The US Federal Trade Commission has reached a settlement with Amgen allowing the drugmaker to go ahead with its $27.8 billion acquisition of Ireland-based Horizon Therapeutics, dropping its earlier objections to the deal.
The FTC filed a lawsuit on May 16 in a rare move to block a large pharmaceutical deal.
But it suspended its challenge in late August, enabling the agency to consider whether it should settle the case.
The FTC had opposed the deal because of concerns that Amgen would leverage its drugs to pressure insurance firms and pharmacy benefit managers to give favourable terms for Horizon's two key products - the fast-growing thyroid eye disease treatment Tepezza and gout drug Krystexxa.
Under the settlement, Amgen is prohibited from bundling any of its products with Tepezza or Krystexxa.
It is also not allowed to use any product rebate or contract term to exclude or disadvantage products that would compete with those drugs.
Amgen is also prohibited from acquiring any potential rival treatments to Horizon's drugs without the FTC's approval, since the company could try to neutralise competition through acquisitions, the regulator said in a statement.
Consolidation in the industry has given companies the power to engage in exclusionary practices that can cause prices for essential medications to surge, the FTC added.
"The bundling and exclusionary rebating practices at issue in this matter highlight deeper concerns about how pharmaceutical companies and pharmacy benefit managers may work together to deprive Americans of access to affordable drugs," said Lina Khan, chair of the FTC, in the statement.
The companies expect the deal to close early in the fourth quarter of this year.
