A Study of H3B-6545 in Combination With Palbociclib in Women With Advanced or Metastatic Estrogen Receptor-Positive Human Epidermal Growth Factor Receptor-2 (HER2)-Negative Breast Cancer
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Phase
Phase 1
Status
Active, not recruiting
Study type
Interventional
Design
Na · None · Treatment
Enrollment
31actual
Sites
8
Countries
United Kingdom, United States
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 | 2020-04-01 | actual | When the study began enrolling |
| Primary completion | 2022-09-16 | actual | The date the last participant is measured for the primary outcome — the readout window |
| Study completion | 2027-03-31 | estimated | The whole study's end, after follow-up |
| First posted | 2020-02-27 | actual | When this record first appeared on the registry |
| Results posted | 2024-03-22 | actual | When the sponsor posted results to the registry |
| Record updated | 2026-02-27 | actual | The sponsor's own last edit to this record — every projection above is as current as this date |
What it studies
Conditions
- Receptors, Estrogen
- Genes, Erbb-2
- Breast Neoplasms
Interventions
- Drug: Palbociclib (75, 100, 125 milligram [mg])
- Drug: H3B-6545 (150, 300, 450 mg)
Primary outcome
what the primary-completion date above is the date OFMaximum Tolerated Dose (MTD) of H3B-6545 and Palbociclib
measured Cycle 1 (Cycle length = 28 Days)
Posted documents
hosted by the registry — we link, never re-serveStudy Protocolposted 2022-08-29 · 915 KB · Prot_000.pdf
Statistical Analysis Planposted 2022-11-10 · 557 KB · SAP_001.pdf
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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