Study of Avelumab in Combination With Lenvatinib for Children With Primary CNS Tumors

Inclusion Criteria

• •Participants with histologically confirmed diagnosis of primary CNS malignancy as follows: a) Primary CNS tumors: the tumor should be considered high-grade histologically; prior radiotherapy is allowed; participants must have progressed after at least 1 prior systemic therapy, except for those with diffuse midline glioma with or without the H3 K27M mutation. b) Specific for participants with diffuse midline glioma with or without the H3 K27M mutation: prior radiotherapy is allowed; no more than 1 prior systemic therapy is allowed; participants with diffuse midline glioma with or without the H3 K27M mutation who have not received prior systemic therapy but have prior radiotherapy only are allowed to enroll
• •On screening scans, measurable disease by RANO criteria
• •Participants must have a Lansky performance status \>= 50 for age \<= 16 years or Karnofsky performance status \>= 50 for age \> 16 years at Screening
• •Participants who have received major surgery (including but not limited to neurosurgical resection, brain biopsy, or radiation to the primary brain tumor) within 28 days prior to the first dose of study interventions
• •Participants with history of intracranial hemorrhage/spinal cord hemorrhage within 28 days prior to the first dose of study interventions