IBRANCE (palbociclib) in combination with trastuzumab, with or without pertuzumab - (PATINA)

June 24, 2026: Pfizer Inc. (NYSE: PFE) announced FDA approval of IBRANCE (palbociclib) in combination with trastuzumab, with or without pertuzumab, plus endocrine therapy as maintenance treatment for adults with HR-positive, HER2-positive locally advanced or metastatic breast cancer following induction treatment. The approval is based on the AFT-sponsored Phase 3 PATINA (AFT-38) trial.

In PATINA, adding IBRANCE to anti-HER2 therapy and endocrine therapy reduced the risk of progression or death versus anti-HER2 plus endocrine therapy alone (HR 0.76; 95% CI 0.59–0.97; one-sided p=0.0134), described as a 24% risk reduction. The study randomized patients after a median of six induction cycles (IBRANCE arm n=261; control n=257); the primary endpoint was investigator-assessed PFS. Overall survival is a secondary endpoint and is not yet mature.

Safety in PATINA was consistent with known IBRANCE safety; neutropenia was most frequent (78% any-grade; Grade ≥3 61%), with non-hematologic AEs including diarrhea, infections, stomatitis, and fatigue. Results were previously published in the New England Journal of Medicine and presented at the 2024 San Antonio Breast Cancer Symposium.