Search ClinicalTrials.gov — every registered US (and many international) clinical study (~500k trials). Free-text query matches title + condition + intervention; or direct lookup by NCT ID. Optional filters: recruitment status, lead sponsor, phase (PHASE1..PHASE4), country. Each record includes NCT ID, brief + official title, status, phases, study type, conditions list, interventions (with type + name), enrollment count + type, key dates (start / primary completion / completion / first posted / last update), lead sponsor + class (INDUSTRY/NIH/OTHER), hasResults flag, brief summary, and canonical clinicaltrials.gov URL. Public-domain NIH NLM data.