Plexxikon Inc.

Plexxikon Inc. was a biotechnology company based in Berkeley, California, focused on discovering and developing small molecule pharmaceuticals. Founded in 2000 or 2001, the company utilized a proprietary platform that emphasized highly selective and targeted medicines. Plexxikon employed advanced techniques like high-throughput X-ray crystallography and structural proteomics to identify drug leads.

The company is known for its significant achievements, including the discovery of ZELBORAF® (vemurafenib), a treatment for mutation-specific melanoma, which was co-developed with Roche/Genentech and approved in over 40 countries. Another product, TURALIO®, was also developed by Plexxikon. The company supported various clinical and preclinical programs in areas such as oncology, CNS disorders, and autoimmune diseases.

Plexxikon formed strategic partnerships with major pharmaceutical companies, including Genentech/Roche and Wyeth Pharmaceuticals, to enhance its development efforts. In 2011, Plexxikon was acquired by Daiichi Sankyo for over $800 million. The company closed its office and research facility in March 2022, with some assets transitioning to Opna Bio, founded by former Plexxikon leaders.