PLX038 in Primary Central Nervous System Tumors Containing MYC or MYCN Amplifications

Background: About 90,000 new cases of brain and spinal cord tumors are diagnosed annually in the United States. Most of these tumors are benign; however, about 30% are malignant, and 35% of people with malignant tumors in the brain and spinal cord will die within 5 years. Many of these people have changes in certain genes (MYC or MYCN) that drive the development of their cancers. Objective: To test a study drug (PLX038) in people with tumors of the brain or spinal cord. Eligibility: People aged 18 years or older with a tumor of the brain or spinal cord. Some participants must also have tumors with changes in the MYC or MYCN genes. Design: Participants will be screened. They will have a physical exam and blood tests. They will have imaging scans and a test of their heart function. They may need to have a biopsy: A sample of tissue will be removed from their tumor. PLX038 is given through a tube attached to a needle inserted into a vein in the arm. All participants will receive PLX038 on the first day of each 21-day treatment cycle. They will take a second drug 3 days later to help reduce the risk of infection; for this drug, participants will be shown how to inject themselves under the skin at home. Blood tests, imaging scans, and other tests will be repeated during study visits. Hair samples will also be collected during these visits. Some participants may have an additional biopsy. Study treatment will continue up to 7 months. Follow-up visits will continue every few months for up to 5 years.