PXD101 is an orally administered histone deacetylase inhibitor that is being used as a second line therapy in treating patients with mesothelioma that cannot be removed with surgery. It is an anti-angiogenesis drug treatment that is being used in clinical trials across the United Stated including the Yale Cancer Medical Center. Heading the research into this drug at Yale is Dr. Scott Gettinger, a medical oncologist in the Thoracic Oncology Program (TOP) at Yale who has gotten PXD101 into Phase 1 of FDA clinical trials. Although not the same for every patient the most common side effects of PXD101 include being tired and/or fatigued, along with low-grade nausea, which can be treated with medications. These side effects have proven to be minimal and less severe than the effects of chemotherapy or radiation.