To carry out the assessment, VBI will add an arm to part B of its ongoing Phase I/IIa clinical trial being conducted in a total of 38 patients with recurrent glioblastoma (GBM), a type of brain tumour.
Part A of the multi-centre, open-label, dose-escalation trial was performed in 18 subjects to assess the safety, tolerability and optimal dose level of the vaccine immunotherapeutic. It involved 0.4µg, 2µg and 10µg doses.
Data from the first part demonstrated favourable tolerability of VBI-1901 adjuvanted with granulocyte-macrophage colony-stimulating factor (GM-CSF) at all dose levels.
In addition, three out of six patients treated with the 10µg dose showed evidence of stable disease, which was associated with vaccine-induced immune response.
This safety and immunogenicity data helped in determining the high dose as optimal for testing in the part B open-label extension phase, which will now comprise two arms of ten patients each.
Participants will be randomised to receive the VBI vaccine adjuvanted with GM-CSF or AS01B.
The company has already commenced enrolment for the GM-CSF arm and expects to recruit patients into the AS01B arm later this year after receiving approval from the US regulatory agency.
The vaccine will be given every four weeks until clinical progression in both parts of the trial.
GSK Vaccines senior vice-president and R&D head Emmanuel Hanon said: “This is the first time we have partnered with a biopharma company to evaluate AS01B in such a clinical setting and the first time this adjuvant will be assessed in oncology for GBM patients.
“We have shown the ability of AS01B to boost T-cell mediated immunity and believe the combination of AS01B and VBI-1901 could have benefits for patients with glioblastoma, a rare but devastating cancer.”