ACTR-26. SAFETY AND EFFICACY OF BEVACIZUMAB PLUS TTFIELDS IN PATIENTS WITH RECURRENT GLIOBLASTOMA (GBM): DATA FROM A PHASE II CLINICAL TRIAL

Abstract

BACKGROUND: Studies of bevacizumab monotherapy and TTFields monotherapy have shown activity but limited clinical benefit in patients with recurrent GBM. In an open label, single-arm, phase 2 clinical trial, the safety and efficacy of the combination of bevacizumab and TTFields was studied in patients with recurrent GBM. METHOD(S): Bevacizumabnaive patients with histologically confirmed GBM or other grade IV glioma, with recurrent disease after radiotherapy and temozolomide chemotherapy, were eligible. Bevacizumab dose was 10mg/kg intravenously every 2 weeks and TTFields was worn at least 18 hours daily. The primary endpoint was safety, progression-free survival at 6 months (PFS6) and overall survival at 12 months (OS12). Treatment was continued until disease progression or unacceptable toxicity. Survival outcomes were assessed using the Kaplan- Meier method. Treatment-related adverse events were reported according to CTCAE, v4.0 criteria. RESULT(S): 25 patients were enrolled and 23 were eligible for data analysis: 18 (78%) men and 5 (22%) women, median age 60 years (range 17-78). 21 patients were Caucasian, 1 was African American and 1 of unknown race. Median follow-up was 6.0 months (range 2.4-22). Seven patients (30 %) had disease progression. Median PFS was 9.9 (95% CI: 6.7-NA) months. PFS rate at 6 months (PFS6) was 71% (95% CI: 0.54- 0.94). Median overall survival was 9.9 (95%CI 7.3-NA) months. OS rate at 12 months (OS12) was 42% (95%CI 0.24-0.74). 7 patients (30%) had grade 3 toxicity (cough, dysphagia, muscle weakness, hyperglycemia, hypertension, psychosis, seizure, lymphopenia, transaminitis). 1 patient developed grade 4 muscle weakness in the lower extremities. CONCLUSION(S): Treatment with the combination of bevacizumab and TTFields in patients with recurrent GBM is safe and feasible and has shown clinical efficacy.