DIPG-35. BIOLOGICAL MEDICINE FOR DIFFUSE INTRINSIC PONTINE GLIOMA (DIPG) ERADICATION: RESULTS OF THE THREE ARM BIOMARKER-DRIVEN RANDOMIZED BIOMEDE 1.0 TRIAL

Despite 50 years of clinical trials, no improvement of survival has been observed in DIPG and most children die within 2 years of diagnosis. Only radiotherapy transiently controls disease progression. The study was conceived as a randomized multi-arm multi-stage program. It started with an open-label phase-II trial comparing three drugs (everolimus, dasatinib, erlotinib) combined with irradiation, allocated according to the presence of their specific targets (PTEN-loss, EGFR-overexpression) defined with a stereotactic biopsy after central confirmation of the diagnosis (presence of histone H3K27M mutation or loss of K27 trimethylation). Targeted therapies were started concomitantly with radiotherapy and were continued until disease progression. No biopsy-related death was reported and diagnostic yield was excellent, with only 5 non-informative biopsies. Biopsy excluded the diagnosisof DIPG in 8% of the cases. At the 3rd interim analysis, based on 193 randomized patients, the IDMC concluded that the study was unlikely to show a difference of OS between the 3 drugs even if 250 patients would be randomized. The median OS from the time of diagnosis was 11.9, 10.5 and 10 months for everolimus, dasatinib and erlotinib. Treatment was discontinued due to toxicity in 2%, 13%, and 15%, respectively. BIOMEDE shows the feasibility of biologically-driven treatment in DIPG on a large international scale. Based on the better toxicity profile and the slightly better efficacy, although not statistically significant, the steering committee proposed that everolimus should be used as the control arm for the next BIOMEDE 2.0 trial.