ClinicalTrials.gov API — Clinical Study Data

What does ClinicalTrials.gov API do?

ClinicalTrials.gov API searches the official ClinicalTrials.gov API and returns current, normalized clinical study data in JSON, CSV, Excel, XML, and other Apify dataset formats. It is a low-friction ClinicalTrials.gov API wrapper for analysts, researchers, data teams, and automation workflows that do not want to maintain pagination and schema-normalization code.

For teams comparing a clinical trials API or a reusable clinical trials data export, this Actor adds Apify scheduling, datasets, webhooks, and integrations around the official source without claiming to replace the source registry.

The Actor uses the official JSON API. It does not scrape pages, use a browser, bypass access controls, provide medical advice, match patients to trials, or extract recruitment contact names, phone numbers, or email addresses.

Why use this ClinicalTrials.gov API Actor?

• Search by condition, general terms, intervention, sponsor, or NCT identifier.
• Filter by location and one or more overall study statuses.
• Receive a stable normalized schema instead of deeply nested source JSON.
• Follow official nextPageToken pagination automatically.
• Stop at a clear maxItems cost boundary of up to 5,000 studies.
• Retry temporary source failures and HTTP 429 responses with bounded backoff.
• Store only successful study records as billable PPE events.
• Export results or connect them to Apify API, schedules, webhooks, Make, Zapier, Google Sheets, or an MCP workflow.
• Keep source attribution and freshness fields in every result.

The Actor is intentionally narrow in its first release. It focuses on reliable study search and data delivery instead of trying to become a patient-recruitment or outreach platform.

ClinicalTrials.gov API comparison: Actor vs direct API

Both routes use the official ClinicalTrials.gov API. The better choice depends on whether you want the complete source contract or a smaller automation-ready dataset.

Decision	This Actor	Direct official API
Best for	Scheduled exports, Apify datasets, webhooks, and no-code integrations	Teams maintaining their own API client and source schema
Pagination	Follows nextPageToken until maxItems is reached	Your client owns pagination and stopping rules
Output	Normalized study subset with source and freshness fields	Full official response, including fields this Actor intentionally omits
Operations	Bounded retries, run metrics, datasets, schedules, and integrations	Your infrastructure owns retries, storage, monitoring, and orchestration
Cost	PPE charge per successfully stored study plus applicable Apify platform usage	Use of the public source API; your team pays its own engineering and infrastructure costs

Use the direct API when you need every source field, FHIR resources, or complete control over the client. Use this Actor when the normalized schema and Apify operations remove more maintenance than they add. Neither route changes the source data or makes a clinical recommendation.

What clinical trial data can it extract?

Field group	Example fields	Description
Identification	nctId, briefTitle, officialTitle, acronym	Public study identifiers and titles
Status and design	overallStatus, studyType, phases, primaryPurpose	Current status and study design summary
Research scope	conditions, interventions, briefSummary	Conditions, intervention names/types, and brief public summary
Organizations	leadSponsor, collaborators	Sponsor and collaborator organizations
Enrollment	enrollmentCount, enrollmentType	Actual or estimated enrollment
Eligibility summary	sex, minimumAge, maximumAge, healthyVolunteers	High-level eligibility fields, not patient-level data
Geography	countries, locations	Facility and geographic fields with contacts removed
Dates and freshness	startDate, completionDate, lastUpdatePostedDate, retrievedAt	Study dates and source freshness metadata
Attribution	sourceName, sourceUrl, termsUrl	Direct source and terms links

How to search ClinicalTrials.gov

1. Open the Actor input tab.
2. Choose whether your query is a condition, any terms, an intervention, a sponsor, or an NCT identifier.
3. Enter the query. For NCT identifiers, you can enter up to 100 IDs separated by commas or whitespace.
4. Optionally enter a location and select overall statuses such as RECRUITING or COMPLETED.
5. Set the maximum number of study records. Start with 10-100 while testing a workflow.
6. Run the Actor and open the dataset in the Output tab.
7. Download the dataset in JSON, HTML, CSV, Excel, XML, or another supported format, or consume it through the Apify API.

Example input:

{
  "searchType": "condition",
  "query": "type 2 diabetes",
  "location": "United States",
  "overallStatuses": ["RECRUITING", "NOT_YET_RECRUITING"],
  "maxItems": 100
}

NCT identifier lookup:

{
  "searchType": "nctId",
  "query": "NCT01234567, NCT07654321",
  "maxItems": 2
}

Input

Field	Type	Default	Description
searchType	string	condition	Interpret the query as a condition, terms, intervention, sponsor, or NCT identifier
query	string	required	Search text or 1-100 NCT identifiers
location	string	empty	Optional city, state, country, or other location text
overallStatuses	array	empty	Optional list of official overall status values
maxItems	integer	25	Maximum successful study records returned and billed, from 1 to 5,000

See the input tab for the complete field descriptions and available status values.

