Seclidemstat mesylate (SP-2577) is a highly effective and reversible inhibitor of KDM1A (LSD1), with a Ki of 31 nM and an IC 50 of 13 nM. It demonstrates significant potential in promoting antitumor immunity in switch/sucrose nonfermentable (SWI/SNF) complex mutated ovarian cancer, while also exhibiting inhibitory effects on virus production, viral DNA replication, and late gene expression. Seclidemstat mesylate is a valuable tool for studying Ewing Sarcoma in research settings.