Bevacizumab Plus Irinotecan Improves PFS in MGMT-positive Glioblastoma
Bevacizumab plus irinotecan significantly improved the 6-month progression-free survival rate and median progression-free survival.
Bevacizumab plus irinotecan significantly improved the 6-month progression-free survival (PFS) rate and median progression-free survival compared with temozolomide in patients with newly diagnosed glioblastoma who harbor a nonmethylated O6-methylguanine–DNA methyltransferase (MGMT) promoter, a study published in the Journal of Clinical Oncology has shown.1
Because patients with newly diagnosed glioblastoma who harbor a nonmethylated MGMT promoter receive limited efficacy from standard temozolomide, researchers sought to evaluate the efficacy of bevacizumab plus irinotecan and its impact on quality of life as an alternative to temozolomide.
For the multicenter, unblinded, phase 2 trial, researchers enrolled 182 patients. Participants were randomly assigned 2:1 to receive bevacizumab 10 mg/kg every 2 weeks during radiotherapy followed by maintenance bevacizumab plus irinotecan 125 mg/m2 every 2 weeks; or temozolomide 75 mg/m2 daily during radiotherapy followed by 6 cycles of temozolomide 150-200 mg/m2/day for 5 days every 4 weeks.
At progression, 81.8% of all patients who received second-line therapy in the temozolomide arm were given bevacizumab.
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Results showed that the 6-month progression-free survival rate was 79.3% (95% CI: 71.9-86.7) with chemoimmunotherapy compared with 42.6% (95% CI: 29.4-55.8) with temozolomide (P<.001). Furthermore, median progression-free survival was 9.7 months (95% CI: 8.7-10.8) and 5.99 months (95% CI: 2.7-7.3), respectively (P<.001).
However, there was no significant difference in median overall survival between the 2 treatment arms, possibly due to the high proportion of patients who received second-line bevacizumab.
There was also no difference in quality of life between the bevacizumab plus irinotecan arm and the temozolomide arm.
1. Herrlinger U, Schäfer N, Steinbach JP, et al. Bevacizumab plus irinotecan versus temozolomide in newly diagnosed O6-methylguanine–DNA methyltransferase nonmethylated glioblastoma: the randomized GLARIUS trial [published online ahead of print March 14, 2016]. J Clin Oncol. doi:10.1200/JCO.2015.63.4691.