Tocagen's First-in-Human Clinical Trial of Toca 511 Enrolling Patients with High Grade Glioma

SAN DIEGO, June 7, 2011 /PRNewswire/ -- Tocagen Inc. today announced the company is enrolling patients with recurrent high grade glioma, such as those with glioblastoma multiforme (GBM, Grade 4), in its first-in-human clinical trial of Toca 511.

The multicenter, open-label study is evaluating the safety and tolerability of single ascending doses of Toca 511 administered intratumorally followed by cycles of the prodrug 5-fluorocytosine (5-FC) in patients who have failed prior surgery and chemoradiation. Patients will receive a single dose of Toca 511, a gene transfer viral vector that delivers a cytosine deaminase (CD) gene to tumor cells. After the vector is allowed to spread through the tumor for approximately 4 weeks, patients receive a six-day course of oral 5-FC. In the tumor cells expressing the CD gene, 5-FC is converted by the CD enzyme into the anti-cancer drug 5-fluorouracil (5-FU). Subsequently, patients receive additional cycles of oral 5-FC monthly for up to six months.

"There are limited treatment options available for patients with glioblastoma. It is therefore a priority to explore potential new therapies to treat this form of cancer," said Timothy Cloughesy, M.D., Director of the Neuro-Oncology Program at the University California, Los Angeles Jonsson Cancer Center and a principal investigator for the Toca 511 study. "Toca 511 is a novel approach that offers new hope to combating this deadly disease."

In studies performed in animal models of GBM, nearly all animals treated with Toca 511 followed by 5-FC lived for the duration of the study (six months), compared to less than two months for control (untreated) animals. Toca 511 spread through the brain tumors and, following 5-FC treatment, marked tumor regression occurred while healthy brain tissue was unharmed.

"Unlike conventional cancer treatments in which toxic side effects limit how much drug can be given, Toca 511 has the potential to deliver cancer-killing drug to tumors without systemic side effects," said Harry E. Gruber, M.D., chief executive officer of Tocagen.  "We plan to present the clinical data from this study at a scientific conference focused on brain cancer."

About Tocagen

Tocagen Inc. is a privately funded, clinical stage biopharmaceutical company pursuing the discovery, development and commercialization of gene transfer products for the treatment of cancer. Tocagen is initially focusing on treatments for patients with advanced cancer for whom no adequate treatments currently exist. Toca 511, the company's lead investigational product candidate, is being evaluated in a Phase I/II clinical trial in patients with recurrent high grade glioma (such as glioblastoma multiforme). Tocagen has received grant support from leading brain cancer foundations including, Accelerate Brain Cancer Cure (ABC2), the American Brain Tumor Association (ABTA), and the National Brain Tumor Society (NBTS). For more information about Tocagen or Toca 511 please visit www.tocagen.com.

SOURCE Tocagen Inc.