fourzerotwo-si

fourzerotwo-si Clinical Trials API

Clinical Trials (ClinicalTrials.gov): Search 500,000+ registered clinical studies by condition, drug, sponsor, place, status and phase; full study records and recruitment counts.

Documentation GitHub OpenAPI

Operations 4

GET /v1/clinical-trials/search Clinical Trials (ClinicalTrials.gov): Search clinical trials #

GET /v1/clinical-trials/study Clinical Trials (ClinicalTrials.gov): Study by NCT number #

GET /v1/clinical-trials/recruiting Clinical Trials (ClinicalTrials.gov): Recruiting trials near a place #

GET /v1/clinical-trials/stats Clinical Trials (ClinicalTrials.gov): Trial counts by status #

Specifications

⚙

OpenAPI

https://artifacts.apis.io/fourzerotwo-si/openapi/fourzerotwo-si-clinical-trials-api-openapi.yml

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OpenAPI Specification

openapi: 3.2.0
info:
  title: Fourzerotwo Si Clinical Trials API
  version: 1.1.0
  contact:
    url: https://fourzerotwo.si
  description: 'Operations tagged clinical-trials across 2 of this provider''s published API definitions: openapi.json, fourzerotwo-si-openapi.json. Each path carries the servers of the definition it was published in.'
servers:
- url: https://fourzerotwo.si
tags:
- name: clinical-trials
  description: 'Clinical Trials (ClinicalTrials.gov): Search 500,000+ registered clinical studies by condition, drug, sponsor, place, status and phase; full study records and recruitment counts.'
paths:
  /v1/clinical-trials/search:
    get:
      operationId: clinical_trials__search
      summary: 'Clinical Trials (ClinicalTrials.gov): Search clinical trials'
      description: 'Find studies by condition, intervention (drug/device), location, sponsor or free text, optionally filtered by status and phase. Price: $0.003 USDC per call via x402. Free within the daily allowance with a free key.'
      tags:
      - clinical-trials
      externalDocs:
        url: https://fourzerotwo.si/apis/clinical-trials/search
      parameters:
      - name: condition
        in: query
        required: false
        description: Condition or disease, e.g. "type 2 diabetes"
        schema:
          type: string
          maxLength: 200
        example: asthma
      - name: intervention
        in: query
        required: false
        description: Drug, device or procedure
        schema:
          type: string
          maxLength: 200
      - name: location
        in: query
        required: false
        description: City, region or country
        schema:
          type: string
          maxLength: 200
      - name: sponsor
        in: query
        required: false
        description: Sponsor or collaborator
        schema:
          type: string
          maxLength: 200
      - name: q
        in: query
        required: false
        description: Free-text search across the record
        schema:
          type: string
          maxLength: 200
      - name: status
        in: query
        required: false
        description: 'Comma-separated: RECRUITING, NOT_YET_RECRUITING, ACTIVE_NOT_RECRUITING, COMPLETED, TERMINATED…'
        schema:
          type: string
          maxLength: 200
        example: RECRUITING
      - name: phase
        in: query
        required: false
        description: 1, 2, 3, 4, EARLY_PHASE1 or NA
        schema:
          type: string
          maxLength: 20
      - name: limit
        in: query
        required: false
        description: Results per page, 1-50 (default 20)
        schema:
          type: integer
        example: 10
      - name: page_token
        in: query
        required: false
        description: next_page_token from a previous response
        schema:
          type: string
          maxLength: 200
      responses:
        '200':
          description: The data (paid, or free tier).
          content:
            application/json: {}
        '402':
          $ref: '#/components/responses/PaymentRequired'
        '400':
          $ref: '#/components/responses/Error'
        '404':
          $ref: '#/components/responses/Error'
        '502':
          $ref: '#/components/responses/Error'
      security:
      - {}
      - freeKey: []
      x-price-usd: '0.003000'
      x-free-tier: free
      x-mcp-tool: clinical-trials__search
    servers:
    - url: https://fourzerotwo.si
  /v1/clinical-trials/study:
    get:
      operationId: clinical_trials__study
      summary: 'Clinical Trials (ClinicalTrials.gov): Study by NCT number'
      description: 'One study: title, status, phase, conditions, interventions, sponsor, enrolment, dates, eligibility basics, primary outcomes, countries, whether results are posted. Price: $0.002 USDC per call via x402. Free within the daily allowance with a free key.'
      tags:
      - clinical-trials
      externalDocs:
        url: https://fourzerotwo.si/apis/clinical-trials/study
      parameters:
      - name: nct_id
        in: query
        required: true
        description: NCT number
        schema:
