Breast Neoplasms Trials in the UK, 2026
Every industry-sponsored study on the ClinicalTrials.gov registry that lists a UK site and is open, about to open, active-but-closed, or enrolling by invitation. This deliberately excludes academic and other non-industry sponsors — the full UK registry across all sponsors is far larger. UK studies may also be registered separately on ISRCTN.
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 industry-sponsored study on the registry that lists at least one investigative site in the UK and is recruiting, not yet recruiting, active but no longer recruiting, or enrolling by invitation: 2,863 studies in total at the last sync on 11 Oct 2026, 03:15 UTC. Academic and other non-industry sponsors are out of scope by design. The full list can be downloaded as CSV or queried as JSON through the register API.
This page shows the 13 of those studies listing the condition Breast Neoplasms.
How many Breast Neoplasms trials are recruiting in the UK?
8 of the 13 studies on this page are recruiting new participants as of the 11 Oct 2026, 03:15 UTC sync. A further 0 have not yet opened recruitment, 5 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 |
|---|---|---|---|
| Phase 3 | 7 | 5 | 53.8% |
| Phase 1/2 | 2 | 2 | 15.4% |
| Phase 2 | 2 | 0 | 15.4% |
| Phase 1 | 1 | 0 | 7.7% |
| Phase 2/3 | 1 | 1 | 7.7% |
Most active sponsors
| Lead sponsor | Studies | Recruiting |
|---|---|---|
| Merck Sharp & Dohme LLC | 5 | 4 |
| Eli Lilly and Company | 2 | 1 |
| BioNTech SE | 1 | 1 |
| Bristol-Myers Squibb | 1 | 1 |
| Eisai Inc. | 1 | 0 |
| Pfizer | 1 | 0 |
| Seagen, a wholly owned subsidiary of Pfizer | 1 | 0 |
| Stemline Therapeutics, Inc. | 1 | 1 |