FINESSE: An open, three-cohort, phase II trial testing oral administration of lucitanib in patients with FGFR1-amplified or nonamplified estrogen receptor-positive metastatic breast cancer.

TPS1134 Background: FGF aberrancy is observed in approximately 25% of breast cancer (BC) patients. Preclinical studies demonstrated that targeting FGFR could lead to antitumor effects. Lucitanib is a multikinase inhibitor targeting FGFR1-2, VEGFR1-3 and PDGFRA/B. In the phase I trial testing lucitanib continuous dosing, 6 objective responses were observed in 12 evaluable patients presenting with FGFR1 and/or FGF3-4-19 (11q) amplification. Based on this, a phase II trial has been initiated. Methods: This is a phase II trial testing the efficacy of lucitanib 15 mg daily in patients with ER+/HER2- metastatic BC who have received at least first line endocrine therapy in the metastatic setting. After informed consent, a biopsy of metastatic site is required to assess the presence of FGFR1- and/or 11q- amplification, which will be centrally evaluated using FISH. Testing could be also performed on archived metastatic biopsies. The primary objective is to evaluate the ORR of single agent lucitanib in metastatic B...