Anaptys Initiates Litigation Against Tesaro, a GSK Subsidiary

Core Viewpoint - AnaptysBio has filed a Verified Complaint against Tesaro and GSK, alleging material breaches of their Collaboration Agreement and seeking legal remedies [1][2]. Group 1: Legal Dispute - The Complaint asserts that Tesaro breached the Collaboration Agreement by engaging in clinical trials with competing PD-1 antagonists, including Keytruda, and failed to use reasonable efforts to maximize commercial returns for Jemperli [2]. - Anaptys previously filed a complaint against GSK in 2020 for similar breaches related to GSK's clinical trial of Zejula in combination with Keytruda, which resulted in a settlement that included cash payments and increased royalties on Jemperli [3]. - Tesaro has initiated its own lawsuit against Anaptys, claiming that Anaptys has breached the Collaboration Agreement, which Anaptys contends is without merit [4]. Group 2: Collaboration Agreement Details - The Collaboration Agreement, established in March 2014, involves Tesaro developing Jemperli for various solid tumor indications [6]. - Anaptys is entitled to royalties from Jemperli sales, structured as 8% for net sales below $1 billion, 12% for sales between $1 billion and $1.5 billion, 20% for sales between $1.5 billion and $2.5 billion, and 25% for sales above $2.5 billion [7]. - A one-time $75 million commercial sales milestone is anticipated once Jemperli achieves $1 billion in worldwide net sales [7]. Group 3: Financial Implications - The royalty term under the Collaboration Agreement extends until the expiration of composition of matter coverage, which is set to expire in 2035 in the U.S. and 2036 in the EU [8]. - Anaptys estimates that Sagard will have accrued $250 million in royalties and sales milestones through the end of 2025, with full paydown of $600 million expected between Q2 2027 and Q2 2028 [9]. Group 4: Future Developments - The parties have agreed to an expedited schedule with the Delaware Chancery Court, with a trial anticipated in July 2026 [5]. - Milestone and royalty payment obligations to Anaptys will continue during the legal proceedings [5].