Patterns and Efficacy of Bevacizumab Use Across Treatment Lines in Glioblastoma

Aim: Use of bevacizumab in the management of glioblastoma multiforme (GMB) remains controversial. Currently in Canada, it is approved for recurrent GBM treatment. We describe the use of bevacizumab and analyses the efficacy across treatment lines in GBM. Methods: Patients (pts) diagnosed GBM (primary or secondary) from 2008-2014 and treated with bevacizumab were identified at McGill University Hospitals; demographics, diagnosis, and treatment pattern were collected via chart review. Primary endpoints were median progression-free survival (PFS) and overall survival (OS) estimated via Kaplan-Meier method. Secondary endpoint was toxicity. Grading of adverse events (AEs) were in accordance to CTCAE 4.0 criteria. Results: 64 pts were identified and their files were analyzed (40 males; median age at diagnosis 54 years, range 26-83). Majority had KPS score ≥70 (n = 56, 87.5%). 49 (76.6%) pts had primary and 15 (23.4%) had secondary GBM. Available MGMT testing was performed in 24 pts (methylated n = 10, 15.6%; unmethylated n = 14, 21.9%). 30 (46.9%) received bevacizumab in 1st line and 34 (53.1%) 2nd line and beyond (2L+). The median duration of bevacizumab in 1st line 36.6 weeks and 2L+ 14.21 weeks (overall 24.4 weeks; range Conclusions: Our results show bevacizumab treatment may be more efficient after a recurrence than when used in the beginning of treatment and are in line with reported registration trials data. Disclosure: All authors have declared no conflicts of interest.