HS236

HS236 is a potent and highly selective small molecule inhibitor of Ataxia Telangiectasia and Rad3-related (ATR) protein kinase, developed by Zhejiang Hisun Pharmaceutical. ATR is a critical coordinator of the DNA damage response (DDR) pathway, specifically activated by replication stress and DNA double-strand breaks. By inhibiting ATR, HS236 disrupts cell cycle checkpoints and DNA repair mechanisms, leading to the accumulation of genomic instability and subsequent apoptosis in cancer cells. This mechanism is particularly effective in tumors with existing deficiencies in other DDR pathways, such as ATM or p53, through the principle of synthetic lethality. HS236 is currently undergoing Phase 1 clinical evaluation for the treatment of patients with advanced solid tumors.