SD-2301

SD-2301 is a preclinical, highly potent, and selective heterobifunctional proteolysis-targeting chimera (PROTAC) designed to degrade signal transducer and activator of transcription 3 (STAT3). Developed by researchers at the University of Michigan, the molecule links a high-affinity STAT3-binding ligand to a Von Hippel-Lindau (VHL) E3 ubiquitin ligase ligand, facilitating the ubiquitination and subsequent proteasomal degradation of STAT3. In preclinical studies, SD-2301 demonstrated a DC50 of approximately 4 nM and a Dmax exceeding 95%, showing significantly greater potency than earlier degraders like SD-36 and SD-91, as well as KT-333. In mouse xenograft models of lymphoma, melanoma, and colon cancer, a single intravenous dose of SD-2301 induced complete and durable tumor regression. Additionally, in immune-competent models, SD-2301 enhanced dendritic cell and CD8+ T cell function, synergizing with anti-PD-L1 therapy to suppress tumor growth.