FDA approves tucatinib with trastuzumab and pertuzumab for the maintenance treatment of HER2-positive breast cancer
The FDA approved tucatinib (Tukysa, Seagen, a Pfizer subsidiary) with trastuzumab and pertuzumab on October 7, 2026, for maintenance treatment of adults with unresectable locally advanced or metastatic HER2-positive breast cancer after induction therapy. In the 654-patient HER2CLIMB-05 trial, median progression-free survival was 24.9 months with tucatinib 300 mg twice daily versus 16.3 months with placebo (HR 0.64, p<0.0001). The label carries a boxed warning for hepatotoxicity; overall survival data were immature.
Why it matters: FDA approval extends tucatinib to first-line maintenance, with PFS results from a randomized phase 3 trial.