K Jhaveri, L D Eli, H Wildiers, S A Hurvitz, A Guerrero-Zotano, N Unni, A Brufsky, H Park, J Waisman, E S Yang, I Spanggaard, S Reid, M E Burkard, S Vinayak, A Prat, M Arnedos, F-C Bidard, S Loi, J Crown, M Bhave, S A Piha-Paul, J M Suga, S Chia, C Saura, J Á Garcia-Saenz, V Gambardella, M J de Miguel, E N Gal-Yam, A Rapael, S M Stemmer, C Ma, A B Hanker, D Ye, J W Goldman, R Bose, L Peterson, J S K Bell, A Frazier, D DiPrimeo, A Wong, C L Arteaga, D B Solit
BACKGROUND: HER2 mutations are targetable alterations in patients with hormone-receptor positive (HR+) metastatic breast cancer (MBC). In the SUMMIT basket study, patients with HER2-mutant MBC received neratinib monotherapy, neratinib+fulvestrant, or neratinib+fulvestrant+trastuzumab (N+F+T). We report results from 71 patients with HR+, HER2-mutant MBC, including 21 (7 in each arm) from a randomized substudy of fulvestrant versus fulvestrant+trastuzumab (F+T) versus N+F+T. PATIENTS AND METHODS: Patients with HR+ HER2-negative MBC with activating HER2 mutation(s) and prior CDK4/6 inhibitor therapy received N+F+T (oral neratinib 240 mg/d with loperamide prophylaxis, intramuscular fulvestrant 500 mg days 1, 15, 29 of cycle 1 then q4w, intravenous trastuzumab 8 mg/kg then 6 mg/kg q3w) or F+T or fulvestrant alone...
August 17, 2023: Annals of Oncology: Official Journal of the European Society for Medical Oncology