This study involves taking a study drug called BA3011. The overall goal of this study is to see if BA3011 is a possible treatment for patients with sarcoma.

This is a clinical trial for patients with neuroblastoma that has returned (relapsed) or has not responded to standard treatment. The patients will have a biopsy of their tumor that will be tested for genetic changes and then matched to available drugs. If the results from the testing show molecular features in the tumor that allow for study treatment, patients will be invited for further testing to see if they are eligible for new treatments. Experimental therapies are all taken orally and may consist of one drug or a combination of drugs

This study enrolls patients that have been diagnosed with acute myeloid leukemia (AML), myelodysplastic syndrome (MDS), or mixed phenotype acute leukemia (MPAL) that has either come back (relapsed) or does not respond to therapy (refractory). This study involves taking a drug called uproleselan that is not yet approved for use in children or adults. The purpose of the study is to find a safe dose of the study drug in children that can be given with standard chemotherapy without causing severe side effects.