Plexxikon Wins Patent Infringement Case against Novartis

  • Jury Upholds Validity of Patent Claims, Issues Damages Award of $178 Million, and Finds Infringement was Willful

Berkeley, CA—July 22, 2021—Plexxikon, a member of the Daiichi Sankyo Group and a leader in structure-guided discovery and development of novel small molecule pharmaceuticals, today announced that it has won its patent infringement lawsuit against Novartis. In a jury trial at the U.S. District Court for the Northern District of California, Novartis conceded infringement and sought to invalidate Plexxikon’s patents covering Tafinlar® on the grounds of anticipation, written description and enablement. The jury rejected Novartis’s arguments, upheld the validity of Plexxikon’s patents, and found Novartis’s infringement was willful. Plexxikon was awarded damages of $178 million for past infringement of its patents and will receive additional royalty payments for future sales of Tafinlar® in the United States through the life of the patents.

“We are delighted with the jury’s verdict which validates Plexxikon’s pioneering role in the field of BRAF inhibitors and enables proper credit for our proprietary discovery efforts,” said Chao Zhang, PhD, chief executive officer. “Genus patents —like those in the lawsuit —are routinely used to prevent competitors from knocking-off our scientific innovations with slight molecular changes. We are gratified that the jury upheld their validity, protecting our investment so that we can continue discovering and developing innovative new drugs for patients in need.”

Tafinlar® was developed by GSK and acquired by Novartis for $2.4B. Tafinlar® is a BRAF inhibitor that is approved for the treatment of metastatic melanoma, adjuvant melanoma, non-small cell lung cancer and anaplastic thyroid cancer. Tafinlar® also competes with Zelboraf®, another BRAF inhibitor that was discovered by Plexxikon and licensed to Roche.  

In the suit, Plexxikon alleged that Novartis owed the company substantial royalties on its drug Tafinlar®, which infringes two Plexxikon patents (U.S. Patent Nos. 9,469,640; and 9,844,539).

About Plexxikon
Plexxikon, a member of the Daiichi Sankyo Group since April 2011, is a leader in the structure-guided discovery and development of novel small molecule pharmaceuticals to treat human disease. The company’s drug Zelboraf® (vemurafenib/PLX4032) was approved by the FDA in 2011, and Turalio® (pexidartinib/PLX3397) was approved by the FDA in 2019. Plexxikon is developing a portfolio of preclinical and clinical-stage compounds to address significant unmet medical needs in oncology and other therapeutic areas. Plexxikon’s Scaffold-Based Drug Discovery™ platform integrates multiple state-of-the-art technologies, including the use of X-ray crystallography as an early screening tool that provides a significant advantage over other drug discovery approaches. For more information, please visit

About Daiichi Sankyo
Daiichi Sankyo is dedicated to creating new modalities and innovative medicines by leveraging our world-class science and technology for our purpose “to contribute to the enrichment of quality of life around the world.” In addition to our current portfolio of medicines for cancer and cardiovascular disease, Daiichi Sankyo is primarily focused on developing novel therapies for people with cancer as well as other diseases with high unmet medical needs. With more than 100 years of scientific expertise and a presence in more than 20 countries, Daiichi Sankyo and its 16,000 employees around the world draw upon a rich legacy of innovation to realize our 2030 Vision to become an “Innovative Global Healthcare Company Contributing to the Sustainable Development of Society.” For more information, please visit

Susan Kinkead 
Kinkead Communications

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