Design, Synthesis, and Biological Evaluation of a Series of Spiro Analogues as Novel HPK1 Inhibitors

Hematopoietic progenitor kinase 1 (HPK1) negatively affects T cell activation and proliferation and is a promising target for immunotherapy. Although HPK1 inhibitors have shown promising efficacy in preclinical models, none have been approved for clinical use. One significant challenge in developing an HPK1 inhibitor is the difficulty in designing a potent inhibitor with good kinase selectivity and pharmacokinetic properties. Here, we report a series of spiro HPK1 inhibitors with good potency and selectivity. Specifically, compound