What is a primary completion date (on ClinicalTrials.gov)?
The registered date when a trial's final participant is examined for the primary endpoint.
Every registered trial declares a primary completion date. It is the best public estimate of when data could exist — but sponsors routinely let the date slip as enrollment lags.
We track these dates and diff every change to them. A slip of more than six months without explanation is a classic quiet negative signal.
See it live: the catalyst calendar · status-change feed