ERC1 and breast cancer: Response occurred in dose levels 20–40 mg and were seen in FGFR2/3 fusion patients [5 patients (20%)] and included 1 patient with pancreatic cancer with FGFR2-SEPT7 fusion, 1 patient with breast cancer with FGFR2-ABLIM1 fusion plus an N549D mutation (molecular brake), 1 patient with cancer of unknown primary with FGFR2-ERC1 fusion, and 2 patients with gastroesophageal junction cancer with FGFR2 fusions.