TriangleHow to read a ClinicalTrials.gov listing
Every trial on this site links to its registry record. Ten minutes with that page answers most first questions.
This is not clinical evidence and not medical advice. It does not replace your care team. Discuss anything here with your clinician before you act on it. Product questions are on the FAQ.
ClinicalTrials.gov is where a study is described before it enrols anyone. The responsible party, usually the sponsor, enters the record. Our Phase 1 pages are built from those records. I print the listing and take it to the consult so we are looking at the same page.
The NCT number
NCT plus eight digits. Assigned when the study is registered, never reused. A drug name can belong to several studies; an NCT number belongs to one. Use it when you call a clinic or talk to your oncologist.
Status, contacts, and how stale the page is
Recruiting: enrolling now. Not yet recruiting: registered, not started. Active, not recruiting: people are still being treated or followed, but they are not taking anyone new. Unknown: the record passed its own completion date without being updated, so treat the status as possibly stale.
Contact information appears only while a study is recruiting or not yet recruiting. Once it is active but no longer recruiting, or completed, the registry strips the contacts. An empty contact field is usually that, not a broken page.
Last update posted is the date the sponsor last changed the record. A recent date means someone is maintaining it. An old date does not prove the study is closed, but it is a reason to confirm by phone before you book a flight.
Eligibility
Most records split this into inclusion (what you must have) and exclusion (what rules you out). The lists are written for clinicians and they run long. Read them with your oncologist. A single line about prior treatment or a lab value is often what decides whether a study is open to you.
The registry describes the plan. It does not say whether the treatment helps, whether a particular site has a slot this month, or whether you personally qualify. Those go to the study contact and to your own clinician.
See recruiting Phase 1 trials →
Sources
- ClinicalTrials.gov: How to Read a Study RecordThe ClinicalTrials.gov ID (NCT number) is assigned at registration; the record shows sponsor, responsible party, and Last Update Posted date.
- ClinicalTrials.gov: How to Read a Study Record — Study statusDefinitions of Recruiting, Not yet recruiting, Active not recruiting, and Unknown study statuses.
- ClinicalTrials.gov: How to Read a Study Record — Participation CriteriaParticipation criteria are shown as inclusion criteria and exclusion criteria.
- ClinicalTrials.gov: How to Read a Study Record — Contacts and LocationsContact information is listed only for studies that are Not yet recruiting or Recruiting; none is listed for Active not recruiting, Completed, Terminated, Enrolling by invitation, Suspended, or Withdrawn.
- NCI: How Do Clinical Trials Work?Every trial has eligibility criteria, and they are written to reduce medical differences among participants and limit risk.