Study of a Retroviral Replicating Vector Combined With a Prodrug to Treat Patients Undergoing Surgery for a Recurrent Malignant Brain Tumor

All patients will receive Toca 511, a retroviral replicating vector that expresses the cytosine deaminase (CD) gene. CD converts the antifungal 5-FC to the anti-cancer drug 5-FU in cells that have been infected by the Toca 511 vector. Beginning approximately 6 weeks after administration of Toca 511, patients will begin courses of oral Toca FC at pre-specified intervals, depending on cohort, during the approximately 30 week study.