FPA144-001: A first in human study of FPA 144, an ADCC-enhanced, FGFR2b isoform-selective monoclonal antibody in patients with advanced solid tumors.

140 Background: FPA144 is a humanized monoclonal IgG1 antibody directed against the 2b Isoform of thefibroblast growth factor receptor (FGFR2b) that has been glycoengineered to enhance ADCC. Amplification of FGFR2 is found in a number of tumors, including 3 – 9% of gastric cancer, and is associated with poor prognosis. FPA144-001 is a phase 1 study in two parts: Part 1 will evaluate the safety and pharmacokinetics (PK) of FPA144 in patients with solid tumors; Part 2 will evaluate efficacy in gastric cancer patients whose tumors overexpress FGFR2b, as determined by a proprietary test. Here we present early safety and PK results from solid tumor patients treated with FPA144. Methods: A standard 3+3 design was used to assess safety, tolerability and PK of escalating doses of FPA144 in patients with advanced solid tumors (Part 1A) or recurrent/metastatic gastric cancer (Part 1B). Tumor testing for FGFR2gene amplification or FGFR2b overexpression was conducted centrally by a proprietary assay consisting of bot...