PTK2 and neoplasm: The failure of the phase 2 placebo-controlled study of defactinib (VS-6063) in subjects with MPM (COMMAND), taken together with our finding that FAK inhibition can interfere with MPM spheroid growth in vitro and tumor growth and angiogenesis in vivo, highlights the importance of exploring combination therapeutic options to fully exploit the anti-tumor activity of FAK inhibitors in this fatal malignancy.