"Eliminating or neutralizing the tumor cells that are responsible for recurrence after medically induced tumor regression remains a seminal goal of cancer therapeutics. As such, these tumor initiating cells, so-called 'cancer stem cells', appear to be ideal targets for therapeutic intervention that could lead to long term disease free survival, better overall survival and potential cures," said Dr. Robert Dillman, Chief Medical Officer of CSC. "These cells express the repertoire of tumor associated antigens for each individual patient that need to be recognized by the patient's immune system. As such, this is a patient specific immunotherapy that addresses cancer heterogeneity and the origin of cancer recurrence, so it is potentially complementary to other cancer therapies, including other emerging enzyme-targeted agents and immunotherapies."
"T cells (a cell in your immune system) have always been thought to be capable of killing tumor cells, including autologous T cells of a patient with bulky cancer," said Dr. Andrew Pecora, Chief Visionary Officer of NeoStem and Chief Innovations Officer, Professor and Vice President of Cancer Services of the John Theurer Cancer Center at Hackensack University Medical Center. "It is now well established that tumors escape immune surveillance through inducing tolerance of autologous T cells. A new class of agent, so called T cell checkpoint inhibitors, has proven that unmasking tolerance allows autologous T cells to recognize and kill tumors in patients with a variety of tumor types including melanoma, lung cancer and renal cancer. However, even the best data presented to date combining two types of checkpoint inhibitors (e.g.: anti-CTLA-4 with anti-PD-1) in patients with melanoma did not improve outcomes for a significant percentage of patients treated and was associated with significant side effects. Lack of effect in part could be a result of insufficient targeting of melanoma initiating (stem) cells."
- These checkpoint inhibitors do not increase the immune response to antigens that the immune system has not recognized. The CSC patient-specific approach is designed to expand the number of "tumor stem cell" associated antigens that are recognized by that patient's immune system;
- The isolation and expansion of proliferating, self-renewing melanoma cells from a patient's tumor provides a source of highly enriched antigens expressed by the sub-population of melanoma cells that is most capable of re-establishing the tumor, leading to disease relapse and death. Following culture of the melanoma initiating (stem) cells, they are irradiated to further augment antigen presentation. The cells are then incubated with autologous dendritic cells to generate Melapuldencel-T which is administered with GM-CSF via subcutaneous injection. Irradiation of tumor cells and GM-CSF both enhance immune response to tumor antigens.
"Enhancement of immunologic targeting of melanoma initiating (stem) cells could significantly increase the incidence and durability of response as an immune-based therapy either alone or in combination with checkpoint inhibitors," said Dr. Dillman. "It is noteworthy that in the Phase 2 randomized trial, Melapuldencel-T improved outcomes in a broad spectrum of advanced melanoma patients. This same inclusive population will be the target of the Phase 3 program."