This is a Phase 1 multicenter study of pevonedistat in combination with Temozolomide and Irinotecan in pediatric patients with refractory solid tumors, including CNS tumors and lymphoma. The study treatment is considered experimental because pevonedistat is not approved by the United States (US) Food and Drug Administration (FDA) for treating pediatric patients with refractory solid tumors, including CNS tumors and lymphoma. The purpose of this study is to estimate the maximum tolerated dose (MTD) and/or recommended Phase 2 dose (RP2D) of pevonedistat administered in combination with...