Browse All Conditions
Explore 28,708 medical conditions with active and completed U.S. clinical trial data drawn from ClinicalTrials.gov. According to ClinicalTrials.gov, the NIH registry maintained by the National Library of Medicine contains more than 500,000 studies in more than 220 countries. The 2007 FDAAA requires registration for most FDA-regulated studies. See our methodology for refresh cadence.
PlainTrial's condition directory indexes every disease, disorder, syndrome, and medical condition with at least one clinical study registered on ClinicalTrials.gov. Each entry links to a per-condition profile page showing recruiting trials, completed studies, phase distribution, sponsor mix, and geographic coverage. We use the MeSH-aligned condition names submitted by trial sponsors to the National Library of Medicine, so a condition you find here is the same condition a clinician would search on PubMed or a researcher would tag in a grant application.
Use the alphabetical index to browse the full list, or sort by trial volume to find conditions with the deepest active research pipelines. Conditions with a "Recruiting" count in the third column have at least one trial currently enrolling participants - click through to see locations and eligibility. Conditions with high trial counts but zero recruiting slots usually reflect a maturing pipeline (Phase 3 studies are enrollment-closed) or a condition where standard-of-care has shifted research focus to combination therapies and post-approval surveillance.
The directory is comprehensive but not equally deep across conditions. Rare diseases may show fewer than a handful of trials because patient populations are limited - this is a feature of clinical research, not an indexing gap on our end. Common conditions (cancer subtypes, diabetes, hypertension, depression) show dozens to hundreds of studies because they attract the broadest sponsor investment. Every number on this page comes directly from ClinicalTrials.gov; we do not manually edit counts, and we update from the NLM bulk-export on a regular cadence so what you see reflects the most recent registry state we have ingested.
† Condition counts include only the 60,823 of 175,638 indexed trials (35%) that have a condition list: 92% of recruiting and active trials but 24% of completed ones, so completed and closed studies are under-counted. How the counts are built
28,708 conditions