Agenus (NASDAQ:AGEN) has extraordinary news. A recent analysis from a Phase 2 trial in patients with newly diagnosed glioblastoma multiforme (GBM) treated with Prophage Series G-100 (HSPPC-96) in combination with the current standard of care (radiation and temozolomide) showed an almost 18 month median progression free survival (PFS), which represents a 160% increase versus current standard of care alone. The results confirm continuation of the positive trends from the Phase 2 HSPPC-96 newly diagnosed GBM trial first reported at the 81st American Association of Neurological Surgeons (AANS) Annual Scientific Meeting in May 2013.
According to Andrew T. Parsa, MD, PhD, Lead Clinical Investigator and Chair of Neurosurgery at Northwestern Memorial Hospital and Northwestern University Feinberg School of Medicine, the results are extremely encouraging and justify a definitive randomized study. The patient-specificity and lack of toxicity, combined with patient selection to optimize immunotherapy efficacy, could position this vaccine as a breakthrough treatment for newly diagnosed GBM patients in the years ahead.
Agenus plans to hold an end of Phase 2 meeting with the FDA to discuss a Phase 3 trial that could potentially lead to marketing approval of the HSPPC-96 vaccine as a treatment for patients with newly diagnosed GBM.
The Phase 2 trial includes 46 patients treated with radiation and temozolomide as the standard of care in addition to HSPPC-96 vaccination. Data analysis demonstrates a median PFS of 17.8 months with 63% of the patients progression free at twelve months and 20% progression free at 24 months. These results score a considerable improvement when compared to patients treated with the standard of care (radiation plus temozolomide), which is 6.9 months.
The primary endpoint of the trial - Median overall survival (OS) - is 23.3 months and remained durable in patients treated with HSPPC-96. The 12 months survival rate is 85% with 50% of patients still alive and being followed, with many surviving beyond the 24 month study period. For the standard of care alone, median OS survival rate is 14.6 months.
The Phase 2 recurrent and newly diagnosed trials are being sponsored by Dr. Parsa and are primarily 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 expense reimbursement for this work or for consulting activities on behalf of Agenus. He does not have an equity interest in Agenus or a financial relationship with the company.
In addition to the Phase 2 newly diagnosed GBM trial, the Cancer Therapy Evaluation Program (CTEP) of the National Cancer Institute (NYSE:NCI) is supporting a study of the HSPPC-96 vaccine in a large, randomized Phase 2 trial in combination with bevacizumab (Avastin) in patients with surgically resectable recurrent GBM. Patients have already been randomized into this trial and active recruitment is underway at multiple centers in the US. The study is being sponsored by the Alliance for Clinical Trials in Oncology (ALLIANCE), a cooperative group of the NCI. This trial is the largest brain tumor trial ever funded by the NCI and the largest vaccine study ever conducted with Avastin.
The ALLIANCE trial is investigating the potential benefits of treatment with a combination of HSPPC-96 and bevacizumab in a three-arm study of approximately 222 patients with surgically resectable recurrent GBM using a primary endpoint of overall survival. The study will compare efficacy of the HSPPC-96 vaccine administered with bevacizumab either concomitantly or at progression, versus treatment with bevacizumab alone. This study design is supported in part by previous research indicating a potential synergistic effect between the mechanisms of action behind both HSPPC-96 and bevacizumab.
The ALLIANCE is composed of three NCI funded cooperative groups (American College of Surgeons Oncology Group [ACOSOG], Cancer and Leukemia Group B [CALGB], and North Central Cancer Treatment Group [NCCTG]). These three groups have been integrated in an effort to develop and conduct more efficient clinical research studies to bring clinical trial results to patients more quickly.
In addition to the newly diagnosed GBM study in Prophage Series G-100 and the ALLIANCE trial, a Phase 2 study testing the Prophage Series G-200 in patients with recurrent glioma has been completed. Agenus expects the final trial results of this study to be published in a scientific journal in 2014.
The above results bring news that many are hoping for, but were not expecting soon and from a small firm. Here we are, the good news has come at the hands of Agenus' Prophage Series vaccines. The vaccines contain a precise antigenic "fingerprint" of a patient's particular cancer and are designed to reprogram the body's immune system to target only those cells that bear this fingerprint, reducing the risk of affecting healthy tissue, causing debilitating adverse effects. The Prophage Series G vaccines are currently being studied in two different settings of newly diagnosed and recurrent glioblastoma.
This is great news as Glioblastoma is a vicious brain cancer that has poor prognosis and no effective treatment. The incidence rate has risen the past three decades. The current standard of care for patients with newly diagnosed GBM is surgical resection followed by fractionated external beam radiotherapy and systemic temozolomide resulting in a median OS of 14.6 months. No cure has been provided yet and most patients with GBM experience cancer recurrence with a median time to recurrence of seven months. There is no standard treatment for patients with recurrent GBM.
The American Cancer Society estimates that more than 23,000 malignant tumors of the brain or spinal cord will be diagnosed during 2013 in the US, and that more than 14,000 people will die from these tumors.
This is, indeed, good news.
Disclosure: Long AGEN.