New Immunotherapy Increases Survival Time for Patients With Brain Cancer

Tocagen, a cancer-selective gene therapy company, is developing a new immunotherapy for patients with recurrent brain cancer called Toca 511 and Toca FC, referred to as the “Toca regimen.” The investigational products are currently being evaluated in a phase 2/3 randomized, multicenter, open-label trial.

The trial is being conducted at 68 sites across the United States, Canada, Israel, and South Korea in patients undergoing planned resection for recurrent glioblastoma or anaplastic astrocytoma. Enrollment is scheduled to be completed by the end of 2018.

After completion of the successful phase 1 study, the Toca regimen showed a favorable safety profile, extended patient survival compared with other therapies, and provided complete tumor shrinkage.

In this study, patients will be randomized 1:1 to receive either standard of care treatment of single-agent chemotherapy (lomustine or temozolomide) or bevacizumab, or the Toca regimen. If a patient is randomized to the Toca regimen, their treatment will involve 2 parts. In the first step, patients receive vocimagene amiretrorepvec (Toca 511), a replicating virus that selectively infects cancer cells during surgery. The second step requires patients to receive cycles of extended-release 5-fluorocytosine (Toca FC), which is a potent anti-cancer pill that kills cancerous cells while activating immune cells selectively to fight off cancerous ones, leaving healthy cells unharmed.

“Toca 5 uses a virus to stimulate a patient’s own immune system and attack recurring high-grade gliomas— glioblastoma and anaplastic astrocytoma,” said Yaron Moshel, MD, PhD, neurosurgeon with Atlantic Neurosurgical Specialists and co-director of the Gerald J. Glasser Brain Tumor Center, the principal investigator for the local arm of the study in a statement.

With the current standard of care treatment, newly diagnosed patients have a median survival of approximately 14 to 16 months. After recurrence, this survival time falls to 7 to 9 months, on average.

Conversely, phase 1 results of the Toca regimen showed a median longevity of 14.4 months for patients with a recurrence.

“Patients with complete tumor shrinkage are still alive almost 3 years after starting the Toca regimen. These results are encouraging­— for patients, their loved ones, and the medical community– and we look forward to sharing further findings from phase 3 within the next 18 months,” said Moshel in a prepared remark.