Total US Trials
175,638 indexed
Medical Disclaimer: PlainTrial provides public information only. Always consult your healthcare provider before enrolling in a clinical trial.
24,857 trials recruiting now · ClinicalTrials.gov
175,638 US clinical trials, in plain language.
The official US trial registry, made searchable, readable, and free.
175,638 US clinical trials indexed, 24,857 (14%) actively recruiting.
According to ClinicalTrials.gov, the official NIH US trial registry, PlainTrial indexes 175,638 registered studies across 28,708 conditions and 15,742 sponsors. 24,857 trials, about 14%, are currently open to new participants. Use condition, sponsor, or state pages to find recruiting studies with phase mix and enrollment context in plain language.
Search recruiting clinical trials by condition, sponsor, or US state, explore drug-development phase pipelines and rankings, and read plain-language patient guides, every trial record sourced from ClinicalTrials.gov.
Every trial record above is sourced from ClinicalTrials.gov, the NIH's official US trial registry.
175,638
Total Trials
24,857
Recruiting Now
28,708
Conditions
15,742
Sponsors
52
US States & Territories
The national picture
Of 175,638 clinical trials registered across the United States, 24,857 - roughly 14%, or 1 in 7 - are actively recruiting participants right now.
- 24,857
- recruiting now (14% of all registered)
- 28,708
- distinct conditions under study
- 15,742
- sponsors running trials
- 15,530
- in Phase 3, pivotal efficacy trials
Figures reflect the latest ClinicalTrials.gov snapshot mirrored by PlainTrial. A trial's status and phase are reported by its sponsor to the NIH registry.
Trial Phase Pipeline
Drug-development phases follow a regulatory funnel: early safety testing (Phase 1) through pivotal efficacy trials (Phase 3) to post-marketing surveillance (Phase 4).
Drug Development Phase Distribution
Currently Recruiting
24,857 trials
Moderate recruitment
Phase 2 Pipeline
31,395 trials
Phase 2-heavy pipeline
Conditions Tracked
28,708
Phase 2 share of phase-assigned trials 35.3%
31,395 of 89,061 phase-assigned trials
Recruiting share of all trials 14.2%
24,857 of 175,638 total
Currently Recruiting
All recruiting trials → Recruiting
IRIS Registry: Intelligent Research in Sight Registry
American Academy of Ophthalmology
Target: 20,000,000 participants
NCT02485847
Recruiting
A Study Of Deep Learning For Echo Analysis, Tracking, And Evaluation
Mayo Clinic
Target: 10,040,000 participants
NCT07308704
Recruiting NA
The Effects of Medicaid Policy Interventions on Racial Equity in Severe Maternal Morbidity
University of Pittsburgh
Target: 10,000,000 participants
NCT05678699
Recruiting
National Mammography Database
American College of Radiology
Target: 8,000,000 participants
NCT01900821
Recruiting
The Pediatric Anesthesia Quality Improvement Project
The Society for Pediatric Anesthesia
Target: 5,000,000 participants
NCT00674388
Recruiting
Get With the Guidelines-Stroke Registry
American Heart Association
Target: 3,892,063 participants
NCT02693223
Recruiting
Delivery Room Intervention and Evaluation Network
American Academy of Pediatrics
Target: 3,000,000 participants
NCT06803498
Recruiting
Helix Research Network
Helix
Target: 2,000,000 participants
NCT06057181
Recruiting
Observational Pharmaco-Epidemiology Research & Analysis
Epividian
Target: 2,000,000 participants
NCT03813862
Recruiting
Oura Blood Pressure Profile Study
Ouraring
Target: 2,000,000 participants
NCT07267871
Recruiting
The Million Anesthesia Cases Study (MACS) - a Cohort Study of Preoperative Fasting and Perioperative Outcomes
Massachusetts General Hospital
Target: 1,200,000 participants
NCT07022951
Recruiting
Parkinson's Foundation Surveys
Parkinson's Foundation
Target: 1,000,000 participants
NCT05066763
Sponsor volume vs. recruiting share
Among the 20 most active sponsors by total trial count: total trials (x) against the share of those trials currently recruiting (y). Running the most trials overall does not mean the largest share of them is open right now.
