Ropidoxuridine as a Radiosensitizer in Newly Diagnosed IDH-Wildtype Glioblastoma With Unmethylated MGMT Promoter

This is a randomized, open-label, phase 2 study evaluating the safety and efficacy of oral ropidoxuridine as a radiation-sensitizing agent in patients with newly diagnosed wild-type isocitrate dehydrogenase glioblastoma with an unmethylated O6-methylguanine-DNA methyltransferase promoter, undergoing standard 60 Gy radiotherapy.

This is a randomized, open-label phase 2 study to assess the safety and efficacy of oral ropidoxuridine as a radiation sensitizing agent in patients with newly diagnosed wildtype isocitrate dehydrogenase glioblastoma with unmethylated O6-methylguanine-DNA methyltransferase promoter, receiving standard 60 Gy radiotherapy. In the dose optimization phase, a group of 40 patients will be evenly divided, with a 1:1 randomization, to receive ropidoxuridine for a duration of 7 weeks. They will be administered daily ropidoxuridine at two dose levels: either 960 mg or 1200 mg. This administration will occur 5 days a week, from Monday to Friday. Treatment with ropidoxuridine will start one week before radiotherapy (induction period) and continue concomitantly with 60 Gy standard radiotherapy fractionated in 2 Gy daily doses (Monday through Friday weeks 2 to 7, treatment period)), followed by a 4-week rest period. Following completion of this 11-week active study period, maintenance therapy, including temozolomide, tumor treating field device (Optune®), or other available treatment modalities, may be initiated at the discretion of the Investigator. Analysis of the pharmacokinetic, safety and tolerability data for the two cohorts will determine the optimal dose of ropidoxuridine, to be administered to the next cohort of 14 patients for determination of efficacy, compared to historical controls. A magnetic resonance imaging ( MRI) will be performed at the end of the active study period (Week 11). This MRI should not be used for disease assessment due to increased contrast enhancement in the acute radiation reaction phase, unless there is evidence of progression outside the radiotherapy fields. Radiographic disease assessment will be performed in accordance with community standard of care guidelines, every 3 months until disease progression. After the confirmed disease progression, survival monitoring follow-ups will occur every three months.