Astex Pharmaceuticals is a research-driven biotechnology company specializing in the discovery and development of small‑molecule therapeutics, with a primary focus on oncology and other serious diseases. Founded in the United Kingdom, the company operates from Cambridge, England, with additional operations in Pleasanton, California. Since 2013, it has been a wholly owned subsidiary of Otsuka Pharmaceutical.
Astex is recognized for pioneering fragment‑based drug discovery and structure‑based design, integrating high‑throughput X‑ray crystallography, biophysics, and medicinal chemistry to identify and optimize novel compounds. The company advances its own pipeline and conducts discovery collaborations with major pharmaceutical partners. Its partnered research has contributed to approved cancer medicines, including the CDK4/6 inhibitor ribociclib (Kisqali) and the FGFR inhibitor erdafitinib (Balversa).
