GSK and TESARO continue to defend rights to Jemperli (dostarlimab) as a dispute with AnaptysBio over a 2014 licence agreement remains unresolved.
Written By: Pharmacally Medical News Desk
GSK plc and its oncology subsidiary TESARO, Inc. are continuing to defend their rights to Jemperli (dostarlimab), following a procedural ruling in an ongoing licensing dispute with AnaptysBio, Inc..
Jemperli, a PD-1 inhibitor, is approved in more than 35 countries for certain forms of endometrial cancer and remains a growing component of GSK’s oncology portfolio. Its clinical development programme is expanding into additional tumour types, including rectal, colorectal, and head and neck cancers.
The dispute centres on control of the cancer therapy Jemperli (dostarlimab). AnaptysBio, Inc. originally granted TESARO, Inc. the rights to develop and commercialise the drug under a 2014 agreement. TESARO, now part of GSK plc, has since advanced the therapy and brought it to multiple global markets.
AnaptysBio has alleged that TESARO did not meet certain conditions of that agreement and has indicated plans to revoke the licence. Such a move would directly affect control over the ongoing development and commercialisation of Jemperli. TESARO and GSK dispute these claims and are seeking to maintain their rights to the therapy.
In a recent development, the Delaware Court of Chancery granted AnaptysBio’s motion to dismiss TESARO’s claim for anticipatory breach. The key question of whether TESARO retains full rights to Jemperli remains unresolved, and the disagreement between the companies is ongoing.
Despite the litigation, Jemperli’s development and commercialization continue. Growth has been supported by regulatory expansions in endometrial cancer across the United States and European Union, alongside an ongoing clinical programme evaluating its potential use in multiple solid tumours.
The outcome of the case may influence future rights associated with Jemperli, but the central contractual issues remain unresolved as proceedings continue.
Despite the ongoing dispute, Jemperli continues to gain traction in oncology markets. GSK plc has reported growth driven by expanded use in endometrial cancer, particularly following regulatory label updates in the United States and European Union. The therapy remains a key component of GSK’s oncology portfolio, with uptake supported by its positioning in biomarker-defined patient populations.
Clinical development of Jemperli is ongoing across multiple tumour types. Beyond endometrial cancer, studies are evaluating its potential in rectal, colorectal, and head and neck cancers, including use in earlier lines of therapy and in combination regimens. This broad development programme reflects continued interest in expanding the role of PD-1 inhibitors across solid tumours.
Reference
TESARO, a GSK subsidiary, provides update on AnaptysBio, Inc. litigation | GSK