HER2CLIMB-05
In HER2CLIMB-05, adding the brain-penetrant pill tucatinib to maintenance antibodies after first-line chemotherapy delayed progression by more than eight months.
SABCS 2025: PFS 24.9 vs 16.3 months (HR 0.64, P<0.0001), consistent across brain-metastasis and hormone-receptor subgroups. Offers a chemotherapy-free maintenance intensification; its place versus first-line T-DXd + pertuzumab (DESTINY-Breast09) is unsettled.
- Median 24.9 vs 16.3 months with Tucatinib + trastuzumab + pertuzumab compared with Placebo + trastuzumab + pertuzumab; about 8.6 months longer for half the group.
- A median is a midpoint: half the people did better than this and half did worse, so it is not a prediction for any one person.
- Put another way, the treated group had about 36 percent lower chance of the event at any given time (hazard ratio 0.641).
- The p-value (<0.0001) says a difference this large would rarely happen by chance; it does not say how large or how useful the difference is.
- This is a surrogate endpoint: it measures the cancer being controlled or absent on scans and tests, which often, but not always, translates into living longer.
- These results apply to the people the trial enrolled: First-line HER2+ metastatic breast cancer after induction with taxane + trastuzumab + pertuzumab: maintenance tucatinib + HP vs placebo + HP. People in a different situation may not see the same effect.
- The trial selected people by a biomarker (HER2); the result should not be assumed for people whose cancer does not have it.
Numbers are from the trial as recorded here; see the source links in the table below. This is orientation, not medical advice: ask your team how closely the trial population matches you.
654 participants enrolled.
| Endpoint | Arm | n | Value | HR (95% CI) | p | Source |
|---|---|---|---|---|---|---|
| Progression-free survivalprimary | Tucatinib + trastuzumab + pertuzumab | — | 24.9 months | 0.641 | <0.0001 | link |
| Placebo + trastuzumab + pertuzumab | — | 16.3 months |
Pages like this
not linked directly; found by shared links- PairingTucatinib + trastuzumab + capecitabine for brain metastases
Shares Tucatinib, Trastuzumab, HER2-positive breast cancer.
- TrialHER2CLIMB-02
Shares Tucatinib, HER2-positive breast cancer.
- PairingEarly FDG-PET response → chemotherapy omission (HER2+)
Shares Pertuzumab, Trastuzumab, HER2-positive breast cancer.
- TermTrastuzumab cardiotoxicity
Shares Pertuzumab, Trastuzumab, HER2-positive breast cancer.
- TrialAPHINITY
Shares Pertuzumab, Trastuzumab, HER2-positive breast cancer.
- TrialCLEOPATRA
Shares Pertuzumab, Trastuzumab, HER2-positive breast cancer.
- InstitutionGeorgetown Lombardi Comprehensive Cancer Center
Shares Pertuzumab, Trastuzumab, HER2-positive breast cancer.
- TrialPHERGain
Shares Pertuzumab, Trastuzumab, HER2-positive breast cancer.