09:24 AM EST, 11/03/2025 (MT Newswires) -- Pfizer ( PFE ) said Monday that it has filed a second lawsuit against Metsera ( MTSR ) , its controlling shareholders, and Novo Nordisk ( NVO ) , claiming that the Danish pharmaceutical giant's proposed acquisition of Metsera ( MTSR ) is anticompetitive.

The lawsuit, which was filed in the US District Court for the District of Delaware, alleges that the proposed deal violates US antitrust laws, such as the Sherman Act and the Clayton Act.

"It constitutes an anticompetitive conspiracy between Novo Nordisk ( NVO ) and Metsera ( MTSR ) in restraint of trade," the company said.

Pfizer ( PFE ) said the acquisition is intended to protect Novo Nordisk's ( NVO ) dominant position in the GLP-1 drug market, and alleges that Metsera's ( MTSR ) controlling shareholders "have conspired with Metsera ( MTSR ) and Novo Nordisk ( NVO ) in furtherance of these anticompetitive activities."

Pfizer ( PFE ) said it will seek "all appropriate remedies," including "injunctive relief to ensure that Novo Nordisk's ( NVO ) anticompetitive proposed transaction is not permitted to move forward."