ClinicalTrials.gov Full registry of interventional clinical trials with protocol metadata, endpoints, and enrollment data | Active | Tier 1 - Government Registry | Weekly | Mar 30, 2026 | 48,231 | |
PubMed / PMC Biomedical literature database and full-text repository from the National Library of Medicine | Active | Tier 1 - Peer-Reviewed Literature | Daily | Mar 31, 2026 | 127,845 | |
FDA Guidance Library FDA guidance documents, draft guidances, and regulatory communications for drug development | Active | Tier 1 - Regulatory Authority | Monthly | Mar 15, 2026 | 3,412 | |
ChEMBL Open-access bioactivity database of drug-like small molecules and their biological targets | Active | Tier 2 - Curated Database | Quarterly | Jan 15, 2026 | 15,678 | |
OpenFDA FDA open data API providing access to drug adverse events, labels, and enforcement reports | Paused | Tier 1 - Regulatory Authority | Weekly | Mar 20, 2026 | 8,934 | |