SP96

SP96 is a target-selective small molecule modulator of ERK1/2 signaling, specifically designed to address airway smooth muscle (ASM) hyperplasia and remodeling in chronic asthma. Developed through computational approaches by researchers at the University of Maryland and Thomas Jefferson University, SP96 binds to the FRS (substrate-binding domain) of ERK2 rather than the ATP-binding site, which helps minimize off-target effects associated with traditional ERK inhibitors. By selectively disrupting the ERK-mediated activation of the Activator Protein-1 (AP-1) transcription factor complex, SP96 downregulates key components such as FRA-1 and FosB, as well as the cell cycle regulator Cyclin D1. In preclinical models, SP96 has demonstrated the ability to inhibit PDGF-induced ASM cell proliferation and reduce alpha-SMA expression in 3D spheroid cultures without significant cytotoxicity.