Study CTKI258A2202: A multicenter, open-label phase II trial of dovitinib (TKI258) in FGFR1-amplified and nonamplified HER2-negative metastatic breast cancer.

TPS122 Background: Dovitinib (TKI258) is an oral investigational drug that inhibits fibroblast growth factor (FGF), platelet-derived growth factor-β, and vascular endothelial growth factor (VEGF) receptor kinases with in vitro IC50 values of ∼10 nM. Dovitinib causes antitumor responses ranging from growth inhibition to regression in xenograft tumor models. Amplification of FGFR1 occurs in approximately 10% of breast tumors, and is an independent predictor of overall survival. FGFR1 amplification is uncommon in human epidermal growth factor receptor 2 (HER2) amplified BCs and is predominantly found in estrogen receptor (ER) positive, luminal type BCs. These data support testing dovitinib in women with HER2-negative (HER2-), FGFR1-amplified (FGFR1+) BC. In addition, the antiangiogenic activity of dovitinib may elicit antitumor activity in women with FGFR1-unamplified (FGFR1-) BC. Methods: This multicenter, open-label, 2-stage, phase II trial of dovitinib in FGFR1+ and FGFR1- metastatic HER2- breast cancer w...