A related commentary discussed the implications of this research, as well as another open label trial investigating trastuzumab emtansine vs capecitabine plus lapatinib (EMILIA study). It suggests that the final overall survival analysis of EMILIA lends further support to the early positioning of trastuzumab emtansine in the therapeutic sequence in patients with HER2-positive metastatic breast cancer, despite the results of TH3RESA showing that trastuzumab emtansine also extends survival when administered as later treatment lines. The more than 900 deaths reported in EMILIA and TH3RESA still remind us that, despite notable median overall survival prolongation, HER2-positive metastatic breast cancer remains a fatal disease in most patients, fully justifying the formidable ongoing research in this field.
NICE TA371 does not recommend trastuzumab emtansine for treating HER2-positive, unresectable locally advanced or metastatic breast cancer after treatment with trastuzumab and a taxane