The U.S. Federal Trade Commission (FTC) has temporarily halted its challenge regarding Amgen's (AMGN:US) acquisition of Horizon Therapeutics (HZNP:US).

Two companies agreed on a deal in December 2022 that would see Amgen take control of Horizon in exchange for $27.8 billion.

Horizon shares rose about 6% on the news.

This suspension, which will remain in effect until September 18, enables the FTC and Amgen to work on a settlement. Amgen has acknowledged this development and is ready to present its case, asserting that there are no legal or factual grounds to impede the acquisition.

“We would be pleased if our commitment were honored instead of going through a lengthy court process," the company said in a statement, according to Reuters.

The FTC initiated legal action on May 16 with the aim of blocking the transaction.

The agency's opposition to the deal was based on concerns that Amgen might employ its significant sales of drugs as leverage to influence insurance companies and pharmacy benefit managers into providing favorable terms for Horizon's two key products: Tepezza and Krystexxa.

“The acquisition of Horizon is a compelling opportunity for Amgen and one that is consistent with our strategy of delivering long-term growth by providing innovative medicines that address the needs of patients who suffer from serious diseases,” Robert A. Bradway, chairman and chief executive officer of Amgen said when the deal was announced.

Congressman Daniel Goldman sold $15,000 - $50,000 on HZNP shares on January 31, when they closed at $109.72.

The stock is seen trading around $113 apiece on Monday.