On Mar. 9, 2018, Seattle Genetics announced it had completed its acquisition of Cascadian Therapeutics for approximately $614 million.

The most advanced program in Cascadian Therapeuticsﾒ pipeline was tucatinib, an investigational oral tyrosine kinase inhibitor (TKI) that is highly selective for HER2, a growth factor receptor that is overexpressed in multiple cancers, including breast, colorectal, ovarian and gastric. Tucatinib is currently being evaluated in a randomized global pivotal trial called HER2CLIMB for patients with HER2-positive (HER2+) metastatic breast cancer, including patients with or without brain metastases.