Pfizer sues Metsera over $8.5 billion obesity drug bid
Pfizer has taken Metsera and Novo Nordisk to court, claiming Metsera broke their merger agreement by calling Novo's bigger $8.5 billion offer superior to Pfizer's $7.3 billion bid for a US obesity drug developer.
Filed on October 31, 2025, the lawsuit aims to stop Metsera from backing out and wants the planned shareholder vote on November 13 to go ahead.
Legal tussle highlights potential in obesity treatment market
At the heart of this legal fight is control over Metsera's promising obesity drug pipeline—a market expected to explode in coming years.
Pfizer had already cleared early antitrust checks for its buyout plan.
Now, it alleges that Novo and Metsera secretly coordinated before Novo raised its bid, which could break deal rules.
Both companies deny any secret teamwork.
The case also raises questions about fair play in pharma deals and how regulators keep things in check when billions are on the line.