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Drug Development

Viking Therapeutics accuses competitor of pilfering proprietary information

The lawsuit concerns a small molecule that treats metabolic diseases

by Shi En Kim
January 9, 2023


The molecular strcuture of the drug candidate VK2809.

San Diego–based Viking Therapeutics has sued a group of companies, as well as their common founder and CEO, Jinzi Jason Wu, for allegedly stealing the trade secrets of a clinical-stage oral drug candidate.

The compound in question is VK2809, a liver-specific thyroid hormone receptor agonist. First developed around 2005, the drug candidate treats lipid and metabolic diseases such as nonalcoholic fatty liver disease. In 2014, Viking obtained a license to further develop the molecule, which is currently undergoing Phase 2 trials.

In 2016, China-based Ascletis BioScience initiated a meeting with Viking to discuss a potential collaboration around VK2809. Viking shared confidential information about its drug after extracting a confidential disclosure agreement from Ascletis, according to the lawsuit. No partnership resulted from the meeting.

Nevertheless, in 2019, Ascletis BioScience approached Viking again to propose another pact involving the same molecule. Under a similar confidentiality agreement, Ascletis perused Viking’s electronic files, but over a month into their review, Ascletis backed out of the partnership opportunity.

It was all “a ruse to steal Viking’s VK2809 trade secrets,” the complaint claims. Five months after the second meeting, Wu founded Gannex Pharma to develop a rival liver-disease drug. The lawsuit purports that Viking discovered the theft after the 2021 publication of Gannex’s patent applications related to the compound. Wu is listed as an inventor on these patents.

According to the lawsuit, Viking believes that the defendant’s drug, ASC41, is copied from Viking’s candidate. “Viking infers that ASC41 is Ascletis’s version of—if not the same compound as—VK2809,” the suit says.

Wu’s teams seemed to make significant headway in drug development after each of the Viking-Ascletis meetings, according to the lawsuit. As early as August 2018, Viking’s suit contends, Ascletis was working on a fatty liver disease drug, which it did not disclose during the 2019 meeting. By the second half of 2020, ASC41 had entered clinical trials. The tablet has completed five Phase 1 clinical trials in China and the US, with another two Phase 2 trials in the works.

Ascletis BioScience's parent company, Ascletis Pharma, denies any wrongdoing, claiming that ASC41 and a combination tablet were developed in-house. In a statement on its website, the company says it “believes that such allegations have no merit and will vigorously defend against the Complaints.”

Viking is seeking damages plus a permanent injunction against the defendants concerning its agonist technology.

Assertions of trade-secret theft from agreements that fall apart are not uncommon, says Rochelle Dreyfuss, a professor at the New York University School of Law who isn’t involved in the case. It is possible that defendants were working on a version of a drug similar to VK2809 before entering the confidentiality agreements and may have already developed the know-how that Viking shared during the meetings, she says.

If the judge rules to move the case forward, both sides will probably present evidence on the developmental timeline of their small molecules. Expect lab notebooks, she says.


This story was updated on Jan. 13, 2023, to correct the name of Ascletis BioScience. It was previously given as Ascletis Biosciences. The story was also updated to give the full name of Gannex Pharma instead of just Gannex. And a description of a statement by one of the defendants was updated to clarify that it is posted on the website of Ascletis BioScience's parent company, Ascletis Pharma, not the subsidiary.



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