A phase II study of thalidomide and irinotecan for treatment of glioblastoma multiforme

Purpose Irinotecan is a cytotoxic agent with activity against gliomas. Thalidomide, an antiangiogenic agent, may play a role in the treatment of glioblastoma multiforme (GBM). To evaluate the combination of thalidomide and irinotecan, we conducted a phase II trial in adults with newly-diagnosed or recurrent GBM. Patients and methods Thalidomide was given at a dose of 100 mg/day, followed by dose escalation every 2 weeks by 100 mg/day to a target of 400 mg/day. Irinotecan was administered on day 1 of each 3 week cycle. Irinotecan dose was 700 mg/m² for patients taking enzyme-inducing anticonvulsants and 350 mg/m² for all others. The primary endpoint was tumor response, assessed by MRI. Secondary endpoints were toxicity, progression-free survival, and overall survival. Results Twenty-six patients with a median age of 55 years were enrolled, with fourteen evaluable for the primary outcome, although all patients were included for secondary endpoints. One patient (7%) exhibited a partial response after twelve cycles, and eleven patients (79%) had stable disease. The intention to treat group with recurrent disease included 16 patients who had a 6-month PFS of 19% (95% CI: 4–46%) and with newly-diagnosed disease included 10 patients who had a 6-month PFS of 40% (95% CI: 12–74%). Gastrointestinal (GI) toxicity was mild, but six patients (23%) experienced a venous thromboembolic complication. Two patients had Grade 4 treatment-related serious adverse events that required hospitalization. There were no treatment-related deaths. Conclusion The combination of irinotecan and thalidomide has limited activity against GBM. Mild GI toxicity was observed, but venous thromboembolic complications were common.