Repeated superselective intraarterial bevacizumab after blood brain barrier disruption for newly diagnosed glioblastoma: a phase I/II clinical trial.

PURPOSE

Pre-clinical evidence suggests bevacizumab (BV) depletes the GBM peri-vascular cancer-stem cell niche. This phase I/II study assesses the safety and efficacy of repeated doses of superselective intra-arterial cerebral infusion (SIACI) of BV after blood-brain barrier disruption (BBBD).

METHODS

Date of surgery was day 0. Evaluated patients received repeated SIACI bevacizumab (15 mg/kg) with BBBD at days 30 ± 7, 120 ± 7, and 210 ± 7 along with 6 weeks of standard chemoradiation. Response assessment in neuro-oncology criteria and the Kaplan-Meier product-limit method was used to evaluate progression free and overall survival (PFS and OS, respectively).

RESULTS

Twenty-three patients with a median age of 60.5 years (SD = 12.6; 24.7-78.3) were included. Isocitrate dehydrogenase mutation was found in 1/23 (4%) patients. MGMT status was available for 11/23 patients (7 unmethylated; 3 methylated; 1 inconclusive). Median tumor volume was 24.0 cm3 (SD = 31.1, 1.7-48.3 cm). Median PFS was 11.5 months (95% CI 7.7-25.9) with 6, 12, 24 and 60 month PFS estimated to be 91.3% (95% CI 69.5-97.8), 47.4% (26.3-65.9), 32.5% (14.4-52.2) and 5.4% (0.4-21.8), respectively. Median OS was 23.1 months (95% CI 12.2-36.9) with 12, 24, and 36 month OS as 77.3% (95% CI 53.6-89.9), 45.0% (22.3-65.3) and 32.1% (12.5-53.8), respectively.

CONCLUSIONS

Repeated dosing of IA BV after BBBD offers an encouraging outcome in terms of PFS and OS. Phase III trials are warranted to determine whether repeated IA BV combined with Stupp protocol is superior to Stupp protocol alone for newly diagnosed GBM.