Neuro-Oncology publishes promising phase 2 results from Agenus’ brain cancer vaccine study

Dec 17 2013

Agenus Inc. (NASDAQ: AGEN), a biotechnology company developing novel immune system activating treatments for cancers and infectious diseases, today announced results published from a Phase 2 study demonstrated that more than 90% of the patients treated with Prophage Series G-200 were alive at six months after surgery and 30% were alive at twelve months. Additionally, the median overall survival was approximately eleven months. This compares favorably to the expected median survival for recurrent Glioblastoma multiforme (GBM) patients of three to nine months. The primary objective of this multi-center, single arm Phase 2 trial was to assess the survival rate at six months.

The data was published in a manuscript in Neuro-Oncology, the official journal of the Society of Neuro-Oncology. GBM is the most common and most aggressive form of primary brain cancer. Despite approved therapy patients with GBM face a poor prognosis. Prophage Series vaccines are currently being studied in both newly diagnosed and recurrent GBM.

"Glioblastoma tumors are often resistant to standard therapies and the extended survival observed in patients treated with Prophage Series vaccine is very promising," said Andrew Parsa, MD, PhD, corresponding author of the study and chair of neurological surgery at Northwestern Memorial Hospital and the Michael J. Marchese Professor and chair of the department of neurological surgery at the Feinberg School of Medicine at Northwestern University. "The next phase of development is underway with an NCI funded, large-scale, randomized trial investigating Prophage Series G-200 in combination with Avastin (bevacizumab). Avastin is approved for the treatment of recurrent GBM and we believe there is the potential for a synergistic effect of a targeted anti-tumor immunotherapy and anti-angiogenic agent that could benefit patients."

Prophage Series vaccines are individualized cancer vaccines. Each Prophage Series vaccine is manufactured using a patient's own tumor after surgical removal. Each vaccine contains the 'antigenic fingerprint' of the patient's particular cancer and is designed to activate the patient's immune system to specifically target and destroy cancer cells bearing this fingerprint.

Prophage Series G-200 Study Design

The Phase 2 trial enrolled 41 patients with a mean age of 55 years with surgically resectable recurrent high-grade GBM, the deadliest form of brain cancer. Patients underwent surgery to remove ≥90% of their tumors (also referred to as gross total resection), which were then used to manufacture Prophage Series G-200, a patient-specific heat shock protein based therapeutic vaccine. Eligible patients were treated after surgery with Prophage Series G-200 once weekly for four weeks, followed by biweekly injections until vaccine depletion. There were no serious adverse events associated with vaccine administration. For further information about this manuscript, please visit http://neuro-oncology.oxfordjournals.org.

The trial was supported through funding from the American Brain Tumor Association, Accelerated Brain Cancer Cure, National Brain Tumor Society, and National Cancer Institute Special Programs of Research Excellence. Dr. Parsa has not received any financial support or travel expense reimbursement for this work or for consulting activities on behalf of Agenus. Dr. Parsa does not have an equity interest in Agenus or a financial relationship with the company.

Avastin is a registered trademark of Genentech.