Study of Efficacy and Safety of Dabrafenib in Combination With Trametinib in Pediatric Patients With BRAF V600 Mutation Positive LGG or Relapsed or Refractory HGG Tumors

Key Inclusion Criteria: * Diagnosis of BRAF V600 mutant High Grade glioma that had relapsed, progressed or failed to respond to frontline therapy * Diagnosis of BRAF V600 mutant Low Grade glioma with progressive disease following surgical excision, or non-surgical candidates with necessity to begin first systemic treatment because of a risk of neurological impairment with progression. * Confirmed measurable disease Key Exclusion Criteria: * Previous treatment with dabrafenib, trametinib, other RAF inhibitor, other MEK or ERK inhibitor * HGG patient: Cancer treatment within the past 3 weeks. LGG patient: Any systemic therapy or radiotherapy prior to enrollment * LGG patients: history of allergic reaction or contraindications to the use of carboplatin or vincristine * Stem cell transplant within the past 3 months * History of heart disease * Pregnant or lactating females