Pilot trial of vigil immunotherapy in Ewing’s sarcoma.

10522 Background: Ewing’s sarcoma is the second most common primary bone malignancy in children and adolescents. While front-line intensive multimodality treatment significantly improves survival in first line treatment, the prognosis for metastatic patients with either disease relapse within two years of initial therapy or initially resistant to chemotherapy is very poor with few long-term survivors and 1-year survival generally less than 20%. Methods: We implemented a Phase I trial of 12 metastatic Ewing’s sarcoma patients who were either multiply recurrent (n = 11) or had failed frontline treatment within 2 years (n = 1). Patients received Vigil (previously called FANG) vaccine dosed between 1x106, 4x106, 1x107 or 2.5x107cells/intradermal injection/month for ≥ 4 months. Vigil is comprised of irradiated autologous tumor transfected with a dual DNA plasmid expressive of GMCSF and bi-shRNA furin components. Knockdown of furin down regulates both downstream TGFβ1 and TGFβ2 expression. Safety and clinical r...