          type: string
          maxLength: 11
        example: NCT04368728
      responses:
        '200':
          description: The data (paid, or free tier).
          content:
            application/json: {}
        '402':
          $ref: '#/components/responses/PaymentRequired'
        '400':
          $ref: '#/components/responses/Error'
        '404':
          $ref: '#/components/responses/Error'
        '502':
          $ref: '#/components/responses/Error'
      security:
      - {}
      - freeKey: []
      x-price-usd: '0.002000'
      x-free-tier: free
      x-mcp-tool: clinical-trials__study
    servers:
    - url: https://fourzerotwo.si
  /v1/clinical-trials/recruiting:
    get:
      operationId: clinical_trials__recruiting
      summary: 'Clinical Trials (ClinicalTrials.gov): Recruiting trials near a place'
      description: 'Studies recruiting (or about to) for a condition in a city, region or country, with the matching trial sites. Price: $0.003 USDC per call via x402. Free within the daily allowance with a free key.'
      tags:
      - clinical-trials
      externalDocs:
        url: https://fourzerotwo.si/apis/clinical-trials/recruiting
      parameters:
      - name: condition
        in: query
        required: true
        description: Condition or disease
        schema:
          type: string
          maxLength: 200
        example: breast cancer
      - name: location
        in: query
        required: true
        description: City, region or country
        schema:
          type: string
          maxLength: 200
        example: London
      - name: limit
        in: query
        required: false
        description: Results per page, 1-50 (default 20)
        schema:
          type: integer
        example: 10
      - name: page_token
        in: query
        required: false
        description: next_page_token from a previous response
        schema:
          type: string
          maxLength: 200
      responses:
        '200':
          description: The data (paid, or free tier).
          content:
            application/json: {}
        '402':
          $ref: '#/components/responses/PaymentRequired'
        '400':
          $ref: '#/components/responses/Error'
        '404':
          $ref: '#/components/responses/Error'
        '502':
          $ref: '#/components/responses/Error'
      security:
      - {}
      - freeKey: []
      x-price-usd: '0.003000'
      x-free-tier: free
      x-mcp-tool: clinical-trials__recruiting
    servers:
    - url: https://fourzerotwo.si
  /v1/clinical-trials/stats:
    get:
      operationId: clinical_trials__stats
      summary: 'Clinical Trials (ClinicalTrials.gov): Trial counts by status'
      description: 'How many registered studies for a condition are recruiting, active, completed, terminated or withdrawn. Price: $0.003 USDC per call via x402. 3 free calls/day with a free key.'
      tags:
      - clinical-trials
      externalDocs:
        url: https://fourzerotwo.si/apis/clinical-trials/stats
      parameters:
      - name: condition
        in: query
        required: true
        description: Condition or disease
        schema:
          type: string
          maxLength: 200
        example: migraine
      responses:
        '200':
          description: The data (paid, or free tier).
          content:
            application/json: {}
        '402':
          $ref: '#/components/responses/PaymentRequired'
        '400':
          $ref: '#/components/responses/Error'
        '404':
          $ref: '#/components/responses/Error'
        '502':
          $ref: '#/components/responses/Error'
      security:
      - {}
      - freeKey: []
      x-price-usd: '0.003000'
      x-free-tier: sample
      x-mcp-tool: clinical-trials__stats
    servers:
    - url: https://fourzerotwo.si
components:
  responses:
    PaymentRequired:
      description: x402 payment required. The body (also base64 in the PAYMENT-REQUIRED header) lists accepted payments.
      headers:
        PAYMENT-REQUIRED:
          schema:
            type: string
          description: Base64 JSON x402 v2 PaymentRequired
      content:
        application/json:
          schema:
            type: object
            properties:
              x402Version:
                type: integer
              error:
                type: string
              accepts:
                type: array
                items:
                  type: object
    Error:
      description: 400 = invalid input, 404 = not found at the source, 502 = the source failed. Never charged.
      content:
        application/json:
          schema:
            type: object
            properties:
              error:
                type: string
              charged:
                type: boolean
  securitySchemes:
    freeKey:
      type: apiKey
      in: header
      name: X-API-Key
      description: Optional free key (fzt_…) for the free tier.
x-refined-from:
- openapi.json
- fourzerotwo-si-openapi.json