A Study of BB-1701 in Previously Treated Participants With Human Epidermal Growth Factor Receptor 2 (HER2)-Positive or HER2-low Unresectable or Metastatic Breast Cancer
← catalyst calendarSponsored by Eisai Inc. (industry) · 4523.T — their whole pipeline →. With Bliss Biopharmaceutical (Hangzhou) Co., Ltd.
Phase
Phase 2
Status
Completed
Study type
Interventional
Design
Randomized · None · Treatment
Enrollment
56actual
Sites
49
Countries
France, Japan, Spain +1
Every value on this page is a field the sponsor filed with ClinicalTrials.gov, reproduced. Dates are their own estimates, revised as a study runs, unless the registry marks them actual. sources →
Source: ClinicalTrials.gov, retrieved 2026-08-19
Dates
each axis at the precision it was filed, with the registry's own basis| Date | Filed | Basis | What it is |
|---|---|---|---|
| Start | 2024-04-10 | actual | When the study began enrolling |
| Primary completion | 2026-03-18 | actual | The date the last participant is measured for the primary outcome — the readout window |
| Study completion | 2026-03-18 | actual | The whole study's end, after follow-up |
| First posted | 2024-01-03 | actual | When this record first appeared on the registry |
| Results posted | — | When the sponsor posted results to the registry | |
| Record updated | 2026-05-22 | actual | The sponsor's own last edit to this record — every projection above is as current as this date |
What it studies
Condition
- Breast Cancer
Intervention
- Drug: BB-1701
Primary outcomes
what the primary-completion date above is the date OFPart 1, Dose Optimization: Number of Participants With Adverse Events (AEs)
measured Baseline up to 35 months
Part 1, Dose Optimization: Number of Participants With Clinically Significant Laboratory Values
measured Baseline up to 35 months
Part 1, Dose Optimization: Number of Participants With Clinically Significant Vital Sign Values
measured Baseline up to 35 months
Part 1, Dose Optimization: Number of Participants With Clinically Significant 12-lead ECGs Values
measured Baseline up to 35 months
Part 1, Dose Optimization: Number of Participants With Eastern Cooperative Oncology Group (ECOG) Performance Status (PS)
measured Baseline up to 35 months
Part 1, Dose Optimization: Objective Response Rate (ORR)
measured From date of first dose of study drug until first documentation of CR or PR (up to 35 months)
Part 2, Dose Expansion: Objective Response Rate (ORR) Based on Blinded Independent Central Review (BICR) Assessment per RECIST v1.1
measured From date of first dose of study drug until first documentation of CR or PR (up to 35 months)
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