A RT-qPCR Diagnostic System to Monitor Toca 511, a Cancer-selective Gene Therapy for the Treatment of Patients with Recurrent High-grade Glioma.

e13508Background: Toca 511 (vocimagene amiretrorepvec) is an investigational retroviral replicating vector that encodes the transgene cytosine deaminase. Toca 511 is delivered by multiple routes and selectively infects and spreads in tumor cells. Subsequent oral administration of investigational extended-release 5-fluorocytosine results in formation of the antineoplastic drug 5-fluorouracil within infected tumors, killing cancer and myeloid-derived suppressor cells. This results in durable and selective immune activity against cancer in preclinical models. As it is the first replicating retroviral therapy to enter a clinical trial, monitoring patients for potential nonspecific viremia is critical. This study determines if Toca 511 can be detected in multiple body fluids to support Toca 5, a Phase 2/3 clinical trial in patients with recurrent high-grade glioma (NCT01470794). Methods: Multiple lots of Toca 511 were spiked into a proprietary Tocagen Buffer (TB), SeraCon II basepool (BP; Siemens Healthcare-mo...