02:18 PM EDT, 10/30/2025 (MT Newswires) -- Pfizer ( PFE ) is readying to sue Metsera ( MTSR ) and potentially Novo Nordisk ( NVO ) after the Danish company submitted an unsolicited proposal to acquire Metsera ( MTSR ), outbidding Pfizer ( PFE ), Semafor reported Thursday, citing a person close to the matter.

Pfizer ( PFE ) said earlier Thursday that Novo's bid does not qualify as a "superior company proposal" relative to its agreement with Metsera ( MTSR ). Pfizer ( PFE ) said Novo Nordisk ( NVO ) is attempting to "suppress competition in violation of law," and that the proposal is "structured in a way to circumvent antitrust laws."

Pfizer ( PFE ), Metsera ( MTSR ), and Novo Nordisk ( NVO ) didn't immediately reply to MT Newswires' requests for comments.

Metsera ( MTSR ) shares were up 26% while Pfizer ( PFE ) was edging 0.2% higher and Novo Nordisk ( NVO ) was down 2.1% in recent afternoon trading.

(Market Chatter news is derived from conversations with market professionals globally. This information is believed to be from reliable sources but may include rumor and speculation. Accuracy is not guaranteed.)

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