A Study of Tucatinib or Placebo With Trastuzumab and Pertuzumab for Metastatic HER2+ Breast Cancer
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Phase
Phase 3
Status
Active, not recruiting
Study type
Interventional
Design
Randomized · Quadruple · Treatment
Enrollment
654actual
Sites
307
Countries
Australia, Austria, Belgium +20
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 | 2022-03-07 | actual | When the study began enrolling |
| Primary completion | 2025-09-05 | actual | The date the last participant is measured for the primary outcome — the readout window |
| Study completion | 2027-09-28 | estimated | The whole study's end, after follow-up |
| First posted | 2021-11-24 | actual | When this record first appeared on the registry |
| Results posted | — | When the sponsor posted results to the registry | |
| Record updated | 2026-07-22 | actual | The sponsor's own last edit to this record — every projection above is as current as this date |
What it studies
Condition
- HER2 Positive Breast Cancer
Interventions
- Drug: Tucatinib — also filed as TUKYSA, ONT-380, ARRY-380
- Drug: Trastuzumab — also filed as Herceptin, Herceptin Hylecta
- Drug: Pertuzumab — also filed as Perjeta
- Drug: Combination product: Trastuzumab + Pertuzumab — also filed as Phesgo
- Drug: Placebo
Primary outcome
what the primary-completion date above is the date OFProgression-free survival (PFS) by investigator assessment per Response Evaluation Criteria in Solid Tumors (RECIST) v1.1
measured Up to approximately 3 years
Publications
- PMID 41369677 — 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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