Galinpepimut-S (WT-1 Analog Peptide) Vaccine in Malignant Pleural Mesothelioma After Combined Modality Therapy

Inclusion Criteria: * Pathologic diagnosis of malignant pleural mesothelioma (MPM) confirmed at participating institution. * Positive immunohistochemical staining for WT-1 (greater than 10% of cells). * Completion of multimodality therapy. This must include surgical resection by either pleurectomy/decortication or extrapleural pneumonectomy. The surgery should be performed with the intent of complete resection, though patients with an R1 resection will still be eligible. Patients should have also received treatment with chemotherapy and/or radiation. Patients with an R2 resection are also eligible as long as the site of residual disease is treated post-operatively with radiotherapy. * 4-12 weeks since completion of combined modality therapy. * Age \> or = to 18 years * Karnofsky performance status \> or = to 70% * Hematologic parameters: Absolute neutrophil count \> or = to 1000/mcL, Platelets \> or = to 50K/mcL. * Biochemical parameters: Total bilirubin \< or = to 2.0 mg/dl, AST and ALT \< or = to 2.5 x upper limits of normal, Creatinine \< or = to 2.0 mg/dl. Exclusion Criteria: * Pregnant or lactating women. * Patients with active infection requiring systemic antibiotics, antiviral, or antifungal treatments. * Patients with a serious unstable medical illness or another active cancer. * Patients taking systemic corticosteroids. * Patients with an immunodeficiency syndrome.