Encouraging Survival, Proof of Mechanism, and Favorable Safety Was Demonstrated

CHICAGO – May 3, 2016 – Tocagen Inc., a clinical-stage, cancer-selective gene therapy company, today announced positive clinical data involving intravenously delivered Toca 511 (vocimagene amiretrorepvec) in combination with Toca FC (extended-release flucytosine) for the treatment of recurrent high grade glioma were presented at the 84th American Association of Neurological Surgeons (AANS) Annual Scientific Meeting in Chicago.

The podium presentation was delivered by Steven N. Kalkanis, M.D., chair of the department of neurosurgery and co-director of the Neuroscience Institute at Henry Ford Hospital, on behalf of the clinical investigators participating in the trial.

Highlights of results are below. More information about the presentation, including abstract number and title, can be found on Tocagen’s website.

• Survival probability at 12 months was 61.3% and median survival was 13.6 months
• A complete radiologic response, based on independent radiology review was noted
• Combination of IV and intracranial Toca 511 was generally well tolerated
• Patients received up to 47 billion transduction units of Toca 511
• Resected tumor from 11 patients with recurrent high grade glioma treated with Toca 511 & Toca FC showed presence of viral DNA in a dose-dependent manner with 10/14 (71%) detectable overall of which 7/9 (78%) were in subjects treated with 3 day delivery
• Expression of yeast CD transgene was detectable by immunohistochemistry
• More information about the trial can be found at ClinicalTrials.gov using the identifier NCT01985256

“These encouraging data involving intravenously delivered Toca 511 support additional investigation in patients with primary brain cancer and metastatic cancers,” said Harry Gruber, M.D., CEO of Tocagen.

About Tocagen
Tocagen is a clinical-stage, cancer-selective gene therapy company focused on developing first-in-class, broadly applicable product candidates designed to activate a patient’s immune system against their own cancer from within. The company is developing its lead investigational product candidate, Toca 511 (vocimagene amiretrorepvec) & Toca FC (extended-release 5-fluorocytosine), initially for the treatment of recurrent high grade glioma (HGG), a disease with significant unmet medical need. Tocagen has initiated the Phase 2 portion of a randomized, controlled Phase 2/3 clinical trial of Toca 511 & Toca FC in patients with recurrent HGG, which is designed to serve as a potential registrational trial. More information about the clinical trial can be found at www.tocagen.com/toca5. In 2016, Tocagen plans to initiate clinical trials of Toca 511 & Toca FC in patients with newly diagnosed HGG and other solid tumors. Tocagen obtained Fast Track designation from the U.S. Food and Drug Administration, for Toca 511 & Toca FC for the treatment of recurrent HGG and Orphan drug designation for the treatment of glioblastoma (GBM), a subset of HGG. Tocagen has received grant support from leading brain cancer foundations, including Accelerate Brain Cancer Cure (ABC2), National Brain Tumor Society (NBTS), American Brain Tumor Association (ABTA), Musella Foundation and Voices Against Brain Cancer (VABC). For more information, visit www.tocagen.com or follow @Tocagen.