Welcome to Trials Tracker

Trials Tracker was developed by Rob Wagner and Amy Knopf Associate Professor of Nursing, Indiana University. We created the site to help scientists, academics, journalists, legislators and the public seeking information about clinical trials jeopardized by the National Institutes of Health (NIH) award terminations and funding freezes and delays.

The project reflects a partnership with the founders of Grant Watch—Noam Ross, Executive Director of rOpenSci, and Scott Delaney, Research Scientist at the Harvard T.H. Chan School of Public Health.

Trials Tracker integrates data from Grant Watch and the AACT Database to match affected NIH awards to registered clinical trials using two identification numbers — the NCT ID (an 11 character string of NCT followed by an 8 digit serial number) and the NIH award number (a 14-16 character ID). See the Getting Started tab for more information about how to use this site. The last sync took place 7/9/2025, 5:52:50 PM.

For inquiries, please email Amy Knopf at support@trialstracker.com.

Context

NIH Awards

The NIH is the world's largest public funder of biomedical research, with a FY25 budget of nearly $48 billion, 82% of which supports extramural research. Each year, the NIH gives approximately 60,000 grants, or awards, to researchers and their affiliated institutions after a lengthy, rigorous and highly competitive review process. Awards support all aspects of the biomedical research enterprise — from basic science, to clinical trials, to behavioral and translational research studies — in addition to sustaining research infrastructure and training the next generation of scientists. The breadth of work NIH supports makes it difficult to describe the short- and long-term impacts of award terminations. In this first iteration of Trials Tracker we focus specifically on the relationship between NIH awards and registered clinical trials.

The National Clinical Trials Registry

ClinicalTrials.gov is a registry of trials that are funded by the U.S. government, private foundations, the pharmaceutical industry, and other institutions. We focus specifically on trials funded by NIH. The NIH requires researchers to register their studies in ClinicalTrials.gov when:

• the study involves human participants
• participants are prospectively assigned to an intervention
• the study is designed to evaluate the effect of the intervention on the participants
• the effect being evaluated is a health-related biomedical or behavioral outcome

You can find further information regarding NIH requirements for trial registration, including a definition of terms, here.

All registered clinical trials are assigned a unique identifier called the NCT ID. The format is an 11 character string of NCT followed by an 8 digit serial number. Similarly, each NIH award is assigned a 14-16 character ID. The structure of NIH award numbers is explained in detail here. Trials Tracker links awards to studies through matches between these two identification numbers.