VBI Vaccines Inc. (Nasdaq: VBIV and TSX: VBV) (“VBI”) today announced that it is developing a novel therapeutic vaccine candidate for medulloblastoma. The Meghan Rose Bradley Foundation, a pediatric brain cancer advocacy organization, has provided a grant to perform initial research to evaluate VBI’s immunotherapy candidate in ex vivo studies using medulloblastoma patient samples.
“We are grateful to the Meghan Rose Bradley Foundation for their support in helping to advance our understanding of this devastating pediatric cancer,” said Dr. David E. Anderson, Ph.D., VBI’s Chief Scientific Officer. “Immunotherapy may represent an attractive treatment option for medulloblastoma that stimulates the patient’s own immune system to identify and attack tumor cells, while sparing the vulnerable surrounding brain that is still developing in children.”
Medulloblastoma is the most common malignant primary brain tumor in children.1 Standard of care treatment begins with surgical removal of the tumor, and is often followed by chemotherapy and radiation, depending on the patient’s age and staging.2 Current treatments have led to improvements in survival, however, the risk of recurrence as well as the long-term side effects associated with surgery and radiation underscore the urgent need for new therapeutic approaches.3
Developing a medulloblastoma immunotherapy requires the identification of antigens, used to direct the immune response, that are consistently expressed on tumor cells. Recent research has demonstrated that medulloblastoma tumors are particularly susceptible to infection by cytomegalovirus (“CMV”), with over 90% of some medulloblastoma tumors expressing CMV antigens.4 In addition, antiviral therapies that inhibit CMV replication have been shown to reduce medulloblastoma tumor cell growth, both in vitro and in vivo, suggesting that CMV may increase the malignancy of infected cells.5
VBI has developed VBI-1901, a bivalent therapeutic vaccine candidate designed to direct an immune response against gB and pp65, two CMV antigens that are highly immunogenic targets during natural infection. VBI-1901 includes granulocyte-macrophage colony-stimulating factor (“GM-CSF”), an adjuvant that mobilizes dendritic function and enhances Th1-type immunity.6 In addition to medulloblastoma, VBI is assessing VBI-1901 for use in treating glioblastoma multiforme (“GBM”); GBM tumors are also highly susceptible to infection by CMV.7 VBI intends to have a pre-IND meeting with the U.S. FDA to discuss its GBM immunotherapy candidate in late June or early July of this year.
VBI is evaluating the ability of VBI-1901 to stimulate CD4+ and CD8+ T cell responses in peripheral blood mononuclear cells (“PBMCs”) harvested from healthy patients and patients with medulloblastoma; CD4+ and CD8+ immune responses are critical to efficacious anti-tumor immunity. VBI will also monitor several biomarkers predictive of clinical efficacy.
The Meghan Rose Bradley Foundation was established to honor the memory of Meghan Bradley, who passed away in 2004 shortly after being diagnosed with medulloblastoma. The organization promotes pediatric brain cancer awareness, education, and advocacy and seeks to raise funds for novel research.