P14.124 EORTC 1709/CCTG CE.8: A phase III trial of marizomib in combination with standard temozolomide-based radiochemotherapy versus standard temozolomide-based radiochemotherapy alone in patients with newly diagnosed glioblastoma

Abstract BACKGROUND The standard of care for patients with newly diagnosed glioblastoma includes maximal debulking surgery followed by radiotherapy (RT), and concomitant as well as maintenance therapy with the alkylating agent, temozolomide (TMZ). However, the prognosis remains poor and novel treatment strategies are urgently needed. Targeting the proteasome has been considered a promising anti-cancer approach for several years. Marizomib is a novel, irreversible and pan-proteasome inhibitor, which crosses the blood-brain barrier and has been assessed in phase I trials in patients with newly diagnosed or recurrent glioblastoma. MATERIAL AND METHODS EORTC 1709/CCTG CE.8 is a randomized, controlled, open label phase III superiority trial. Patients with histologically confirmed newly diagnosed glioblastoma and a performance status >70 are eligible. Patients are randomized in a 1:1 ratio to receive standard of care (TMZ/RT→TMZ) alone or TMZ/RT→TMZ plus marizomib. The study aims at enrolling 750 patients. Stratification factors include study site, age, performance status and extent of resection. The primary objective of this trial is to compare overall survival in patients receiving marizomib in addition to standard of care with those receiving standard treatment only. The testing strategy specifies the determination of this objective in the intent-to-treat population as well as the subgroup of patients with MGMT-unmethylated tumors. Secondary endpoints include progression-free survival, safety, neurocognitive function and quality of life. A translational research program has been set up. The study will be activated at approximately 50 EORTC sites across Europe, 25 sites in Canada and additional sites in the US. Patient recruitment started in June 2018 and as of April 29, 2019, a total of 164 patients have been randomized. An update on the enrolment status will be provided at the EANO meeting. ClinicalTrials.gov Identifier: NCT03345095