RRx-001 Given With Irinotecan and Temozolomide for Pediatric Patients With Recurrent or Progressive Malignant Solid and Central Nervous System Tumors

Inclusion Criteria: 1. Recurrent or progressive malignant (World Health Organization (WHO) grade 3 or 4 tumors) primary brain or spinal cord tumors and solid tumors (excluding lymphomas) 2. Eligible patients may have measureable or non-measurable but evaluable disease according to the reviewed Response Evaluation Criteria in Solid Tumors (RECIST) guidelines version 1.1 criteria. 3. Patients must have a Karnofsky score of ≥50% if \>16 years old or a Lansky score of ≥50 if ≤16 years old 4. Patients must have fully recovered from the acute treatment-related toxicities (defined as \<grade 1) of their most recent prior anti-neoplastic therapy prior to study enrollment. 5. Patients must be at least 4 weeks from major surgery including craniotomy or tumor debulking/resection and at least 1 week from stereotactic biopsy prior to study enrollment. Patients must have fully recovered from all acute effects of prior surgical intervention excluding central line placement prior to study enrollment. Patients must have fully recovered from all acute effects of central line placement prior to initiation of study treatment. 6. Patients with neurological deficits should have deficits that are stable for a minimum of 7 days prior to study enrollment. Patients with seizure disorders may be enrolled if the seizures are well-controlled with a stable seizure frequency and duration for a minimum 7 days. 7. Patients on chronic systemic steroids must be on a stable or decreasing dose for at least 7 days prior to study enrollment. If used to modify immune adverse events related to prior therapy, ≥ 14 days must have elapsed since last dose of corticosteroid. 8. Platelet count ≥75,000/mm3. Patient must be transfusion independent defined as not receiving platelet transfusions with a 7-day period prior to study enrollment. 9. Peripheral absolute neutrophil count ≥1000/mm3 10. Creatinine clearance or radioisotope glomerular filtration rate (GFR) ≥50 mL/min/1.73 m2 or a serum creatinine based on age and sex 11. Conjugated bilirubin ≤1.5 times the institutional laboratory's upper limit of normal 12. Alanine aminotransferase (ALT) (serum glutamic-pyruvic transaminase (SGPT)) ≤3 times the institutional laboratory's upper limit of normal 13. Aspartate transaminase (AST) (serum glutamic-oxaloacetic transaminase (SGOT)) ≤3 times the institutional laboratory's upper limit of normal 14. Adequate pulmonary function defined as: 15. Oxygen saturation as measured by pulse oximetry \> 93% on room air 16. No evidence of dyspnea at rest 17. Left ventricular ejection fraction \> 50% 18. Patients of child-bearing potential of both genders must utilize contraception including but not limited to hormonal contraception, barrier method, or abstinence for the duration of the study and 28 days after completion of study. 19. Patients must have a central line in place prior to administration of the first dose of RRx-001. Patients must have fully recovered from all acute effects of central line placement prior to initiation of study treatment. 20. The patient or parent/legally authorized representative is able to understand the consent and is willing to sign a written informed consent document according to institutional guidelines. Assent, when appropriate, will be obtained according to institutional guidelines. 21. Patients must be able to safely take oral medications either as liquid or tablet. Exclusion Criteria: 1. Pregnant or breast feeding females 2. Patients with the following conditions will be excluded from study enrollment: cyanotic heart disease, intermediate or severe β-thalassemia, known glucose-6-phosphate dehydrogenase (G6PD) deficiency, active infections, concurrent malignancy, a known thrombophilia syndrome, or a personal history of venous thromboembolism including catheter-associated thrombi.31-34 Additionally, patients with clinically significant or poorly controlled cardiac, pulmonary, hepatic, or other organ dysfunction that, in the opinion of the investigator, would compromise the patient's ability to tolerate protocol therapy, put them at additional risk for toxicity, or interfere with the study procedures or results are not eligible for study enrollment. Patients with a known coagulopathy or bleeding diathesis or who have undergone either a solid organ or allogeneic bone marrow/stem cell transplant are not eligible for study enrollment. 3. Patients taking concurrent anti-cancer or investigational drug therapies are not eligible for study enrollment. 4. Patients taking anti-oxidants including alpha lipoic acid, vitamin E, N- acetylcysteine, and omega 3 fatty acid supplements are not eligible for study enrollment. Patients must be off these drugs for a minimum of 7 days prior to study enrollment and must remain off anti-oxidant medications for the duration of study treatment. 5. While on study, concomitant use of clozapine, echinacea, leflunomide, natalizumab, and tofacitinib are prohibited due to potential for increased temozolomide toxicity. 6. Patients who have received drugs that are strong inducers of CYP3A4 within 14 days prior to study enrollment are not eligible. 7. Patients who in the opinion of the investigator are unwilling or unable to return for required follow-up visits or obtain follow-up studies required to assess toxicity to therapy or to adhere to drug administration plan, other study procedures, and study restrictions are not eligible for study enrollment.