Most Studied Conditions
All conditions → Breast Cancer
423 recruiting 1,251
Healthy 225 recruiting 1,096
Obesity 306 recruiting 1,057
Prostate Cancer 275 recruiting 749
Depression 245 recruiting 687
Cancer 279 recruiting 621
HIV Infections 56 recruiting 615
Hypertension 152 recruiting 472
Stroke 218 recruiting 456
Non-Small Cell Lung Cancer 206 recruiting 455
Multiple Myeloma 167 recruiting 441
Lung Cancer 146 recruiting 430
Heart Failure 164 recruiting 399
Colorectal Cancer 162 recruiting 394
Asthma 70 recruiting 378
Most Active Sponsors
All sponsors → National Cancer Institute (NCI) 326 recruiting
3,257 trials Mayo Clinic 544 recruiting
2,844 trials M.D. Anderson Cancer Center 549 recruiting
2,692 trials Massachusetts General Hospital 336 recruiting
2,032 trials National Institute of Allergy and Infectious Diseases (NIAID) 155 recruiting
2,006 trials Memorial Sloan Kettering Cancer Center 327 recruiting
1,884 trials Pfizer 106 recruiting
1,845 trials Stanford University 264 recruiting
1,744 trials Duke University 187 recruiting
1,725 trials University of California, San Francisco 272 recruiting
1,713 trials Trial Status Breakdown
Completed
117,064
Recruiting
24,857
Terminated
19,881
Active (not recruiting)
10,685
Not yet recruiting
3,151
Find Recruiting Trials
Search by condition and US state to find clinical trials currently recruiting participants near you.
Search recruiting trials →Sponsor Pipelines
Explore what pharmaceutical companies and research institutions are testing. Track pipeline activity by therapeutic area.
Browse sponsors →Phase & Condition Data
Understand where research is concentrated. See phase distribution by condition and track research momentum over time.
View rankings →Guides & Analysis
Editorial research and plain-language explainers from our team. Every guide is written to help you read the underlying public data correctly.
Research
Plain-language analysis from our editorial process, built on the public ClinicalTrials.gov registry - PlainTrial research articles.
How to use PlainTrial
Start with your condition, then narrow to what's recruiting near you.
- Search any condition to see every registered trial and its current recruiting status. Browse conditions
- Filter to trials enrolling now, then read each listing for eligibility and study locations. Recruiting trials
- Save trials to a private shortlist in this browser, then compare 2-4 side by side before you talk with your clinician. Open shortlist
- Check which sponsors and US states run the most trials in your area of interest. View rankings
PlainTrial mirrors public ClinicalTrials.gov records for reference only and is not medical advice. Eligibility and enrollment decisions must be made with a licensed healthcare provider.
About this data
How PlainTrial works, and why you can trust these numbers
What this site is
PlainTrial is a plain-language reference for 175,638 US clinical trials, conditions, sponsors, phases, and locations, built from the ClinicalTrials.gov bulk data export. Registry snapshot current as of 2026-08-08.
Editorial process
- Source. Download the ClinicalTrials.gov bulk data export (JSON-formatted study records), the official US registry of publicly and privately supported clinical studies maintained by the National Library of Medicine (NIH).
- Verify. Each study record is submitted by the responsible party and undergoes automated quality checks by the NLM before publication; we present the NCT identifier, phase, status, and condition fields exactly as registered.
- Publish. Trial listings, recruiting status, and condition/sponsor breakdowns are rendered from our snapshot of the bulk export (as of 2026-08-08), with an honest lag disclosed between refreshes.
Editorial independence & corrections
The PlainTrial is independent and not affiliated with ClinicalTrials.gov, the NIH, or the NLM. PlainTrial is an informational resource only, not medical advice, clinical trial eligibility and enrollment decisions must be made with your healthcare provider. Always verify current trial information directly at ClinicalTrials.gov. See our methodology for full source attribution and refresh cadence.
Frequently asked
What data does PlainTrial use?
All data comes from ClinicalTrials.gov (National Library of Medicine), the official US registry for publicly funded and privately funded clinical trials. Data is publicly available and updated regularly.
How do I find a recruiting trial for my condition?
Visit the Recruiting Trials page and filter by condition or state. You can also browse the Conditions directory to find active trials for a specific diagnosis.
Is PlainTrial a substitute for medical advice?
No. PlainTrial is an informational resource only. Clinical trial eligibility and enrollment decisions must be made with your healthcare provider. Never enroll in a clinical trial without professional medical guidance.
What do trial phases mean?
Phase 1 tests safety in a small group; Phase 2 evaluates efficacy and side effects; Phase 3 confirms effectiveness in larger populations; Phase 4 monitors approved treatments.