Study of the Effect NT-I7 on CD4 Counts in Patients With High Grade Gliomas

PRIMARY OBJECTIVES: Phase I: To determine the MTD (Maximum Tolerated Dose) and select optimal biological doses (OBD) of NT-I7 in HGG patients with severe lymphopenia Pilot Study: To test the effect of NT-I7 on CD4 counts compared to control SECONDARY OBJECTIVES: 1. To evaluate the optimal biological dose of NT-I7 2. To evaluate the effect of concurrent dexamethasone 3. To evaluate the duration of effect on CD4 counts (up to 6 months) 4. To evaluate the total lymphocyte counts over time and serial T cell lymphocyte subtypes and the effect on T cell repertoire (up to 6 months) 5. To evaluate the serial cytokine levels (up to 6 months) 6. To evaluate the impact of adjuvant temozolomide on NT-I7 effects on CD4 counts 7. To evaluate anti-drug antibodies 8. To evaluate the pharmacokinetic profile of NT-I7 after intramuscular administration in this patient population 9. To evaluate the safety and toxicity of NT-I7 in patients with high grade glioma OUTLINE: Patients are assigned to 1 of 2 groups depending on their use of dexamethasone. GROUP A: Patients not on dexamethasone (or equivalent of an alternative corticosteroid), or on a dose lower than a physiologic dose (=\< 0.75 mg daily) GROUP B: patients who require dexamethasone (or equivalent of an alternative corticosteroid) =\> 4 mg daily Patients must have been on the group assignment dose of corticosteroids for at least 5 days prior to the dose of NT-I7. Corticosteroid dose changes prior to the start of treatment are allowed as long as they do not alter patient's group assignment. PHASE I TREATMENT PLAN All patients (both Groups A and B) will be given a single dose of NT-I7 by intramuscular injection starting at 60 μg/kg, within one week after completing concurrent RT+TMZ and before starting adjuvant TMZ treatment, during the standard post-radiation break. Following this period, as per standard treatment, patients will go on to receive adjuvant temozolomide on Days 1-5 of 28-day cycles for 6 cycles. There should be about six weeks between the study injection and the start of adjuvant temozolomide; thus the start of adjuvant TMZ will be approximately two weeks later than the usual start, which is 4 weeks post-end of radiation. Patients who are delayed from receiving or are not able to receive adjuvant TMZ treatment may continue on study; adjuvant TMZ treatment is not a requirement for participation. PILOT STUDY TREATMENT PLAN GROUP A: participants will be given either a placebo (NT-I7 diluent) or one dose of NT-I7 at the Phase I Group A OBD by intramuscular injection within one week after completing concurrent RT+TMZ and before starting adjuvant TMZ treatment, during the standard post-radiation break. GROUP B: participants will be given one dose of NT-I7 at the Phase I Group B OBD by intramuscular injection within one week after completing concurrent RT+TMZ and before starting adjuvant TMZ treatment, during the standard post-radiation break. After completion of study treatment, patients are followed up every 2 months for 2 years and then every 6 months thereafter.