rHSC-DIPGVax Plus Checkpoint Blockade for the Treatment of Newly Diagnosed DIPG and DMG

This study tests a new cancer vaccine (rHSC-DIPGVax) combined with checkpoint blockade immunotherapy drugs for children and young people newly diagnosed with DIPG (diffuse intrinsic pontine glioma) or DMG (diffuse midline glioma) — aggressive brain cancers with very limited treatment options. **You may be eligible if...** - Your child has been newly diagnosed with DIPG or DMG (a specific type of brainstem or midline brain tumor) - Diagnosis is confirmed by biopsy or by MRI imaging that meets standard criteria - Your child is between 12 months and 18 years old - Your child has adequate physical strength (Karnofsky or Lansky score ≥50) **You may NOT be eligible if...** - Your child has already received treatment for this brain tumor - The diagnosis does not meet criteria for DIPG or DMG - Your child has serious medical conditions that would prevent participation - Your child is too frail or underweight for the study Talk to your doctor to see if this trial is right for you.