Study of Lenvatinib in Combination With Everolimus in Recurrent and Refractory Pediatric Solid Tumors, Including Central Nervous System Tumors

Inclusion Criteria

• ≥2 years and 16 year of age and Lansky play score ≥50 for participants ≤16 years of age. Neurologic deficits in participants with CNS tumors must have been relatively stable for at least 7 days prior to study enrollment. Participants who are unable to walk because of paralysis, but who are up in a wheelchair, will be considered ambulatory for the purpose of assessing the performance score
• Prior Therapy
• Participants must have fully recovered from the acute toxic effects of all prior anti-cancer therapy
• Cytotoxic chemotherapy or other chemotherapy known to be myelosuppressive: ≥21 days after the last dose of cytotoxic or myelosuppressive chemotherapy (42 days if prior nitrosourea)
• Anti-cancer agents not known to be myelosuppressive (eg, not associated with reduced platelet or absolute neutrophil counts): ≥7 days after the last dose of agent
• Monoclonal antibodies: ≥21 days or 3 half-lives (whichever is shorter) of the antibody must have elapsed after the last dose of a monoclonal antibody (including checkpoint inhibitors). Toxicity related to prior antibody therapy must be recovered to Grade ≤1
• Corticosteroids: If used to modify immune adverse events related to prior therapy, ≥14 days must have elapsed since last dose of corticosteroid. Participants receiving corticosteroids, who have not been on a stable or decreasing dose of corticosteroid for at least 7 days prior to enrollment, are not eligible
• Hematopoietic growth factors: ≥14 days after the last dose of a long-acting growth factor or 7 days for short-acting growth factor. For agents that have known adverse events occurring beyond 7 days after administration, this period must be extended beyond the time during which adverse events are known to occur
• Interleukins, interferons, and cytokines (other than hematopoietic growth factors): ≥21 days after the completion of interleukins, interferons or cytokines (other than hematopoietic growth factors)
• Stem cell infusions (with or without total body irradiation): Allogeneic (non-autologous) bone marrow or stem cell transplant, or any stem cell infusion including donor leukocytes infusion or boost infusion: ≥84 days after infusion and no evidence of graft versus host disease; Autologous stem cell infusion including boost infusion: ≥42 days
• Cellular Therapy: ≥42 days after the completion of any type of cellular therapy (eg, modified T cells, natural killer cells, dendritic cells, etc)
• Radiotherapy (XRT)/External Beam Irradiation including Protons: ≥14 days after local XRT; ≥150 days after total body irradiation, craniospinal XRT or if radiation to ≥50% of the pelvis; ≥42 days if other substantial bone marrow radiation.
• Radiopharmaceutical therapy: ≥42 days after systemically administered therapy.
• Vascular endothelial growth factor (VEGF)/VEGF receptor (VEGFR)-targeted or mammalian target of rapamycin (mTOR)-targeted therapies: Must not have received prior exposure to lenvatinib; May have previously progressed on an mTOR inhibitor; No more than 2 prior VEGF/VEGFR-targeted therapies (For Phase 2 only); Must not have received prior VEGF/VEGFR-targeted therapy in combination with an mTOR inhibitor (For Phase 2 only)
• Adequate bone marrow function for participants with solid tumors without known bone marrow involvement
• Adequate bone marrow function for participants with known bone marrow metastatic disease
• Adequate renal function
• Adequate liver function
• Adequate cardiac function
• Adequate neurologic function
• Adequate blood pressure (BP) control with or without antihypertensive medications
• Adequate coagulation
• Adequate pancreatic function
• Adequate metabolic function
• Adequate glycemic control
• Participants must have a minimum body surface area (BSA) of 0.6 m^2 at study entry.

Exclusion Criteria

• Participants who have had or are planning to have the following invasive procedures
• Major surgical procedure, laparoscopic procedure, open biopsy or significant traumatic inju