FDA Approves Palbociclib Maintenance for Advanced Breast Cancer

The FDA approved palbociclib (Ibrance, Pfizer) 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 treatment.

The approval was supported by PATINA, a randomized, open-label trial involving 518 patients whose disease had not progressed after induction treatment with a taxane and trastuzumab, with or without pertuzumab, for advanced disease. Participants were randomly assigned 1:1 to receive palbociclib plus trastuzumab, with or without pertuzumab, and endocrine therapy or the same regimen without palbociclib. Endocrine therapy consisted of fulvestrant or an aromatase inhibitor—anastrozole, letrozole, or exemestane.

The primary efficacy outcome was investigator-assessed progression-free survival (PFS) under Response Evaluation Criteria in Solid Tumors version 1.1. Adding palbociclib produced a statistically significant improvement in PFS compared with trastuzumab, with or without pertuzumab, and endocrine therapy alone (hazard ratio, 0.76; 95% CI, 0.59-0.97; 1-sided P=0.0134). Median PFS could not be adequately described because of censoring. Overall survival was an additional efficacy outcome, but the data were not mature at the time of the PFS analysis.

The palbociclib prescribing information includes warnings and precautions for neutropenia, interstitial lung disease/pneumonitis, and embryo-fetal toxicity. The recommended dose is 125mg orally once daily for 21 consecutive days, followed by 7 days without treatment, in each 28-day cycle. Treatment in PATINA continued until disease progression or unacceptable toxicity.

Palbociclib received FDA Breakthrough Therapy designation, and the review used the agency’s Assessment Aid. The approval applies to the specified maintenance setting after induction treatment; overall survival data remained immature at the PFS analysis.

Source:US Food and Drug Administration. FDA approves palbociclib with trastuzumab, with or without pertuzumab, and endocrine therapy for the maintenance treatment of HR-positive, HER2-positive metastatic breast cancer. June 24, 2026. Accessed September 4, 2026.