HLX97-053

HLX97-053 is a novel, oral small molecule inhibitor targeting lysine acetyltransferase 6A and 6B (KAT6A/B) developed by Shanghai Henlius Biotech. It was identified alongside HLX97-069 as a top candidate with potent enzymatic inhibition and enhanced selectivity against KAT5/7/8. In preclinical models, HLX97-053 demonstrated dose-dependent antitumor efficacy in ZR-75-1 breast cancer xenografts and exhibited strong synergistic effects when combined with fulvestrant and palbociclib in CDK4/6 inhibitor-resistant patient-derived xenograft (PDX) models. It is being developed for the treatment of advanced or metastatic solid tumors, particularly estrogen receptor-positive (ER+) breast cancer.