MBCL-43. RECURRENT MEDULLOBLASTOMA – LONG-TERM SURVIVAL WITH A 'MEMMAT' BASED ANTIANGIOGENIC APPROACH

INTRODUCTION Patients with recurrent medulloblastoma have a poor prognosis with only around 8% of patients surviving at 5 years irrespective of salvage therapy used. We report on 29 patients from four institutions treated with a “MEMMAT” based antiangiogenic combination therapy. PATIENTS AND METHODS From 11/2006 to 06/2016, 29 patients were diagnosed with a recurrent medulloblastoma (19 first, 10 multiple recurrences). Median age at start of antiangiogenic therapy was 10 years (range 1–27). Subgroup of medulloblastoma was available in 18 patients and was group 3 or 4 in all except two (one WNT, one SHH-infant). For their current relapse patients received an antiangiogenic combination therapy consisting of bevacizumab, thalidomide, celecoxib, fenofibrate, and etoposide, alternating with cyclophosphamide and augmented with intraventricular therapy (etoposide and liposomal cytarabine). RESULTS As of 01/2020, 8/29 patients are alive at a median of 44 months after recurrence. 6/8 surviving patients are currently in CCR between 66 and 134 months after recurrence that prompted MEMMAT therapy. Two patients are again in remission after intercurrent relapses 105 and 102 months after first starting MEMMAT therapy. Five patients died of another cause (accident, leukemia, septicemia). OS (median 44 months) was 44±10% at 5 years and 39±10% at 10 years, PFS was 33±10% at 5 years and 28 ±9% at 10 years. Therapy was well tolerated and toxicities were manageable. CONCLUSION Our results suggest that antiangiogenic metronomic chemotherapy has clinical activity in recurrent medulloblastoma. Further investigation with an international phase II study is ongoing (MEMMAT; ClinicalTrials.gov Identifier: NCT01356290).