GSK PLC’s (LSE:GSK, NYSE:GSK)<\/a>\u00a0oncology subsidiary TESARO has secured a partial legal victory after a Delaware court dismissed a counterclaim brought by AnaptysBio, the US biotechnology company, in a dispute over the licence for cancer drug dostarlimab.<\/p>\nThe Delaware Chancery Court granted TESARO’s motion to dismiss AnaptysBio’s claim for anticipatory breach, though the ruling does not address the core contractual dispute between the parties.<\/p>\n
TESARO’s remaining claim for declaratory judgment, which seeks a formal court ruling on the parties’ legal rights under the licence agreement, is unaffected and will proceed to trial.<\/p>\n
The litigation stems from allegations by AnaptysBio that TESARO failed to fulfil certain requirements under a licence agreement signed in March 2014, with AnaptysBio threatening to revoke TESARO’s licence for the drug.<\/p>\n
GSK and TESARO have rejected those allegations as entirely without merit.<\/p>\n
Dostarlimab, sold under the brand name Jemperli, is approved in more than 35 countries for the treatment of certain endometrial cancers, the most common gynaecologic cancer in the United States.<\/p>\n
GSK has reported strong growth for Jemperli following label expansions in endometrial cancer across the US and European Union.<\/p>\n
The company is running clinical trials to assess whether dostarlimab could be used to treat additional cancer types, including rectal, colon, and head and neck cancers.<\/p>\n","protected":false},"excerpt":{"rendered":"GSK unit wins partial dismissal in dostarlimab licence dispute with AnaptysBio Proactive uses images sourced from Shutterstock GSK…\n","protected":false},"author":2,"featured_media":42113,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":"","_share_on_mastodon":"0"},"categories":[20784],"tags":[21241,21242,21237,21236,21240,20785,21239,21238],"class_list":["post-42112","post","type-post","status-publish","format-standard","has-post-thumbnail","category-gsk","tag-anaptysbio","tag-anticipatory-breach","tag-contractual-dispute","tag-delaware-chancery-court","tag-dostarlimab","tag-gsk","tag-licence-agreement","tag-tesaro"],"share_on_mastodon":{"url":"https:\/\/pubeurope.com\/@UnitedKingdom\/116608059641381637","error":""},"_links":{"self":[{"href":"https:\/\/www.europesays.com\/britain\/wp-json\/wp\/v2\/posts\/42112","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.europesays.com\/britain\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.europesays.com\/britain\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/britain\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/britain\/wp-json\/wp\/v2\/comments?post=42112"}],"version-history":[{"count":0,"href":"https:\/\/www.europesays.com\/britain\/wp-json\/wp\/v2\/posts\/42112\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/britain\/wp-json\/wp\/v2\/media\/42113"}],"wp:attachment":[{"href":"https:\/\/www.europesays.com\/britain\/wp-json\/wp\/v2\/media?parent=42112"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.europesays.com\/britain\/wp-json\/wp\/v2\/categories?post=42112"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.europesays.com\/britain\/wp-json\/wp\/v2\/tags?post=42112"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
![\"GSK](\"https:\/\/www.europesays.com\/britain\/wp-content\/uploads\/2026\/05\/cdf753ca3055cef78a0be90a33de0ed8.jpeg\")
GSK unit wins partial dismissal in dostarlimab licence dispute with AnaptysBio Proactive uses images sourced from Shutterstock <\/p>\n