VBI-1901 10µg plus GM-CSF had a disease control rate of 44% among 16 patients with recurrent glioblastoma in a phase 1/2a study.
Vaccination with VBI-1901 was linked to T-cell activation capable of trafficking across the blood-brain barrier to the tumor microenvironment among patients with recurrent glioblastoma (GBM), according to additional biomarker data from a phase 1/2a study (NCT03382977).1
Findings were presented at the 28th Annual Meeting and Education Day of the Society for Neuro-Oncology (SNO) and showed that among the 16 patients in the VBI-1901 10µg plus GM-CSF study arms, the disease control rate (DCR) was 44% (n =7). There were 2 partial responses observed, including in 1 patient who received treatment for over 28 months, surviving at least 40 months as of August 1, 2023. This patient had a maximum tumor reduction of 93% relative to baseline.
Another 5 patients had stable disease for a sustained period of time and all patients with a tumor response (n = 7) reached a minimum survival of 12 months. Compared with the median overall survival (OS) of 8 months with monotherapy standard of care, the median OS was 12.9 months with VBI-1901.
“We are very pleased to share these significant mechanistic findings at SNO,” said David E. Anderson, PhD, chief scientific officer of VBI Vaccines, Inc., in a press release.1 “The GBM tumor microenvironment is notoriously immunosuppressive and difficult to penetrate, which is why most treatment needs to be administered intratumorally, and why there are currently so few effective treatment options for patients.”
Higher blood/plasma levels of C4G were observed among patients treated with VBI-1901 who achieved partial tumor responses compared with patients with stable or progressive disease. After vaccination with VBI-1901, higher levels of C4G were also associated with longer progression-free survival (PFS) rates.
VBI-1901 is a novel cancer vaccine immunotherapeutic candidate currently under investigation for patients with recurrent GBM. VBI-1901 has already been granted a fast track designation and an orphan drug designation from the FDA for this patient population.
A phase 2b study is ongoing to further evaluate VBI-1901 in patients with first recurrent GBM. The multi-center, randomized, controlled, open-label study will include up to 60 patients who will be randomized in a 1:1 fashion across to receive either intradermal VBI-1901 plus GM-CSF at a dose of 10 µg every 4 weeks until disease progression, or monotherapy standard-of-care, consisting of intravenous carmustine or oral lomustine every 6 weeks until disease progression or intolerable toxicity.2
Investigators are assessing the end points of OS, tumor response rate, PFS, safety, tolerability, immunologic responses, reduction in corticosteroid use relative to baseline, and change in quality-of-life compared with baseline.
“We believe that these data continue to enrich the potential for VBI-1901 to have meaningful impact in recurrent and primary GBM, and we look forward to data from the next phases of development in each setting,” added Anderson, in a press release.1