Shares of Agenus (AGEN) are up 15% premarket on modest volume in response to its report of positive results in a 46-patient Phase 2 clinical trial evaluating the safety and efficacy of its Prophage autologous cancer vaccine in patients with newly-diagnosed glioblastoma multiforme (GBM). In the study, 50% of patients lived for two years. This is significant because most patients with GBM die within one year. Prophage patients demonstrated a median overall survival of ~24 months. 33% of patients remain alive at 24 months and continue to be followed for survival. Median progression-free survival was almost 18 months which is 2 - 3x longer than patients treated with radiation and temozolomide alone. 22% of patients were alive without progression at 24 months and continue to be followed for survival.
The response to Prophage appeared to be more pronounced in patients with less expression of the checkpoint ligand PDL-1 on the white blood cells. This suggests that combining Prophage with PD-1 antagonists may make Prophage more effective in a greater percentage of GBM patients.