The U.S. Federal Trade Commission will sue to block Amgen’s $28.3 billion acquisition of Horizon Therapeutics, according to a person familiar with the matter.
The lawsuit, scheduled to be filed Tuesday, would mark the FTC’s first attempt to block a drug industry deal in more than a decade.
FTC Chairman Lina Khan is among a new wave of progressive antitrust officials appointed by President Joe Biden to vow to take a tougher line against anticompetitive practices in the United States.
Shares in Ireland-based Horizon fell more than 17% in premarket trading. The news appeared to hit Seagen as well, with the company down 5.6 percent in premarket trading as investors weighed the possibility of the FTC targeting other deals in the industry. The oncology-focused biotech agreed to be acquired by Pfizer in March for $43 billion.
The move was first reported by Bloomberg.
Additional reporting by Peter Wells in New York