Pediatric Trial of Indoximod With Chemotherapy and Radiation for Relapsed Brain Tumors or Newly Diagnosed DIPG

Indoximod will be taken by mouth twice daily during radiation and throughout each chemo-immunotherapy treatment cycle.

Palliative low-dose or partial-field radiation plan (low-dose radiation or not all disease sites included).

Palliative full-dose radiation plan to all known sites of disease (\>50 Gy to brain, \>45 Gy to spine).

Temozolomide will be taken by mouth once daily, on days 1-5 of each chemo-immunotherapy treatment cycle.

Cyclophosphamide will be taken by mouth once daily, on days 1-21 of each chemo-immunotherapy treatment cycle.

Etoposide will be taken by mouth once daily, on days 1-21 of each chemo-immunotherapy treatment cycle.

Lomustine will be taken by mouth once daily, on day 1 of each chemo-immunotherapy treatment cycle.