This study enrolls patients that have been diagnosed with acute leukemia associated with a KMT2A (MLL) gene rearrangement (referred to as KMT2Arearranged, or KMT2A-R). The KMT2A-R leukemia has come back after treatment (relapsed) or is not responding to treatment (it is refractory). This study involves taking a study drug called SNDX-5613. The study is divided into two phases: one in which the study drug is given in combination with chemotherapy and a phase where the study drug is given alone. The purpose of the study is to test the safety of the study drug with chemotherapy, and how well the treatment regimen works for infants and young children with relapsed or refractory KMT2A-R leukemia.

This study involves an investigational cellular therapy called Afamitresgene Autoleucel. The overall goal of this study is to find out how safe and effective this cellular therapy is in treating people that have been diagnosed with synovial sarcoma, malignant peripheral nerve sheath tumors (MPNST), neuroblastoma or osteosarcoma that has grown or returned after being treated.

This study has several parts and involves taking a study drug called alpelisib. Some participants enrolled into Stage 2 will receive a placebo for the first part of the study (24 weeks) and will then receive the study drug. The purpose of this study is to find out if the study drug is safe and effective (can help) people with a confirmed diagnosis of lymphatic malformation (LyM) and a documented mutation in the PIK3CA gene

The purpose of this study is to find out if alpelisib (BYL719; the "study drug"), is safe and effective (can help) people who have PIK3CA-related overgrowth spectrum (PROS) disease.

This study enrolls patients with newly diagnosed differentiated thyroid cancer (papillary thyroid cancer or follicular thyroid cancer) that has spread to the lungs and has a genetic mutation called and NTRK fusion. The study involves taking a study drug called larotrectinib for approximately 6 months prior to receiving radioiodine therapy (RAI). The overall goal of this study is to find out if taking the study drug before RAI works better than receiving RAI alone (the usual standard of care treatment).

This study involves taking a study drug called lurbinectedin. The overall goal of this study is to see if different doses of lurbinectedin are safe and effective at treating children and young adults with recurrent or relapsed solid tumors, including Ewing Sarcoma.

This study involves taking a study drug called asciminib. The overall goal of the study is to find out how safe and effective the study drug is in treating people that have been diagnosed with Chronic Myeloid Leukemia (CML) and have not responded to treatment.

The purpose of the Phase 2 portion of this study is to evaluate the safety and efficacy of the study drug called palbociclib when given in combination with two other drugs (temozolomide and irinotecan) in patients with Ewing sarcoma and when given in combination with topotecan and cyclophosphamide in patients with neuroblastoma.

This study enrolls patients with refractory, progressive, or relapsed solid tumors. The purpose of this study is to find out whether a drug called PEEL-224 ("the study drug") is safe and effective when given as monotherapy (a drug given by itself) and as part of a combination therapy together with other chemotherapy drugs.

The purpose of this study is to test the safety and efficacy of the investigational drug called repotrectinib in children whose cancers have specific genetic changes (in the ALK, ROS1, or NTRK1-3 genes). This is the first study using this drug in children under 12 years of age. Repotrectinib is administered in capsule form or liquid suspension.