Commercial-stage biopharmaceutical company VBI Vaccines has announced the dosing of the first patient in the second study arm in the ongoing Phase IIa clinical trial of VBI-1901, a cancer vaccine immunotherapeutic candidate.

Under this two-arm, open-label trial, 20 first-recurrent GBM patients will receive VBI-1901 along with either GM-CSF or AS01B, which is GlaxoSmithKline’s (GSK) adjuvant system, as immunomodulatory adjuvants.

VBI chief scientific officer David E Anderson said: “AS01B has been shown to boost T-cell mediated immunity and, building on the encouraging early immunologic and tumor response data we’ve seen to date from the VBI-1901 with GM-CSF study arm, we look forward to evaluating the benefit this combination could have for patients with GBM, a devastating disease with few treatment options.”

GSK Vaccines senior vice-president and R&D head Emmanuel Hanon said: “We are pleased that this study is now underway as this is the first time AS01B will be assessed in oncology for GBM patients in a clinical setting.”

The ongoing two-part trial is being carried out at The Neurological Institute of New York Columbia University Medical Center, Dana-Farber Cancer Institute, Massachusetts General Hospital, and the Ronald Reagan UCLA Medical Center.

The two-part Phase I/IIa study is a multi-centre, open-label, dose-escalation trial of VBI-1901 in up to 38 patients with recurrent GBM.

Under Part A, 18 patients with recurrent GBM were enrolled across three dose cohorts of VBI-1901: 0.4 µg, 2.0 µg, and 10.0 µg. Enrollment was completed in December 2018.

This was a dose-escalation phase that defined the safety, tolerability, and optimal dose level of VBI-1901 adjuvanted with granulocyte-macrophage colony-stimulating factor (GM-CSF) in recurrent GBM patients.

Part B of the trial was the subsequent extension of the optimal dose level, 10.0 µg, as stated in the Part A dose escalation phase.

This phase is a two-arm trial enrolling ten first-recurrent GBM patients in each arm, to assess 10.0 µg of VBI-1901 in combination with either GM-CSF or GSK’s AS01B adjuvant system as immunomodulatory adjuvants.

Patients in the study will receive the vaccine immunotherapeutic every four weeks until clinical disease progression.

Administered intradermally when adjuvanted with GM-CSF, VBI-1901 will be administered intramuscularly when adjuvanted with AS01B system.