TPS8120 Background: FP1039/GSK3052230 (GSK230) is a soluble fusion protein that acts as a ligand trap by sequestering fibroblast growth factors (FGFs) involved in tumor growth. FGF ligand-dependent signaling plays an important role in cancer development and growth through autocrine production of FGFs from cancer cells, or paracrine production of FGFs from local stroma, or by tumor overexpression of FGF receptors (FGFRs) or amplification of FGFR genes. FGFR1 amplification has been identified in ~15-20% of squamous non-small cell lung cancers (NSCLC) and is associated with shorter disease-free and overall survival. Efficacy was observed with GSK230 + chemotherapy in FGFR1 amplified in NSCLC xenograft models and in xenograft models of malignant pleural mesothelioma (MPM) where FGF2 mRNA levels were overexpressed. In a phase I study, no maximum tolerated dose (MTD) was identified and 20 mg/kg weekly was the maximum feasible dose (MFD) achieving the desired target concentration. Toxicities associated with smal...