Buyout on Horizon: Amgen floats $28B offer for rare disease drug maker as Sanofi exits bidding war

It’s official: Just weeks after rare disease drug maker Horizon Therapeutics revealed it was at the heart of a bidding war between Amgen, Johnson & Johnson and Sanofi, Big Biotech Amgen has emerged with a multibillion-dollar M&A victory.

Amgen is offering around $28 billion in cash for its proposed takeover of Horizon, the company said Monday. The drugmaker is paying a premium of approximately $47.9% on the closing share price of $78.76 per Horizon share on Nov. 29, 2022, the company said in its release.

The deal is expected to close in the first half of 2023, Amgen executives said on a conference call Monday morning.  

Meanwhile, Sanofi on Sunday said it was “no longer in discussions with Horizon and it does not intend to make an offer for Horizon.” The French drugmaker explained that the “transaction price expectations do not meet our value creation criteria.”

For its part, J&J said it had exited the deal talks in early December.

After those two large biopharma companies called off their pursuit of Horizon, Amgen was left to claim the prize.

“We’ve admired Horizon’s success for some time,” Amgen CEO Robert Bradway told investors Monday, adding that his company was “prepared to move quickly” on Horizon when the opportunity for a buyout presented itself.

“Horizon’s products are complimentary to Amgen’s portfolio,” the CEO added, noting the deal “builds on Amgen’s success in rare diseases and provides a strong platform for us to expand in this space in the future.”

To finance the deal, Amgen has entered into a bridge credit agreement with Citibank and Bank of America for $28.5 billion.

With the deal, Amgen gets its hands on thyroid eye disease drug Tepezza, chronic gout treatment Krystexxa and Uplizna, a relatively new therapy that treats neuromyelitis optica spectrum disorder.

Together, Horizon's triumvirate of commercial medicines generated $2 billion in sales through the first nine months of the year, Bradway pointed out.

“Each has been delivering strong, volume-driven growth, and each is still early in its lifecycle,” Bradway said. “This allows shareholders of Amgen an opportunity to participate in the long-term growth of these products, while also allowing Amgen to shape the additional lifecycle development opportunities for these important brands.”

Year-to-date, Tepezza has grown sales 37% through the third quarter of 2022, Amgen execs said. Over that same period, Krystexxa increased revenue 27% while Uplizna has brought home $113 million so far, a 148% year-over-year jump.

Aside from Horizon’s approved drugs, Amgen’s head of R&D David Reese highlighted promising prospects in the company’s pipeline such as dazodalibep, daxdilimab and the autoimmune contender HZN-1116.

“Amgen has the scale, expertise and resources to advance [Horizon’s] pipeline molecules with speed and to support global registration and commercialization given the company’s focus on biologics,” Reese said.

Amgen expects to see a return on the deal from 2024. 

The Horizon buyout becomes the largest M&A deal in biopharma in 2022. Similar to last year, this year's largest deal has come in the waning weeks of the year.

Editor's note: This story has been updated with details from an Amgen investor call.