Tesaro Files Suit Against AnaptysBio in Jemperli Dispute

Tesaro, Inc., a GSK subsidiary, announces that it has filed a lawsuit against AnaptysBio, Inc. in the Delaware Chancery Court. This action asserts that recent behavior of AnaptysBio significantly violates the current licensing agreement with Tesaro concerning the oncology medication Jemperli (dostarlimab).

The violation allows Tesaro to end the existing license agreement, secure a perpetual and irrevocable license for dostarlimab, and cut the royalties and milestone payments from Tesaro to AnaptysBio by 50%.

Tesaro has commenced this lawsuit after AnaptysBio alleged that Tesaro failed to meet specific obligations of the licensing agreement established in March 2014, and that AnaptysBio plans to cancel Tesaro’s license for dostarlimab. GSK and Tesaro strongly believe that these claims are completely unfounded.

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Jemperli is presently authorized in more than 35 nations for treating specific endometrial cancers, which is the most prevalent gynecological cancer in the United States. GSK and Tesaro have announced notable growth for Jemperli due to label extensions in endometrial cancer, particularly in the US and EU.

A strong and ambitious clinical trial initiative is underway to assess the potential application of dostarlimab in other cancers, such as rectal, colon, and head and neck. GSK is an international biopharmaceutical firm aimed at combining science, technology, and expertise to collaboratively combat disease