The subject receives the study drug administration and neutron irradiation in the BNCT clinic with all procedures performed under the control by the investigator affiliated to the study site. 500 mg/kg of the study drug is intravenously administered over 3 hours at a constant rate and neutron irradiation starts at 1 hour after the end of the study drug administration according to the previously established neutron irradiation plan.~All patients will be evaluated for response using magnetic resonance imaging (MRI) using RANO and modified RANO criteria.
This is a multi-centered, radiation dose escalation, open, exploratory, Phase 1/2a clinical trial on the safety, efficacy and pharmacokinetic characteristics of BNCT in patients with recurrent high-grade gliomas.~The Phase I clinical study is to explore the adequate radiation dose level of BNCT based on confirmation of the maximum tolerated dose (radiation dose) of BNCT in patients with recurrent high-grade gliomas and characterize the safety, efficacy and pharmacokinetics.~To evaluate the primary objective of tolerability, subject population with history of exposure to a similar treatment recurrent high-grade glioma who received prior standard radiotherapy will be recruited.~The Phase IIa is to confirm the efficacy and safety after irradiation of radiation dose confirmed in the Phase I clinical study. To evaluate the primary objective of efficacy, subject population with glioblastoma (The 2021 WHO Classification of Tumors of the Central Nervous System, Glioblastoma IDH-wild type, WHO Grade 4) will be recruited.