Output

Each successful row is one current ClinicalTrials.gov study record:

{
  "recordType": "study",
  "searchType": "condition",
  "searchQuery": "type 2 diabetes",
  "nctId": "NCT01234567",
  "briefTitle": "Example study of a new intervention",
  "overallStatus": "RECRUITING",
  "studyType": "INTERVENTIONAL",
  "phases": ["PHASE2"],
  "conditions": ["Type 2 Diabetes"],
  "interventions": [
    {"type": "DRUG", "name": "Example intervention"}
  ],
  "leadSponsor": {
    "name": "Example University",
    "partyClass": "OTHER"
  },
  "enrollmentCount": 120,
  "countries": ["United States"],
  "lastUpdatePostedDate": "2026-07-10",
  "sourceName": "ClinicalTrials.gov",
  "sourceUrl": "https://clinicaltrials.gov/study/NCT01234567",
  "retrievedAt": "2026-07-14T12:00:00Z"
}

The OUTPUT record in the default key-value store reports the source status, total matches when supplied by the API, studies stored, pages requested, retries, 429 responses, downloaded bytes, billable events, charge-limit state, runtime, and freshness timestamps.

How much does ClinicalTrials.gov API cost?

The launch list price is $0.003 per successfully stored study, or $3 per 1,000 studies. Store-plan volume discounts reduce the result price to as little as $0.0021 per study. Empty searches, retries, source errors, and summary records do not emit the study-result billing event. Apify manages its synthetic apify-actor-start event for PPE Actors. Platform-usage pass-through is not enabled.

Examples at list price:

Successful studies	Result charge
100	$0.30 + $0.00005 start
1,000	$3.00 + $0.00005 start
5,000 maximum	$15.00 + $0.00005 start

The Store pricing configuration is authoritative. Check the pricing tab before running a large job. Re-running the same query can return and bill the same studies again because deduplication applies only to the current API response and run.

Validation evidence (2026-07-14)

Validation on 2026-07-14 established the following bounded facts:

• The official API documentation and Terms and Conditions endpoints returned HTTP 200.
• The live Apify Store surface returned HTTP 200 and exposed the Actor title, description, README, and PPE study-result pricing.
• Nine focused release tests passed for query construction, pagination, contact omission, normalization, successful-result billing, charge limits, retries, and output summaries.
• The local strict Actor checks passed for schemas, Docker configuration, PPE declarations, links, metadata, and secret scanning before the release was deployed.

This evidence verifies the release contract and Store readiness; it does not claim organic rankings, search traffic, external reviews, or citation by an AI answer engine. Source behavior, Store pricing, and terms can change, so verify the linked official pages and the current pricing tab for high-impact workflows.

Tips and limitations

• Start with a small maxItems value to verify a query before scheduling it.
• Use status filters to reduce result volume for recruitment or completed-study research.
• Use lastUpdatePostedDate and retrievedAt to decide whether a downstream copy is current enough for your workflow.
• The Actor requests pages sequentially and does not use proxies or rotate identities.
• A source outage, schema change, or sustained rate limit can produce partial results or a failed run. Partial data already stored remains available.
• ClinicalTrials.gov is updated daily and does not guarantee that sponsor-submitted data are complete or error-free.
• This Actor is not a historical archive and does not guarantee that a record remains unchanged between runs.
• The Actor does not download study documents, expand FHIR resources, deliver webhooks, or persist a change-monitoring database in this release.

FAQ, terms, and responsible use

Is this an official ClinicalTrials.gov product?

No. This independent Actor uses the official public API but is not affiliated with or endorsed by ClinicalTrials.gov, NIH, NLM, HHS, or the United States Government.

Can I use the output for patient matching or medical advice?

No. The data are study-registry records, not medical advice or a clinical recommendation. Validate important information with the official study record and qualified professionals.

Does it return recruitment contacts or emails?

No. Contact names, phone numbers, and email addresses are intentionally omitted. The ClinicalTrials.gov terms prohibit using extracted email addresses for marketing or promotional purposes.

What source attribution applies?

ClinicalTrials.gov states that distributed data should attribute ClinicalTrials.gov, remain current, and display the ClinicalTrials.gov processing date. Every row includes sourceName, sourceUrl, lastUpdatePostedDate, retrievedAt, and the official terms URL. You are responsible for following the current ClinicalTrials.gov Terms and Conditions in your downstream use.

Does the Actor own or relicense the source database?

No. The Actor only transforms current API responses into a convenient schema. Do not assert proprietary rights over the ClinicalTrials.gov database or present it as anything other than a United States Government database. Some submitted content may include third-party rights.

What about personal data?

The Actor excludes recruitment contacts, but study locations and organization names can still relate to real-world institutions and people. Process all output for a legitimate purpose and follow applicable privacy, research, and data-protection requirements. If you are unsure, consult qualified legal or compliance advisers.

Support

When reporting an issue, include the run ID, sanitized input, expected NCT identifier or filter behavior, and the visible error message. Do not send patient data, credentials, private research records, or recruitment contact lists.