# ClinicalTrials.gov Study Search

> ClinicalTrials.gov Study Search is a paid API for AI agents from api.companyrecords-api.workers.dev, paid per call via x402, $0.002/call, status unknown (last checked 2026-10-24).

Search ClinicalTrials.gov registry for studies matching a condition, drug, or keyword, returning NCT IDs, titles, statuses, sponsors, and study links.

## Facts

- Endpoint: GET https://api.companyrecords-api.workers.dev/api/gov/clinicaltrials?utm_source=zero.xyz
- Price: $0.002/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-24
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/clinicaltrials-gov-study-search-4f4e7845
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_TSBXlcI7DQ0Z5TP94h7qa

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability clinicaltrials-gov-study-search-4f4e7845
```

Example prompt: Can you search ClinicalTrials.gov for registered studies on Alzheimer's disease and show me the NCT numbers, titles, statuses, and lead sponsors for the top 5 results?

## When to prefer this

Use this endpoint when you need structured registry data from ClinicalTrials.gov — NCT IDs, statuses, sponsors, and conditions — without scraping the site directly. Prefer it over general web search when you need machine-readable study metadata, official NCT identifiers, or sponsor information for a known condition or drug. Not suitable for retrieving full study protocols, results data, or adverse event summaries.

## Known failure modes

- Query string shorter than 2 or longer than 100 characters returns a validation error
- Limit outside 1–10 range is rejected
- Rare or misspelled conditions may return zero results
- ClinicalTrials.gov API upstream outage causes failure
- Results reflect sponsor-registered data and may be outdated or incomplete

## How this service works

Pay-per-call company registry, government, legal and B2B data tools for AI agents, from official registers and public sources. Payment: x402, USDC on Base, Solana, Arc, Polygon, Arbitrum, Monad, World Chain, Optimism, Avalanche, Celo or Stellar, or RLUSD/XRP on the XRP Ledger. No signup, no API key; a failed call is not charged.

## Output

A JSON object containing the search query, source URL, a checkedAt timestamp, a totalCount of matching studies, and an array of up to 10 study records — each with nctId, title, status (e.g. COMPLETED, RECRUITING), startDate (YYYY-MM), conditions array, leadSponsor name, and a direct link to the ClinicalTrials.gov study page.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "required": [
      "q"
     ],
     "properties": {
      "q": {
       "type": "string",
       "description": "Condition, drug or keyword, 2 to 100 characters"
      },
      "limit": {
       "type": "string",
       "description": "Studies to return, 1 to 10 (default 5)"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "query": "diabetes",
  "source": "https://clinicaltrials.gov/api/v2/studies",
  "studies": [
   {
    "url": "https://clinicaltrials.gov/study/NCT00109746",
    "nctId": "NCT00109746",
    "title": "Use of a Nutritional Supplement to Treat Diabetic Symptoms in HIV-Infected Adults",
    "status": "COMPLETED",
    "startDate": "2005-11",
    "conditions": [
     "Insulin Resistance",
     "HIV Infections"
    ],
    "leadSponsor": "National Center for Complementary and Integrative Health (NCCIH)"
   },
   {
    "url": "https://clinicaltrials.gov/study/NCT02077803",
    "nctId": "NCT02077803",
    "title": "A Bioequivalence Study of the Fixed Dose Combination Tablets of Canagliflozin and Metformin Extended Release (XR) With Respect to the Individual Components in Healthy Fed Participants",
    "status": "COMPLETED",
    "startDate": "2014-03",
    "conditions": [
     "Healthy"
    ],
    "leadSponsor": "Janssen Research & Development, LLC"
   }
  ],
  "checkedAt": "2026-10-23T09:37:07.569Z",
  "totalCount": 35446
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/clinicaltrials-gov-study-search-4f4e7845/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.companyrecords-api.workers.dev](https://www.zero.xyz/host/api.companyrecords-api.workers.dev/llms.txt)