Summary
This phase I/II trial tests the safety, side effects, and best dose of selinexor given in combination with standard radiation therapy in treating children and young adults with newly diagnosed diffuse intrinsic pontine glioma (DIPG) or high-grade glioma (HGG) with a genetic change called H3 K27M mutation. It also tests whether combination of selinexor and standard radiation therapy works to shrink tumors in this patient population. Glioma is a type of cancer that occurs in the brain or spine. Glioma is considered high risk (or high-grade) when it is growing and spreading quickly. The term, risk, refers to the chance of the cancer coming back after treatment. DIPG is a subtype of HGG that grows in the pons (a part of the brainstem that controls functions like breathing, swallowing, speaking, and eye movements). This trial has two parts. The only difference in treatment between the two parts is that some subjects treated in Part 1 may receive a different dose of selinexor than the subjects treated in Part 2. In Part 1 (also called the Dose-Finding Phase), investigators want to determine the dose of selinexor that can be given without causing side effects that are too severe. This dose is called the maximum tolerated dose (MTD). In Part 2 (also called the Efficacy Phase), investigators want to find out how effective the MTD of selinexor is against HGG or DIPG. Selinexor blocks a protein called CRM1, which may help keep cancer cells from growing and may kill them. It is a type of small molecule inhibitor called selective inhibitors of nuclear export (SINE). Radiation therapy uses high energy to kill tumor cells and shrink tumors. The combination of selinexor and radiation therapy may be effective in treating patients with newly-diagnosed DIPG and H3 K27M-Mutant HGG.