TyTAN was a two-part, parallel-group, phase III study in Asian patients. An open-label, dose-optimization phase (n = 12) was followed by a randomized phase (n = 261), in which patients who were HER2 positive by fluorescence in situ hybridization (FISH) received lapatinib 1,500 mg once per day plus once-per-week paclitaxel 80 mg/m(2) or paclitaxel alone...ORR was higher with lapatinib plus paclitaxel versus paclitaxel alone (odds ratio, 3.85; P < .001). Better efficacy with lapatinib plus paclitaxel was demonstrated in IHC3+ compared with IHC0/1+ and 2+ patients and in Chinese compared with Japanese patients.

Tyverb is indicated for the treatment of patients with breast cancer, whose tumours overexpress HER2 (ErbB2):...in combination with an aromatase inhibitor for post-menopausal women with hormone-receptor-positive metastatic disease, not currently intended for chemotherapy.

...HER2-positive is defined as HER2 overexpression and/or amplification as determined by immunohistochemistry (3+) or fluorescence in situ hybridization (FISH) (>= 2.0)...