An on-line public database of clinical trial information, primarily for studies regulated by the Food and Drug Administration (FDA). It is maintained by the National Institutes of Health under the Public Health Service Act.

ClinicalTrials.gov was initially established to improve access to information on clinical trials for serious or life-threatening conditions. In 2007, the FDA Amendments Act expanded the database's scope to require that sponsors submit information on most medical device and drug studies (42 U.S.C. § 282(j)). Phase 1 and feasibility studies are generally excluded.

Sponsors must register studies by submitting protocol information, including:

Within a year after study completion, the sponsor must submit basic results from a registered clinical trial, including tables summarizing:

Sponsors must certify compliance with these disclosure requirements in certain submissions to the FDA. Those that fail to register clinical trials or report their results may subject to fines.