Fibroblast kinase 1-3 inhibitor BGJ398 in patients with FGFR1 amplified squamous non-small cell lung cancer treated in a phase I study: Evaluation of tumor tissue and response at a single center.

e20664Background: Fibroblast growth factor receptor 1 (FGFR1) amplification in squamous cell non-small cell lung cancer (sqNSCLC) has been described as potential oncogenic and targetable driver in cell lines and murine models. However, a phase I study evaluating FGFR 1-3 inhibitor BGJ398 showed moderate response rate of 11% in FGFR1amplified sgNSCLC treated with dose ≥ 100mg. To identify underlying mechanisms of resistance, we analyzed tumor tissues of selected patients. Methods: Within the phase I BGJ398 study, patients (pts) with FGFR1amplified sqNSCLC were treated orally with escalating dose (5 to 150mg) of BGJ398 once daily (QD) or 50mg twice a day. In the expansion phase, pts received BGJ398 either continuously QD or on a 3-weeks on/1-week off schedule. CT scans for response were performed every 8 weeks. Available tumor tissue of pts treated with BGJ398 at our center was analyzed using hybrid capture–based massively parallel sequencing (CAGE). Results: Twenty-one pts with FGFR1 amplified sqNSCLC were...