This is an open label neoadjuvant (treatment with VS-6063 prior to mesothelioma surgery) study in subjects with malignant pleural mesothelioma who are eligible for surgery. Subjects will receive VS-6063 (defactinib) 400 mg twice daily for 12, 21, or 35 days. Pre- and post-treatment biopsies and blood samples will be collected. The purpose of this study is to assess biomarker responses from tumor tissue. The safety, pharmacokinetics, and tumor response rate to VS-6063 (defactinib) will be also be assessed.