Kronos Bio, Inc., a clinical-stage biopharmaceutical company, focuses on the discovery and development of small molecule therapeutics to treat cancer and other serious diseases in the United States. It is developing KB-9558, a p300 KAT inhibitor development candidate which is in preclinical development for the treatment of multiple myeloma, as well as HPV-driven tumors; and KB-7898, a p300 KAT inhibitor, which is in preclinical development for the treatment of Sjogren's disease. The company was incorporated in 2017 and is headquartered in San Mateo, California. As of June 20, 2025, Kronos Bio, Inc. operates as a subsidiary of Concentra Biosciences, LLC.