Lapatinib: an Oral Dual Tyrosine Kinase Inhibitor for HER-2-positive Breast Cancer

Breast cancer is the most common form of cancer and the second leading cause of cancer deaths among women in the USA. A quarter of all newly diagnosed cases are characterized by overexpression of HER-2 which is associated with poor prognosis. In March 2007, lapatinib, an oral dual-tyrosine kinase inhibitor was approved in combination with capecitabine for metastatic HER-2-positive breast cancer that has progressed on prior trastuzumab therapy, and in combination with letrozole for postmenopausal women with HER-2 and hormone receptor-positive advanced breast cancer. In the future, lapatinib may play an important role in dual HER-2 blockade with trastuzumab and other targeted agents for women with HER-2-overexpressing breast cancer.