Summary

This phase III trial compares the effect of selumetinib versus the standard of care treatment with carboplatin and vincristine (CV) in treating patients with newly diagnosed or previously untreated low-grade glioma (LGG) that does not have a genetic abnormality called BRAFV600E mutation and is not associated with systemic neurofibromatosis type 1. Selumetinib works by blocking some of the enzymes needed for cell growth and may kill tumor cells. Carboplatin and vincristine are chemotherapy drugs that work in different ways to stop the growth of tumor cells, either by killing the cells or by stopping them from dividing. The overall goal of this study is to see if selumetinib works just as well as the standard treatment of CV for patients with LGG. Another goal of this study is to compare the effects of selumetinib versus CV in subjects with LGG to find out which is better. Additionally, this trial will also examine if treatment with selumetinib improves the quality of life for subjects who take it.

Objectives

PRIMARY OBJECTIVE:
I. To demonstrate that the efficacy of treatment with selumetinib as measured by event-free survival (EFS) is non-inferior compared to treatment with carboplatin/vincristine (CV) in previously-untreated low-grade glioma (LGG) not associated with BRAFV600E mutations or systemic neurofibromatosis type 1 (NF1).

SECONDARY OBJECTIVES:
I. To estimate tumor response rates to each regimen of chemotherapy.
II. To evaluate visual acuity (VA) outcomes utilizing Teller Acuity Cards (TAC) and HOTV letter acuity testing in previously-untreated optic pathway gliomas (OPGs).
III. To describe the improvement in motor function as measured by the Vineland Scale in children with previously-untreated LGG that have motor deficits at enrollment.
IV. To estimate the difference in EFS and tumor response rate between BRAF rearranged and non-BRAF rearranged patients treated on each chemotherapy regimen.
V. To prospectively evaluate the quality of life of children with LGG not associated with BRAFV600E or systemic NF1 treated with either CV or selumetinib.
VI. To prospectively evaluate the cognitive, social, emotional, and behavioral functioning of children with LGG not associated with BRAFV600E or systemic NF1 treated with either CV or selumetinib.

EXPLORATORY OBJECTIVE:
I. To obtain paired blood and tumor specimens for future biology studies, including studies to correlate genomic drivers to response.

OUTLINE: Patients are randomized to 1 of 2 arms.

ARM I:
INDUCTION: Patients receive vincristine sulfate intravenously (IV) over 1 minute on days 1, 8, 15, 22, 29, 36, 43, 50, 57, and 64, and carboplatin IV over 60 minutes on days 1, 8, 15, 22, 43, 50, 57, and 64 in the absence of disease progression or unacceptable toxicity. Patients also undergo collection of blood and magnetic resonance imaging (MRI) at baseline and end of induction.

MAINTENANCE: Patients receive vincristine sulfate IV over 1 minute on days 1, 8, and 15, and carboplatin IV over 60 minutes on days 1, 8, 15, and 22. Treatment repeats every 42 days for up to 8 cycles in the absence of disease progression or unacceptable toxicity. Patients also undergo collection of blood and undergo MRI at baseline, throughout the trial, and during follow up.

ARM II: Patients receive selumetinib sulfate orally (PO) twice daily (BID) on days 1-28. Treatment repeats every 28 days for up to 27 cycles in the absence of disease progression or unacceptable toxicity. Patients also undergo collection of blood and undergo MRI at baseline, throughout the trial, and during follow up.

After completion of study treatment, patients are followed up every 3 months for year 1, every 6 months for years 2-3, and then annually for years 4-10.

