The oral kinase inhibitor tucatinib (Tukysa – Seagen) has received accelerated approval from the FDA for use in combination with trastuzumab (Herceptin) for treatment of adults with RAS wild-type human epidermal growth factor receptor 2 (HER2)-positive unresectable or metastatic colorectal cancer that has progressed following treatment with fluoropyrimidine-, oxaliplatin-, and irinotecan-based chemotherapy regimens. Tucatinib was approved in 2020 for use in combination with trastuzumab and capecitabine (Xeloda, and generics) for treatment of adults with advanced unresectable or metastatic HER2-positive breast cancer, including those with brain metastases, who received at least one prior anti-HER2-based regimen for metastatic disease.

The FDA has approved two new drugs for treatment of previously-treated unresectable or metastatic human epidermal growth factor receptor 2 (HER2)-positive breast cancer: fam-trastuzumab deruxtecannxki (Enhertu – Daiichi-Sankyo/AstraZeneca), an IV HER2-directed monoclonal antibody linked to the topoisomerase I inhibitor DXd, and tucatinib (Tukysa – Seagen), an oral tyrosine kinase inhibitor.