Bristol Myers sues Amgen over proposed Opdivo biosimilar

Bristol Myers and Ono, which co-developed Opdivo, allege that Amgen's biosimilar would infringe seven U.S. patents covering the drug, and asked the court to block sales of the biosimilar while their patents remain in force.

Opdivo has been approved in the U.S. to treat advanced or metastatic cancers, including melanoma, non-small cell lung cancer and kidney cancer.

Bristol Myers and Ono settled a patent dispute with Merck in 2017 over its rival blockbuster cancer drug Keytruda. Under the settlement, Merck agreed to pay $625 million and a share of Keytruda royalties through 2023.

Bristol Myers said in a report filed with the U.S. Securities and Exchange Commission in February that it expects to maintain patent exclusivity over Opdivo until 2028.

Bristol Myers Squibb BMY.N and Ono Pharmaceutical 4528.T have sued Amgen AMGN.O in Delaware federal court, seeking to block Amgen's proposed U.S. biosimilar of their blockbuster cancer immunotherapy drug Opdivo.

• The lawsuit, filed last week and made public on Monday, alleges that Amgen's biosimilar would infringe several patents.
• Opdivo earned Bristol Myers more than $5.9 billion in revenue in the United States last year, according to a company report.
• An Amgen spokesperson on Tuesday declined to comment on the lawsuit but said the company has applied for U.S. Food and Drug Administration approval of its drug and "remains confident" that it will be "in the first wave of Opdivo biosimilars."
• Spokespeople for Bristol Myers and Ono did not immediately respond to requests for comment.