Clinical outcomes with bevacizumab-containing and non-bevacizumab–containing regimens in patients with recurrent glioblastoma from US community practices

This analysis evaluated the efficacy and safety of bevacizumab as monotherapy and with irinotecan for recurrent glioblastoma in community-based practices. Adult patients with bevacizumab-naive, recurrent glioblastoma initiating second-line treatment (July 2006-June 2010) were identified using McKesson Specialty Health/US Oncology Network health records. Overall (OS) and progression-free survival (PFS) estimates were analyzed through July 2011 and compared for bevacizumab and non-bevacizumab regimens using the log-rank test. An adjusted Cox proportional hazards model assessed the effects of patient and treatment characteristics on outcomes. The analysis identified 159 patients initiating second-line treatment with a bevacizumab-monotherapy (n = 57), bevacizumab-combination (n = 79), or non-bevacizumab (n = 23) regimen. Patient characteristics were generally similar across groups. In the Cox analyses, OS (hazard ratio [HR] 0.51 [95 % confidence interval (CI) 0.31-0.82]; univariate medians: 8.86 vs. 5.19 months) was significantly longer with bevacizumab-containing regimens. Median PFS was longer with bevacizumab-containing regimens, but did not reach statistical significance (HR 0.64 [95 % CI 0.38-1.09]; univariate medians: 7.00 vs. 4.00 months). Analyses showed that each bevacizumab treatment group relative to non-bevacizumab had a reduced risk of death (bevacizumab-monotherapy regimen: HR 0.56 [95 % CI 0.31-1.03] and bevacizumab-combination regimen: HR 0.34 [95 % CI 0.21-0.68]). Patients receiving the bevacizumab-combination regimen trended toward longer OS and PFS than those receiving the bevacizumab-monotherapy regimen. Rates of bevacizumab-related toxicities were consistent with clinical trial reports.