The efficacy of temozolomide for recurrent glioblastoma multiforme

Background and purpose The efficacy of temozolomide ( TMZ ) in recurrent glioblastoma multiforme ( GBM ) has been evaluated by several clinical trials. A meta‐analysis to assess the overall efficacy of TMZ in the treatment of recurrent GBM was carried out by the authors. Methods Medline, EMBASE database and the C ochrane L ibrary were searched for relevant studies. Eligible studies were clinical trials of recurrent GBM s assigned to TMZ with data on efficacy including tumor response, progression‐free survival ( PFS ) or overall survival ( OS ) available. The overall efficacy was calculated using a random‐effects or fixed‐effects model, depending on the heterogeneity of the included trials. Results A total of 15 phase II clinical trials including 902 recurrent GBM s were analyzed. The overall clinical benefit rate was 50.5% (95% CI : 44.3–56.7%) with significant difference between metronomic and standard schedules of TMZ (61.4% vs. 46.3%, P = 0.037). The overall 6‐month PFS ( PFS ‐6) rate was found to be 27.8% (95% CI : 22.7–33.5%) with significant difference between metronomic and standard schedules (33.1% vs. 20.1%, P < 0.001). In addition, significant difference in PFS ‐6 was detected between high (average daily dose >100 mg/m 2 ) and low (average daily dose ≤100 mg/m 2 ) dose metronomic schedules ( RR = 1.57, 95% CI : 1.17–2.09, P = 0.002). The overall 6‐month OS ( OS ‐6) and 12‐month OS ( OS ‐12) rates were 65.0% (95% CI : 57.4–71.9%) and 36.4% (95% CI : 26.9–47.1%) separately. There was no significant difference in OS ‐6 between metronomic and standard schedules ( P = 0.266); however, a trend was noted favoring the metronomic schedule for OS ‐12 ( P = 0.089). Conclusions Temozolomide is effective for recurrent GBM s, and its efficacy may be increased with metronomic schedule and high average daily dose (>100 mg/m 2 ).