Eligibility

1. Patients must be >= 2 years and =< 21 years at the time of enrollment
2. Patients must have a body surface area (BSA) of >= 0.5 m^2 at enrollment
3. Patients must have non-neurofibromatosis type 1 (non-NF1) low-grade glioma (LGG) without a BRAFV600E mutation as confirmed by Rapid Central Pathology and Molecular Screening Reviews performed on APEC14B1 (NCT02402244) and that has not been treated with any modality besides surgery. Note: Patients may be newly-diagnosed OR previously diagnosed, and there is no required time frame between biopsy/surgery and treatment initiation. * Patients with residual tumor after resection or progressive tumor after initial diagnosis (with or without surgery) who have not received treatment (chemotherapy and/or radiation) are eligible * Patients must have two-dimensional measurable tumor >= 1 cm^2 to be eligible
4. Eligible histologies will include all tumors considered low-grade glioma or low-grade astrocytoma (World Health Organization [WHO] grade I and II) by 5th edition WHO classification of central nervous system (CNS) tumors with the exception of subependymal giant cell astrocytoma
5. Patients with metastatic disease or multiple independent primary LGG are eligible
6. Creatinine clearance or radioisotope glomerular filtration rate (GFR) >= 70 mL/min/1.73 m^2 OR a serum creatinine based on age/gender as follows (performed within 7 days prior to enrollment): * Age: Maximum Serum Creatinine (mg/dL) * 2 to < 6 years: 0.8 mg/dL (male); 0.8 mg/dL (female) * 6 to < 10 years: 1 mg/dL (male); 1 mg/dL (female) * 10 to < 13 years: 1.2 mg/dL (male); 1.2 mg/dL (female) * 13 to < 16 years: 1.5 mg/dL (male); 1.4 mg/dL (female) * >= 16 years: 1.7 mg/dL (male); 1.4 mg/dL (female)
7. Total bilirubin =< 1.5 x upper limit of normal (ULN) for age (performed within 7 days prior to enrollment) (children with a diagnosis of Gilbert’s syndrome will be allowed on study regardless of their total and indirect [unconjugated] bilirubin levels as long as their direct [conjugated] bilirubin is < 3.1 mg/dL)
8. Serum glutamic pyruvic transaminase (SGPT) (alanine aminotransferase [ALT]) =< 135 U/L (performed within 7 days prior to enrollment). For the purpose of this study, the ULN for SGPT is 45 U/L
9. Albumin >= 2 g/dL (performed within 7 days prior to enrollment)
10. Left ventricular ejection fraction (LVEF) >= 53% (or institutional normal; if the LVEF result is given as a range of values, then the upper value of the range will be used) by echocardiogram (performed within 4 weeks prior to enrollment)
11. Corrected QT (QTc) interval =< 450 msec by electrocardiography (EKG) (performed within 4 weeks prior to enrollment)
12. Absolute neutrophil count >= 1,000/uL (unsupported) (performed within 7 days prior to enrollment)
13. Platelets >= 100,000/uL (unsupported) (performed within 7 days prior to enrollment)
14. Hemoglobin >= 8 g/dL (may be supported) (performed within 7 days prior to enrollment)
15. Patients with a known seizure disorder should be stable and should not have experienced a significant increase in seizure frequency within 2 weeks prior to enrollment
16. Patients 2-17 years of age must have a blood pressure that is =< 95th percentile for age, height, and gender at the time of enrollment (with or without the use of anti-hypertensive medications)
17. Patients >= 18 years of age must have a blood pressure =< 130/80 mmHg at the time of enrollment (with or without the use of anti-hypertensive medications)
18. Note for patients of all ages: Adequate blood pressure can be achieved using medication for the treatment of hypertension
19. All patients must have ophthalmology toxicity assessments performed within 4 weeks prior to enrollment
20. For all patients, a magnetic resonance imaging (MRI) of the brain (with orbital cuts for optic pathway tumors) and/or spine (depending on the site(s) of primary disease) with and without contrast must be performed within 4 weeks prior to enrollment
21. Patients must have a performance status corresponding to Eastern Cooperative Oncology Group (ECOG) scores of 0, 1, or 2. Use Karnofsky for patients > 16 years of age and Lansky for patients =< 16 years of age
22. Patients must have the ability to swallow whole capsules
23. All patients have signed an appropriate consent form and Health Insurance Portability and Accountability Act (HIPAA) authorization form (if applicable)
24. All patients and/or their parents or legal guardians must sign a written informed consent
25. All patients have been consented and enrolled on APEC14B1 (NCT02402244) followed by enrollment on the ACNS1833 Pre-Enrollment Eligibility Screening (Step 0) on the same day to complete the Rapid Central Review
26. All institutional, Food and Drug Administration (FDA), and National Cancer Institute (NCI) requirements for human studies must be met