Clinical Trials - ClinicalTrials.gov Registry

Search the official US clinical trial registry and get clean, flat rows.

ClinicalTrials.gov holds every registered study: what is being tested, on whom, by whom, where, and how it turned out. The registry returns deeply nested JSON. This Actor flattens it into one row per trial, with the fields people actually filter and sort on already pulled out.

No API key needed. It works out of the box.

What you get

Field	Description
nctId / url	Registry ID and a direct link
title / officialTitle / acronym	Short and full titles
status / isRecruiting	Recruitment status, plus a flag for the common case
phases	PHASE1 through PHASE4, or NA where phase does not apply
studyType	Interventional, observational or expanded access
conditions	Diseases being studied
interventionNames / interventionTypes	Drugs, devices or procedures tested
primaryOutcome	The endpoint the trial is designed to measure
leadSponsor / leadSponsorClass / isIndustrySponsored	Who runs it, and whether it is commercial
collaborators	Other organisations involved
enrollment / enrollmentIsActual	Participant count, and whether it is a target or the real figure
siteCount / countries / countryCount	Geographic footprint of the trial
startDate / primaryCompletionDate / completionDate	Timeline, with flags for actual versus estimated
minimumAge / maximumAge / sex / acceptsHealthyVolunteers	Eligibility at a glance
hasResults	Whether results have been posted
isFdaRegulatedDrug / isFdaRegulatedDevice	FDA oversight flags

Example input

Recruiting Phase 2 and 3 breast cancer trials:

{
  "conditions": ["breast cancer"],
  "overallStatus": ["RECRUITING"],
  "phases": ["PHASE2", "PHASE3"],
  "studyType": "INTERVENTIONAL",
  "maxResults": 500
}

Everything one company is running:

{
  "sponsorName": "Pfizer",
  "overallStatus": ["RECRUITING", "ACTIVE_NOT_RECRUITING"]
}

Trials recruiting in a given country:

{
  "locationTerm": "Korea",
  "overallStatus": ["RECRUITING"]
}

Example output

{
  "nctId": "NCT07391774",
  "url": "https://clinicaltrials.gov/study/NCT07391774",
  "title": "Testing Whether Hormone Therapy With Ribociclib is as Effective as Chemotherapy...",
  "status": "RECRUITING",
  "isRecruiting": true,
  "phases": "PHASE3",
  "studyType": "INTERVENTIONAL",
  "conditions": "Anatomic Stage II Breast Cancer AJCC v8",
  "leadSponsor": "National Cancer Institute (NCI)",
  "leadSponsorClass": "NIH",
  "isIndustrySponsored": false,
  "enrollment": 1978,
  "enrollmentIsActual": false,
  "siteCount": 312,
  "countries": "United States, Canada",
  "startDate": "2026-03-16"
}

What people use it for

• Competitive intelligence - what a rival is running, in which phase, and how big
• Site and investigator targeting - which centres run trials in your therapeutic area
• Patient recruitment - recruiting studies by condition and location
• Market sizing - enrolment and trial counts by indication over time
• Research and journalism - a citable public source, updated daily

Notes

• Several search terms in one field are combined with OR, so ["breast cancer", "ovarian cancer"] returns both.
• Search is not exact matching. A study can match on its title or an eligibility detail rather than its condition list, so a small share of rows will not repeat your keyword in the conditions field.
• List fields such as conditions and countries are joined with commas so the output stays flat and drops straight into a spreadsheet.
• Dates can be month-precision (2026-03) where the registry has no day. They are passed through as recorded rather than padded to a false precision.
• enrollmentIsActual and the date IsActual flags distinguish planned figures from what really happened. Ignoring them mixes forecasts with facts.
• Source: ClinicalTrials.gov, U.S. National Library of Medicine. Registry content is public domain.

Pricing

Pay per result. You are charged only for studies actually returned.