clinicaltrialsgov-mcp-server

Overview

A comprehensive MCP server for accessing ClinicalTrials.gov v2 API functionality. It offers seven distinct tools for searching clinical trials, retrieving detailed study information, fetching study results, matching patients to eligible trials, and exploring field values and definitions. Built with TypeScript and based on the @cyanheads/mcp-ts-core framework, it provides both stdio and Streamable HTTP transport options. The server includes proper error handling, rate limiting, retry mechanisms, and supports authentication for HTTP transport.

Try asking AI

After installing, here are 5 things you can ask your AI assistant:

• clinicaltrials_search_studies

  Search studies with full-text queries, filters, pagination, sorting, and field selection.

  Try:Find clinical trials for breast cancerTry:Search for trials testing new diabetes medicationsTry:Show me all HIV trials in California
• clinicaltrials_get_study_record

  Fetch a single study by NCT ID. Returns the full record: protocol, eligibility, outcomes, arms, interventions, contacts, and locations.

  Try:Get details for study NCT04704795Try:Retrieve record for NCT03866330Try:Show me the full study information for NCT04881230
• clinicaltrials_get_study_count

  Get total study count for a query without fetching data. Fast statistics and breakdowns.

  Try:How many studies are there for Alzheimer's?Try:Count all Phase 3 cancer trialsTry:Get total number of COVID-19 vaccine trials
• clinicaltrials_get_field_values

  Discover valid values for API fields (status, phase, study type, etc.) with per-value counts.

  Try:What study statuses are available?Try:Show me all possible trial phasesTry:List all study types in the database
• clinicaltrials_get_field_definitions

  Browse the study data model field tree — piece names, types, nesting. Supports subtree navigation and keyword search.

  Try:What fields are available for eligibility criteria?Try:Show me all fields related to study outcomesTry:Browse the data model for intervention fields
• clinicaltrials_get_study_results

  Extract outcomes, adverse events, participant flow, and baseline from completed studies. Optional summary mode reduces ~200KB payloads to ~5KB.

  Try:Get results for NCT04704795Try:Fetch adverse events for study NCT03866330Try:Show summary results for completed COVID-19 vaccine trials
• clinicaltrials_find_eligible

  Match patient demographics and conditions to eligible recruiting trials.

  Try:Find trials for a 45-year-old male with type 2 diabetesTry:Match a patient with asthma to suitable clinical trialsTry:Find recruiting trials for a 60-year-old woman with breast cancer

Comparable tools

Installation

{
  "mcpServers": {
    "clinicaltrialsgov-mcp-server": {
      "type": "streamable-http",
      "url": "https://clinicaltrials.caseyjhand.com/mcp"
    }
  }
}

{
  "mcpServers": {
    "clinicaltrialsgov-mcp-server": {
      "type": "stdio",
      "command": "bunx",
      "args": ["clinicaltrialsgov-mcp-server@latest"],
      "env": {
        "MCP_TRANSPORT_TYPE": "stdio"
      }
    }
  }
}

FAQ

Is an API key required to use this server?

No, the ClinicalTrials.gov API is public and doesn't require authentication or API keys.

Can I use this server with Claude Desktop?

Yes, you can configure it via stdio transport or use the public HTTP endpoint.

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