Given the improvement observed with trastuzumab emtansine (KADCYLA) in monotherapy compared to the combination of lapatinib (TYVERB) + capecitabine (XELODA) in terms of progression-free survival and overall survival and an acceptable safety profile, the Transparency Committee believes that KADCYLA, as a monotherapy, provides a substantial improvement in actual benefit (IAB II) in the treatment of adult patients with HER2 positive metastatic or locally advanced unresectable breast cancer, who were previously treated with trastuzumab and a taxane, separately or in combination.