HJ891

HJ891 is a potent and highly selective small molecule inhibitor of Ubiquitin-Specific Protease 1 (USP1), developed by Chengdu Huajian Future Technology. USP1 is a deubiquitinating enzyme that plays a critical role in the DNA damage response (DDR) pathway, specifically in the deubiquitination of PCNA and FANCD2. By inhibiting USP1, HJ891 disrupts DNA repair mechanisms, leading to genomic instability and cell death in cancer cells, particularly those with existing deficiencies in homologous recombination repair (HRR), such as BRCA1/2 mutations. It is currently being evaluated in Phase 1 clinical trials for the treatment of advanced solid tumors.