This study looks at a medicine called poly-ICLC (also called Hiltonol®) to treat a type of brain tumor called low-grade glioma (LGG) in kids who have a condition called NF1. NF1 is short for Neurofibromatosis Type 1, a genetic disorder that can cause tumors to grow on nerves. The goal is to see if poly-ICLC can help shrink these tumors over 48 weeks (about a year). The study will also look at how long kids stay cancer-free, any side effects, and other health benefits.

• The study is for kids under 22 who have tried at least one other treatment.
• Participants must go through tests to ensure they are healthy enough to join.
• Parents must agree to let their child participate and follow the study rules.

Kids can't join if they had radiation treatment before, are currently using other cancer treatments, or have certain health issues like active infections. The study will take place in several locations over a year. If you think your child might benefit, talk to your doctor about joining. Make sure they meet all the health requirements and understand the study process.