FDA Grants Orphan Drug Designation to VBI-1901 for Patients Treatment of Glioblastoma

VBI-1901, a bivalent gB/pp65 immunotherapeutic vaccine candidate, has been granted orphan drug designation by the FDA for the treatment of patients with glioblastoma (GBM), according to a press release issued by VBI Vaccine Inc. This regulatory action comes on the heel of the FDA granting a fast track designation to VBI-1901 for the treatment of recurrent GBM in patients with first tumor recurrence.¹

A 2-part, dose-escalation study (NCT03382977) is currently evaluating the safety, tolerability, and optimal dose level of VBI-1901 in 38 patients with recurrent GBM.1Early data from 20 patients enrolled in the study were presented at the American Society of Clinical Oncology Annual Meeting and showed that VBI-1901 achieved tumor responses and good overall survival in patients. The 12-month OS rate observed with VBI-1901 was 60%, and the 18-month OS rate was 30%. Two durable responses were also observed among patients treated with VBI-1901 in the study. There was 1 patient who remained progression-free and on protocol after 2 years with a 93% reduction in tumor size.²

"This orphan drug designation is another significant milestone for our VBI-1901 program, and it underscores the urgency of our effort to develop meaningful new treatment options for patients with this devastating cancer," said Jeff Baxter, president, and chief executive officer of VBI, in a press release. "As recently presented at ASCO, we continue to see strong tumor response data and improvements in overall survival data compared to historical controls in the phase 2a study of VBI-1901. With this orphan drug status, we look forward to working closely with the FDA and clinical investigators to build on that data, advancing the potential of this program to be a valuable part of the fight against GBM."

The study will assess the primary end point of dose-limiting toxicity. The secondary end points of the study include the immunogenicity and optimal vaccine-induced immunity-serum IgG anti-gB antibodies, cellular immunity against HCMV gB and pp65 antigens, changes in frequencies of myeloid suppressors cells and regulatory T cell, progression-free survival, OS, median OS, decrease in steroid use compared with baseline, change in quality-of-life, and the immunogenicity of the optimal dose of VBI-1801 formulated with either granulocyte-macrophage colony-stimulating factor or AS01B adjuvants.³

Eligible patients are those between the ages of 18 and 70 years old with histological confirmed WHO grade IV glioblastoma. Patients are required to display unequivocal evidence of tumor recurrence as assessed by MRI of the brain, have recovered from surgery side effects and toxicity to prior therapies, and be stable or decreasing on a corticosteroid of 4 mg daily or higher for at least 5 days. In addition, patients must have a Karnofsky performance score of ≥ 70%, and adequate organ function to be eligible for inclusion in the study.

Female patients must have a negative pregnancy test within 14 days prior to starting VBI-1901 treatment, and contraception use is required throughout the study.

All patients are required to have a tumor specimen available for central pathological review to enroll in the study.

The study has moved on to the expansion phase and patients will be enrolled across sites in California, Massachusetts, and New York.

_REFERENCE:

_{1. VBI Vaccines receives U.S. FDA orphan drug designation for vbi-1901 for the treatment of glioblastoma. News release VBI Vaccines, Inc. June 22, 2022. Accessed June 23, 2022. https://bit.ly/3ne4RyO}

_{2. Wen PY, Reardon DA, Forst DA, et al. Evaluation of tumor responses and overall survival in patients with recurrent glioblastoma (GBM) from a phase IIa trial of a CMV vaccine immunotherapeutic candidate (VBI-1901). J Clin Oncol. 2022; 40;16 suppl 16: 2014-2014. doi: 0.1200/JCO.2022.40.16_suppl.2014}

_{3. Study to evaluate safety, tolerability, and optimal dose of candidate GBM vaccine VBI-1901 in recurrent GBM subjects. Clinicaltrials.gov. Updated October 12, 2021. Accessed June 23, 2022. https://bit.ly/3HP6xrG}