Study of H3B-6545 in Japanese Women With Estrogen Receptor (ER)-Positive, Human Epidermal Growth Factor Receptor 2 (HER2)-Negative Breast Cancer
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Phase
Phase 1
Status
Completed
Study type
Interventional
Design
Randomized · None · Treatment
Enrollment
33actual
Sites
2
Country
Japan
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 | 2020-09-30 | actual | When the study began enrolling |
| Primary completion | 2025-10-01 | actual | The date the last participant is measured for the primary outcome — the readout window |
| Study completion | 2025-10-01 | actual | The whole study's end, after follow-up |
| First posted | 2020-09-29 | actual | When this record first appeared on the registry |
| Results posted | — | When the sponsor posted results to the registry | |
| Record updated | 2025-10-23 | actual | The sponsor's own last edit to this record — every projection above is as current as this date |
What it studies
Condition
- Breast Neoplasms
Interventions
- Drug: H3B-6545
- Drug: Antihistamine
Primary outcomes
what the primary-completion date above is the date OFNumber of Participants With Dose-limiting Toxicities (DLTs)
measured Up to Cycle 1 (each cycle length is equal to [=] 28 days)
Number of Participants With Treatment Emergent Adverse Events (TEAEs) and Serious Adverse Events (SAEs)
measured Baseline up to 36 months
Percentage of Participants With Incidence of Rash
measured Baseline up to 36 months
Number of Participants With Clinically Significant Change From Baseline in Laboratory Values
measured Baseline up to 36 months
Number of Participants With Clinically Significant Change From Baseline in Vital Sign Values
measured Baseline up to 36 months
Number of Participants With Clinically Significant Change From Baseline in Weight Values
measured Baseline up to 36 months
Number of Participants With Clinically Significant Change From Baseline in 12-lead Electrocardiogram (ECG) Findings
measured Baseline up to 36 months
Number of Participants With Clinically Significant Change From Baseline in Physical Examinations
measured Baseline up to 36 months
Number of Participants With Clinically Significant Change From Baseline in Eastern Cooperative Oncology Group Performance Status (ECOG-PS)
measured Baseline up to 36 months
Publications
- PMID 35642432 — linked by the registry
Linked on the registry record. A “linked by the registry” entry is NLM's own automated PubMed match, not a claim by the sponsor that the paper reports this study.
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