Onartuzumab plus bevacizumab versus placebo plus bevacizumab in recurrent glioblastoma (GBM): HGF and MGMT biomarker data.

Abstract

2015 Background: The phase II GO27819 study assessed the monovalent MET inhibitor, onartuzumab, plus the anti-VEGF antibody, bevacizumab (O+B) versus placebo plus bevacizumab (P+B) in recurrent GBM. Exploratory univariate biomarker analyses correlated efficacy with levels of the MET ligand HGF and MGMT methylation. Methods: GBM patients (pts) at first recurrence after chemoradiation were randomized 1:1 to receive O (15 mg/kg, q3w) + B (15 mg/kg, q3w) or P+B until progression. Primary endpoint: progression-free survival (PFS); secondary endpoints: overall survival (OS), objective response rate (ORR), safety; exploratory endpoint: biomarker analysis. Baseline tumor HGF levels were quantitatively assessed by cobas PCR; MGMT methylation was assessed by Quantitative Methylation Specific PCR. Results: In the ITT group (64 O+B, 65 P+B) no difference in PFS, OS or ORR was seen between the arms. A total of 119 pts (58 O+B, 61 P+B) had HGF-PCR results and 110 (56 O+B, 54 P+B) had MGMT data. Assessing the P+B arm on...