A Randomized Phase III Study Comparing Temporally-Modulated Pulsed Radiation Therapy (TMPRT) Versus Standard Radiation Therapy With Temozolomide for Adults With Newly Diagnosed MGMT-Unmethylated Glioblastoma

Summary

This phase III trial compares temporally-modulated pulsed radiation therapy versus standard radiation therapy in treating patients with newly diagnosed, IDH wildtype, MGMT-unmethylated glioblastoma. After completion of surgery, the standard of care for glioblastoma is radiation therapy. Radiation therapy uses high energy x-rays, particles, or radioactive seeds to kill cancer cells and shrink tumors. For older and frail patients, standard treatment also includes the chemotherapy drug temozolomide. Temozolomide is in a class of medications called alkylating agents. It works by damaging the cell's DNA and may kill tumor cells and slow down or stop tumor growth. Approximately 70% of glioblastoma patients have MGMT-unmethylated status. MGMT unmethylated tumors are less likely to respond to temozolomide chemotherapy, so there is more reliance on radiation therapy to kill the tumor cells. Recent clinical trials studying new therapies for MGMT-unmethylated glioblastoma have failed to improve outcomes over temozolomide. These recent studies also indicate that 80% of patients experience a decline in memory and thinking function after treatment. TMPRT differs from standard radiation therapy by delivering the same amount of radiation dose in 10-13 "pulses" with 3-minute breaks between pulses. TMPRT with temozolomide may work better than standard radiation therapy with temozolomide in increasing survival, as well as improving memory and thinking function in patients with newly diagnosed, IDH wildtype, MGMT-unmethylated glioblastoma.