CD200AR-L and Allogeneic Tumor Lysate Vaccine Immunotherapy for Recurrent HGG and Newly Diagnosed DMG/DIPG in Children and Young Adults

Inclusion Criteria:

• Histologically confirmed newly diagnosed DIPG/DMG with documented H3K27M alteration (based on IHC or DNA sequencing performed in a CLIA-certified laboratory) or recurrentHGG. Patients cannot enroll until they are a minimum of 14 days and preferably within 30 days from the last dose of radiation.
• Diagnosis of recurrent HGG based on MRI findings. Recurrent HGG must have receivedstandard of care radiation at diagnosis. Prior biopsy material will be required toconfirm diagnosis of HGG; however, biopsy of the recurrent/progressive lesion will notbe required for study enrollment.
• Maximal safe resection is preferred prior to clinical trial enrollment if indicatedand feasible.
• Clinically stable on a dose of corticosteroids not to exceed an equivalent ofdexamethasone 0.1 mg/kg/day (maximum 4 mg) for at least 2 weeks prior to studyenrollment.
• Prior therapy wash-out is required
• Minimum of 28 days since last dose of any targeted therapy (including bevacizumab),immunotherapy, investigational agents.
• Minimum of 10 days since any anti-cancer intervention: cytoreductive surgery/laserablation and a minimum of 28 days since any viral therapy
• Voluntary written consent obtained by patient if ≥18 years of age or a parent orguardian if <18 years of age before the performance of any study-related procedure notpart of standard medical care
• Able to comply with follow-up visit schedule (i.e., return to clinic for follow-upvisits).
• Willing to allow for collection of pre-treatment research related blood collection [1-5 mL red top tube and 2-10 mL green top tubes (or to a max of 2 ml/kg of bodyweight)] for immune characterization. If a patient does not subsequently enroll in thestudy, the samples will be destroyed according to institutional protocol.
• Lansky play performance score ≥60 (<16 years) or Karnofsky (≥16 years) performancescore of ≥60
• Sexually active persons of child-bearing potential or with partners of childbearingpotential must agree to use a highly effective form of contraception during the 2-yeartreatment period. Urine pregnancy tests will be obtained at defined time points duringprotocol therapy.
• Adequate bone marrow reserve: Absolute neutrophil (segmented and bands) count (ANC) ≥1.0 x 10E9/L, platelets ≥75 x 10E9/L; Hemoglobin ≥8 g/dL
• Hepatic: Bilirubin ≤1.3 mg/dL and SGPT (ALT) ≤2.5 x upper limit of normal (ULN) forage
• Renal: Normal serum creatinine for age or creatinine clearance >60 ml/min/1.73 mE2

Exclusion Criteria:

• Known sensitivity to the GBM6-AD tumor lysate vaccine, CD200AR-L, or imiquimod.
• Unable to complete a standard upfront course of radiotherapy due to diseaseprogression or intolerance of therapy.
• Radiographic evidence of diffuse leptomeningeal disease.
• Prior history of malignancy within 5 years of enrollment.
• Uncontrolled intercurrent illness including, but not limited to ongoing or activeinfection, symptomatic congestive heart failure, unstable angina pectoris, orpsychiatric illness/social situations that would limit compliance with studyrequirements.
• Concurrent use of tumor treatment field devices (e.g., Optune) - permitted until thetime of consent.
• History of any laboratory findings consistent with any uncontrolled immune systemabnormalities such as hyper-immunity (e.g., autoimmune diseases, thyroid dysfunction,lupus, scleroderma, etc.) and hypo-immunity [e.g., myelodysplastic disorders, marrowfailures, human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS),transplant immune-suppression, etc.]. Any known autoimmune disease must be clinicallysilent and without associated laboratory abnormalities for at least 1 year in theabsence of any disease directed therapy or systemic steroids.
• Any conditions that could potentially alter immune function (e.g., HIV/AIDS, hepatitisB, untreated hepatitis C, multiple sclerosis, renal failure).
• Receiving ongoing treatment with any immunosuppressive drug for any reason, excludingthose patients requiring a low dose of corticosteroids equivalent to dexamethasone 0.1mg/kg/day (maximum 4 mg) or less for treatment of tumor-related edema.
• Not able to tolerate an MRI or radiation therapy even with reasonable accommodationsor sedation.
• Known pregnancy or anticipated conception during the 1-year study period