This is a multicenter, randomized, open-label study of Toca 511 and Toca FC versus standard of care (SOC) that comprises Investigators choice of either single agent chemotherapy (lomustine or temozolomide) or bevacizumab administered to subjects undergoing resection for first or second recurrence (including this recurrence) of glioblastoma or anaplastic astrocytoma. Subjects will be randomized at the time of surgery in a 1:1 ratio to receive either Toca 511 and Toca FC or control. Stratification will be done by IDH mutation (present or absent), by Karnofsky performance status (KPS [70-80 vs 90-100]) and by geographical region. All subjects will have a Gd-MRI scan 24 to 48 hours after the resection for recurrent disease and a baseline scan prior to initiating Toca FC, chemotherapy, or bevacizumab. Repeat scans will be obtained every 6 weeks for the first year and every 3 months after that. Subjects may receive any standard of care treatment following progression or discontinuation from study due to toxicity. Crossover to the Experimental arm is not allowed, unless the primary endpoint is met and the Sponsor notifies the sites. An Independent Data Monitoring Committee (IDMC) will be convened to review safety data on a periodic basis. An efficacy analysis is planned to be conducted when 108 events (deaths) have occurred in the Phase 2 portion of the study. Enrollment into the Phase 3 portion of the study will not commence until topline results from the Phase 2 portion of the study are available.

You may be eligible for this study if you meet the following criteria:

• Conditions: Astrocytoma, Brain Neoplasms, Glioblastoma
• Age: 18 years - 75 years
• Gender: All