Clinical Trial Success Rates
Historical success rates for clinical trials by development phase, based on primary endpoint achievement data from our database.
| Phase | Total Trials | Successful | Primary-Endpoint Met |
|---|---|---|---|
| Early Phase 1 | 1 | 1 | n too small |
| Phase 1 | 17 | 2 | n too small |
| Phase 1/Phase 2 | 24 | 2 | n too small |
| Phase 2 | 244 | 89 | 36.5% |
| Phase 2/Phase 3 | 29 | 14 | n too small |
| Phase 3 | 384 | 261 | 68% |
| Phase 4 | 38 | 20 | 52.6% |
Understanding Trial Success Rates
The table above shows, for each phase, the share of trials in BioSniper's database with posted results that met their primary endpoint. Rates are only reported where the sample is large enough to be reliable (n ≥ 30); smaller samples are marked n too small rather than shown as a misleading percentage.
For broader context, industry-wide transition benchmarks from published research (e.g. BIO/Informa Clinical Development Success Rates) show approximately:
- Phase 1 → Phase 2: ~52-65% (primarily safety)
- Phase 2 → Phase 3: ~28-35% (efficacy signal)
- Phase 3 → Approval: ~55-60% (pivotal efficacy)
- Overall (Phase 1 → Approval): ~7-12%
Note these benchmarks measure phase-to-phase transition (a different metric from the primary-endpoint-met rate in our table), and vary by therapeutic area — oncology trends lower while rare/orphan diseases often run higher.
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