NT-07 PHASE 1-2 DOSE-ESCALATION STUDY OF VB-111, AN ANTI-ANGIOGENIC GENE THERAPY, AS MONOTHERAPY AND IN COMBINATION WITH BEVACIZUMAB, IN PATIENTS WITH RECURRENT GLIOBLASTOMA

BACKGROUND: VB-111 is an anti-angiogenic agent consisting of a non-replicating adenovirus vector (Ad-5) with a modified murine pre-proendothelin promoter leading to apoptosis of tumor vasculature by expressing a fas-chimera transgene in angiogenic endothelial cells. Safety and efficacy of VB-111 alone and in combination with bevacizumab (BEV) were evaluated for patients with recurrent Glioblastoma (rGBM) in this phase 1-2 dose-escalation study. METHODS: VB-111 was administered as a single intravenous infusion at escalating doses from 1x1012 to 1x1013 viral particles (VPs), followed by repeat doses of 3x1012 or 1x1013 every 2 months. The protocol was amended to add-on BEV 10mg/Kg every 2 weeks upon further progression. Assessments included safety, pharmacokinetics, tumor response (RANO criteria) and overall survival (OS). RESULTS: Forty-six patients at 4 recruiting medical centers in the US and Israel received up to 13 repeat doses of VB-111. Of these 30 received the high dose (1x1013). There were 22 related adverse events, 19 CTCAE grade 1-2. The median OS was 360 [range: 70-574] and 266 days [range: 28-664] for patients receiving at least one high dose vs. subjects who received lower doses, respectively (p NS). Progression free survival was 63 vs. 55 days for patients who received high vs. lower doses, respectively (p = 0.01). Median follow-up was 232 days. Six patients had a partial response and/or prolonged disease stability ( greater than or equal to 180 days). Tumor growth rates showed a statistically significant dose response. Eleven patients received combination therapy of VB-111 with BEV after progression on VB-111 alone. Median time to second progression was 93 days. VB-111 was safe and well tolerated both as monotherapy and combined therapy. CONCLUSIONS: VB-111 was safe and well tolerated as monotherapy and in combination with BEV in patients with recurrent glioblastoma. Encouraging tumor growth attenuation and responses were seen. Overall survival was about 3 months longer than historical rGBM data.