FDA approves palbociclib with trastuzumab, with or without pertuzumab, and endocrine therapy for the maintenance treatment of HR-positive, HER2-positive metastatic breast cancer
Regulatory approval: On June 24, 2026, the FDA approved palbociclib (Ibrance) in combination with trastuzumab, with or without pertuzumab, and endocrine therapy for maintenance treatment of adults with HR-positive, HER2-positive locally advanced or metastatic breast cancer following induction therapy. The decision was supported by the randomized, open-label PATINA trial, which showed a statistically significant improvement in investigator-assessed PFS versus trastuzumab-based maintenance plus endocrine therapy alone; OS data were not mature.
FDA approval (June 24, 2026)
The US Food and Drug Administration (FDA) approved palbociclib (Ibrance; Pfizer) with trastuzumab, with or without pertuzumab, plus endocrine therapy for the maintenance treatment of adults with HR-positive, HER2-positive locally advanced or metastatic breast cancer following induction treatment.
Supporting evidence: PATINA (NCT02947685)
Efficacy was evaluated in PATINA, a randomized, open-label trial (n=518) enrolling patients with HR-positive, HER2-positive locally advanced or metastatic breast cancer with no evidence of progression after induction with a taxane + trastuzumab, with or without pertuzumab.
Patients were randomized 1:1 to:
- Palbociclib + trastuzumab (± pertuzumab) + endocrine therapy (fulvestrant or an aromatase inhibitor: anastrozole, letrozole, or exemestane), or
- Trastuzumab (± pertuzumab) + endocrine therapy alone.
The major endpoint was investigator-assessed PFS per RECIST v1.1. The palbociclib-containing regimen improved PFS (HR 0.76, 95% CI 0.59–0.97; 1-sided p=0.0134). Median PFS could not be adequately described due to censoring. OS data were not mature at the time of PFS analysis.
Safety and dosing highlights
Label warnings/precautions include neutropenia, interstitial lung disease/pneumonitis, and embryo-fetal toxicity. Recommended palbociclib dose: 125 mg orally once daily for 21 days on/7 days off (28-day cycles).