An Independent Data and Safety Monitoring Board (DSMB) unanimously recommended that the Phase 1/2 clinical trial evaluating VBI Vaccines’ VBI-1901 continue to enroll patients with recurrent glioblastoma (GBM) in a second study arm.
The positive review recommended the study continue without modification, after scanning through all safety data from the first group of patients, who received the lowest VBI-1901 dose. Enrollment now has commenced for the second, intermediate-dose study arm.
“We are encouraged by the safety profile of this candidate so far and are excited to continue enrollment in the intermediate dose cohort of this Phase 1/2a study, our first clinical study in immuno-oncology,” Jeff Baxter, VBI’s president and CEO, said in a press release.
Two additional DSMB reviews will take place for this trial — one after enrollment is complete in the intermediate-dose study arm, and another after the completion of enrollment in the high-dose study arm.
The study (NCT03382977) is a multi-site, open-label, dose-escalation study, testing VBI-1901 in approximately 28 patients with recurrent GBM. The study is divided into two main parts:
In Part A, researchers will escalate three doses of VBI-1901 to define the safety, tolerability and optimal dose level of the therapy candidate in recurrent GMB patients. About 18 patients should be enrolled in this phase.
A Part B will study the optimal dose level as defined in the Part A. This phase is expected to enroll about 10 additional patients. Patients in both phases will receive VBI-1901 every four weeks until tumor progression.
GBM tumors are susceptible to infection by cytomagalovirus (CMV), with more than 90 percent of these tumors producing CMV proteins. That’s why VBI developed VBI-1901 as a new cancer vaccine that targets two CMV proteins. These proteins are known to trigger strong immune responses, and are promising targets for immunotherapies.
In this manner, VBI-1901 stimulates the patient’s own immune system to identify and kill GBM cancer cells, in a more effective way than current standard of care.
Recent preclinical studies also seem to confirm that VBI-1901 could be a potent, “off-the-shelf” therapeutic vaccine.
VBI-1901 is administered inside the skin along with granulocyte-macrophage colony-stimulating factor (GM-CSF), a potent adjuvant that mobilizes dendritic cell — a kind of immune cell — function.
“In recurrent GBM, a devastating CMV-associated tumor, patients have few effective treatment options, and we believe that VBI-1901 has the potential to stimulate immune responses critical to boosting anti-tumor immunity,” Baxter said.