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 Synovial Sarcoma Registry and Biospecimen Repository was opened in June of 2023 with the goal of furthering research and improving outcomes for patients with synovial sarcoma. This study is open to anyone treated in the United States. You do NOT have to travel to Philadelphia to participate.