ClinicalTrials.gov API — clinical studies search (no key)

Search the official ClinicalTrials.gov registry — 500,000+ clinical studies — behind a clean HTTP API (and MCP tool). Find trials by condition, intervention/drug, sponsor, location and recruitment status, and pull full study detail by NCT id (summary, eligibility, outcomes, arms, sponsor, locations). Built for pharma & biotech research, health tech, patient tools, journalism and agents. No API key. Pay per query.

• 🔎 Search — by condition, intervention, sponsor, location and status; sort by relevance or most-recently-updated.
• 🧪 Study detail — NCT id → brief summary, phases, eligibility (sex, age, healthy volunteers), primary outcomes, arms, sponsor, collaborators, locations.
• 🏥 Recruitment status — filter for RECRUITING, COMPLETED, TERMINATED and more.
• 🇺🇸 Official & keyless — straight from ClinicalTrials.gov's v2 API.
• 💵 Pay per query.

The use case it was built for

"Which recruiting trials target NASH, and who's sponsoring them?" — one call returns clean, typed rows; another returns the full protocol for a specific NCT. Perfect for competitive intelligence, patient-matching, systematic reviews and health agents.

Sample output (search, condition "diabetes", status RECRUITING)

{
  "ok": true, "totalCount": 1956, "count": 1,
  "studies": [
    { "nctId": "NCT07758582", "title": "Validation of the AI Subsystem of the D…",
      "status": "RECRUITING", "phases": [], "conditions": ["Diabetic Retinopathy"],
      "interventions": ["…"], "leadSponsor": "…", "locationsCount": 3,
      "url": "https://clinicaltrials.gov/study/NCT07758582" }
  ]
}

How to use

• HTTP API (Standby): POST or GET /search, /study. GET / returns help. Example: GET /search?condition=melanoma&status=RECRUITING.
• Normal run: pass { operation, condition | nctId, ... }; results land in the dataset + key-value store.
• MCP tool: expose it to your agent via Apify's MCP server.

Input

• operation — search · study.
• condition / intervention / term / sponsor / location — search filters (combine any).
• status — recruitment statuses (e.g. ["RECRUITING"]). sort — relevance / recent. limit — cap studies.
• nctId — for study (e.g. NCT00841061).

Pricing

Per query from $0.005 (down to $0.0015 on higher tiers). One call = one query (search returns many studies at once).

Related Actors

• openFDA Drugs — drug labels, adverse events and recalls.
• Crossref API — scholarly papers and DOI metadata.

FAQ

Do I need a key? No — ClinicalTrials.gov's v2 API is keyless.

Which statuses can I filter by? RECRUITING, NOT_YET_RECRUITING, ACTIVE_NOT_RECRUITING, COMPLETED, ENROLLING_BY_INVITATION, SUSPENDED, TERMINATED, WITHDRAWN and more.

How fresh is the data? ClinicalTrials.gov is updated continuously as sponsors submit and revise records.

Notes & limits

Data from the U.S. National Library of Medicine's ClinicalTrials.gov (api v2). Up to 100 studies per search call; use filters to focus. This is registry metadata, not medical advice.