Definition

A drug used with other drugs to treat adults with certain types of HER2-positive breast cancer or certain types of HER2-positive colorectal cancer that do not have a mutation (change) in the RAS gene. It is also being studied in the treatment of other types of cancer. Tucatinib blocks a protein called HER2, which may help keep cancer cells from growing and may kill them. It is a type of tyrosine kinase inhibitor. Also called Tukysa.