FDA approves palbociclib with trastuzumab, with or without pertuzumab, and endocrine therapy for the maintenance treatment of HR-positive, HER2-positive metastatic breast cancer

On June 24, 2026, the Food and Drug Administration approved palbociclib (Ibrance, Pfizer Inc.) in combination with trastuzumab, with or without pertuzumab, and endocrine therapy for the maintenance treatment of adults with HR-positive, HER2-positive locally advanced or metastatic breast cancer following induction treatment.

Full prescribing information for Ibrance will be posted on Drugs@FDA.

Efficacy and Safety

Efficacy was evaluated in PATINA (NCT02947685), a randomized, open-label trial in 518 patients with HR-positive, HER2-positive locally advanced or metastatic breast cancer who had no evidence of disease progression after induction treatment with a taxane and trastuzumab, with or without pertuzumab, for their advanced disease. Patients were randomized (1:1) to receive either palbociclib with trastuzumab, with or without pertuzumab, and endocrine therapy (fulvestrant or an aromatase inhibitor [anastrozole, letrozole, or exemestane]) or trastuzumab, with or without pertuzumab, and endocrine therapy alone. Patients received treatment until disease progression or unacceptable toxicity.

The major efficacy outcome measure was investigator-assessed progression-free survival (PFS) per RECIST version 1.1. Overall survival (OS) was an additional efficacy outcome measure. A statistically significant improvement in investigator-assessed PFS was observed for palbociclib with trastuzumab, with or without pertuzumab, and endocrine therapy compared to trastuzumab, with or without pertuzumab, and endocrine therapy alone (Hazard ratio 0.76 [95% CI: 0.59, 0.97], 1-sided p-value 0.0134). Median PFS could not be adequately described because of censoring. At the time of the PFS analysis, OS data were not mature.

The palbociclib prescribing information includes warnings and precautions for neutropenia, interstitial lung disease/pneumonitis, and embryo-fetal toxicity.

Recommended Dosage

The recommended palbociclib dosage is 125 mg orally once daily for 21 consecutive days, followed by seven days off treatment to comprise a complete cycle of 28 days. Refer to the prescribing information for the recommended dosages for trastuzumab, pertuzumab, and endocrine therapy.

This review used the Assessment Aid, a voluntary submission from the applicant to facilitate the FDA’s assessment.

Palbociclib received breakthrough therapy designation. A description of FDA expedited programs is in the Guidance for Industry: Expedited Programs for Serious Conditions-Drugs and Biologics.

Healthcare professionals should report all serious adverse events suspected to be associated with the use of any medicine and device to FDA’s MedWatch Reporting System or by calling 1-800-FDA-1088.

For assistance with single-patient INDs for investigational oncology products, healthcare professionals may contact OCE’s Project Facilitate at 240-402-0004 or email OncProjectFacilitate@fda.hhs.gov.

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