Durability of single dose intra-arterial bevacizumab after blood/brain barrier disruption for recurrent glioblastoma

Background: Bevacizumab (BV) has been used to treat recurrent glioblastoma with a progression free survival of approximately 3-3.5 months. Typically, it is administered intravenously every 2-3 weeks at dosages ranging from 5-15 mg/kg. Serious side effects include GI tract perforations, hematologic disorders, intracranial hemorrhage, and malignant hypertension. We hypothesized that selective intracranial intra-arterial infusion (SIACI) of BV following blood/brain barrier disruption (BBBD) with mannitol may allow for reduced dosage, lower toxicity, and equivalent or superior progression free survival (PFS).

Methods: Sixteen patients (8 males & 8 females) with a mean age of 55 years (range 27-68), KPS>70, and recurrent glioblastoma were enrolled. All patients underwent super-selective catheterization and were given a single intra-arterial dose of 15 mg/kg BV following osmotic blood/brain barrier disruption with mannitol to the arteries supplying the tumor. The patients had no additional treatment following that initial SIACI mannitol and BV until they met criteria for progression. PFS was assessed using modified Response Assessment in Neuro-Oncology (RANO) criteria.

Results: Median progression free survival from only one dose of SIACI mannitol and BV was 3.9 months. Side effects included seizure in 2 patients, and headache in 1 patient. Seizures were well controlled with medications, and there were no serious toxicities. There were no endovascular-related complications.

Conclusion: SIACI of mannitol and BV at 15mg/kg allows for similar or better PFS compared to biweekly treatments of IV BV at 10mg/kg. The dosage required is lower and side effects were minimal and well tolerated. Future larger trials are warranted to assess whether repeated less frequent IA mannitol and BV may be superior to biweekly IV administration as a monotherapy.