Amgen intends to issue a massive bond to help finance the $28 billion Horizon Therapeutics acquisition.

According to the company and deal documents, Amgen Inc. started talks with investors on Tuesday about a possible jumbo bond deal to help finance its $28 billion acquisition of Dublin-based Horizon Therapeutics.

In December, Amgen AMGN, +2.69% and Horizon HZNP, +0.28% announced plans for the merger, with Amgen getting a $28.5 billion bridge credit facility from Citibank and Bank of America to assist with the transaction.

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