Clinical trials & studies
Search clinical trials and observational studies from US and EU trial registries, each with its recruitment status, phase, design, conditions, interventions, outcome measures, eligibility and sponsors.
This study will look at the change in participants' body weight from the start to the end of the study…
What's in the dataset
One page per study
A study registered in more than one registry gets one page that lists every registry number, each linked to the registry's own record.
Status and dates
Recruitment status, registration date, start and completion dates, and enrollment.
Design
Phase, allocation, masking and arms for trials. Observational model and time perspective for observational studies.
Conditions and interventions
The conditions studied and the drugs, devices or procedures tested, with their medical codes.
Outcomes and eligibility
Primary and secondary outcome measures, and who can take part.
Sponsors and sites
Sponsor, collaborators, investigators, study sites and recruitment countries.
Search by what matters
Describe the study in plain language, or search by condition, intervention, sponsor or registry number. To keep results to clinical study pages, add includeDomains: ["exa.ai/library/health/study"].
Read the docs →# Same endpoint and API key as web search
curl https://api.exa.ai/search \
-H "x-api-key: $EXA_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"query": "recruiting phase 2 trials for early Alzheimer's disease",
"includeDomains": ["exa.ai/library/health/study"],
"contents": { "text": true }
}'What teams build with it
Clinical research agents
Find the trials behind a drug, device or condition from a plain-language question.
Competitive intelligence
See what a sponsor is testing, in which phase and in which countries.
Medical RAG
Ground answers in the registry record, with its design, outcome measures and eligibility criteria.
Searchable alongside the general web index
Clinical trials live in the same index as the open web. There's no separate API or integration: use the same /search endpoint and API key you already use.
Query clinical trials on their own, or mix them with web results in a single call.
Common questions
Which trial registries does Exa cover?
ClinicalTrials.gov and the EU Clinical Trials Information System (CTIS).
Are observational studies included?
Yes. The collection covers interventional clinical trials and observational studies.
What's on a clinical trial page?
The study's titles, registry numbers, recruitment status, key dates, phase, design, arms, conditions, interventions, outcome measures, eligibility, enrollment, sponsors, investigators, sites and the results publications its registry lists.
Does a page include the study's results?
No. A page is the registry record of the study. It says whether results are posted in the registry and lists the results publications the registry links.
Is there a clinical trials API?
Yes. Clinical trials are searchable through the same Exa /search endpoint and API key you use for web search, so there's no separate API to set up.
How do I search only clinical trials?
Pass includeDomains: ["exa.ai/library/health/study"] to the /search endpoint.
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Start searching clinical trials
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