regulated product that are past the deadline to report; it excludes Phase 1 and device feasibility studies.

"Far too often, companies are suppressing unfavorable clinical trial results and keeping them secret from patients and the scientific community. Those sponsoring clinical trials have an ethical obligation to make results public regardless of the data's influence on the company's share price," said FDA Commissioner Marty Makary, M.D., M.P.H. "Too many clinical trial sponsors and researchers are failing to report their results, leaving important information unavailable to clinicians and other researchers. If you are a doctor deciding whether or not to prescribe a medication to a patient, you deserve to have the best data about clinical studies on that medication."

Certain clinical trial sponsors and researchers are required to submit clinical trial results information to ClinicalTrials.gov one year after trial completion. On March 30, 2026, the agency sent messages to more than 2,200 companies and researchers (associated with more than 3,000 registered clinical trials, including some that were publicly funded) that do not appear to have submitted required results information to ClinicalTrials.gov, or that may have not completed the National Library of Medicine's quality control review process. The messages seek voluntary compliance with requirements.

The FDA also may send Pre-Notices of Noncompliance and Notices of Noncompliance as part of risk-based compliance efforts related to ClinicalTrials.gov. The messages issued on March 30, 2026, represent an extra step the agency is taking to provide the relevant responsible parties with the opportunity to comply with federal law before the agency considers whether to take further regulatory action.

"I fully support this new initiative to increase the prompt publication-as required by law-of results information from interventional studies of the medical products we regulate," said Tracy Beth Hoeg, M.D., Ph.D., Acting Director of the Center for Drug Evaluation and Research. "We hope that the thousands of messages sent to sponsors and investigators reminding them to publicly report their findings will improve patient safety and keep researchers and the public better informed of benefits and risks of new and investigational products."

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