Clinical Trials in Tokyo, 2026
Every study on the ClinicalTrials.gov registry that lists a site in Japan and is open, about to open, active-but-closed, or enrolling by invitation. Filter it, cite it, and take it away as a file.
About this register
This register is built from ClinicalTrials.gov, the trial registry run by the U.S. National Library of Medicine. It includes every study on the registry that lists at least one investigative site in Japan and is recruiting, not yet recruiting, active but no longer recruiting, or enrolling by invitation: 2,493 studies in total at the last sync on 22 Oct 2026, 03:19 UTC. The full list can be downloaded as CSV or queried as JSON through the register API.
This page shows the 15 of those studies with a site in Tokyo that also match the filters currently applied.
How many clinical trials are recruiting in Tokyo?
13 of the 15 studies on this page are recruiting new participants as of the 22 Oct 2026, 03:19 UTC sync. A further 0 have not yet opened recruitment, 2 are active but closed to new participants, and 0 are enrolling by invitation only. Eligibility for any study is decided by its study team.
Summary by phase
| Phase | Studies | Recruiting | Share |
|---|---|---|---|
| Observational | 12 | 10 | 80% |
| Phase 2 | 2 | 2 | 13.3% |
| Phase 3 | 1 | 1 | 6.7% |
Most active sponsors
| Lead sponsor | Studies | Recruiting |
|---|---|---|
| Takeda | 15 | 13 |
Other trial registries in Japan
This register lists Japan studies from ClinicalTrials.gov. Many studies in Japan are registered only in a national registry. We do not copy those records; search them directly:
- jRCT (Japan Registry of Clinical Trials) — run by the Ministry of Health, Labour and Welfare; trials under Japan's Clinical Trials Act and other clinical research
- UMIN-CTR — run by the University of Tokyo Hospital's UMIN Center; many academic and investigator-led studies