Guardant Health hit with $83M verdict in TwinStrand DNA sequencing patent lawsuit

The cancer blood test developer Guardant Health is on the hook to pay $83.4 million following a jury’s verdict this week in a federal patent case lodged by TwinStrand Biosciences and the University of Washington. 

The nucleus of the case involves multiple patents on DNA sequencing methods that were developed by TwinStrand’s former CEO, Jesse Salk, M.D., Ph.D., while he was a medical student at the university, alongside his colleagues. 

The Seattle-based TwinStrand holds an exclusive license to the technology—which it describes as capable of being 10,000 times more accurate than typical next-generation sequencing, by independently checking both strands of DNA and matching them up to eliminate reading errors—which the company uses to underpin its blood plasma tests for detecting rare and hard-to-spot genetic mutations linked to different cancers.

TwinStrand first filed a lawsuit against Guardant in August 2021. In its complaint, the company claimed Guardant’s sequencing technologies and tests had infringed on its patents through its Guardant360 blood and tissue kits. TwinStrand would launch its first commercial DuplexSeq kit in 2020.

In the meantime, Guardant had aimed to counter the suit by petitioning the U.S. Patent and Trademark Office’s Patent Trial and Appeal Board—asking for additional reviews of the validity of UW’s patents, and whether they should have been issued in the first place.

Guardant had said that redundant readings of DNA and the use of barcoding molecules to catch sequencing errors were commonplace approaches, and used by other companies such as Pacific Biosciences. However, the PTAB’s final decision, issued in early October of this year, found in favor of TwinStrand and the university, and ultimately allowed the patents to stand.

A month later, the jury in Delaware federal district court followed suit—finding that Guardant owed $83.4 million in royalty payments, for a figure equal to 6% of about $1.4 billion in Guardant revenues.

Guardant has said it plans to appeal not only the jury’s decision, but also the PTAB’s findings and will bring the latter to the federal circuit court of appeals.

“We strongly disagree with this decision and will vigorously appeal for its overturn,” Guardant co-founder and co-CEO Helmy Eltoukhy said in a statement regarding the Delaware verdict. “We believe the ruling ignores the strengths and merits of our R&D and intellectual property, which we painstakingly developed for over a decade.”