Testing the Addition of an Anti-cancer Drug, DT2216, to the Usual Chemotherapy Treatment for Relapsed or Refractory Solid Tumors and Fibrolamellar Carcinoma

This phase I/II trial tests the safety, side effects and best dose of DT2216 in combination with irinotecan and how well it works in treating children, adolescents and young adults with solid tumors and fibrolamellar cancer that has come back after a period of improvement (relapsed) or that has not responded to previous treatment (refractory). DT2216 is an anti-apoptotic protein B-cell lymphoma-extra large targeted protein degrader. It may stop the growth of tumor cells by blocking Bcl-xL, a protein needed for tumor cell survival. Irinotecan is in a class of antineoplastic medications called topoisomerase I inhibitors. It blocks a certain enzyme needed for cell division and deoxyribonucleic acid repair and may kill tumor cells. Giving DT2216 in combination with irinotecan may be safe, tolerable, and/or effective in treating children, adolescents and young adults with relapsed or refractory solid tumors or fibrolamellar cancer.