Viatris, a global pharmaceutical company formed by the merger of the Upjohn division of Pfizer and Mylan, said it would begin a restructuring program to save $1 billion immediately after the company's launch.

Observers said Viatris’s downsizing plan might affect workers in the Korean offshoot.

On Monday, Pfizer said it had completed the deal from Viatris by spinning off the Upjohn business and combine it with Mylan. According to Pfizer, Pfizer shareholders own 57 percent of Viatris common stock, and Mylan shareholders, 43 percent. Viatris began trading on Tuesday.

Announcing its official launch on Monday, Viatris said it would start a restructuring program to save $1 billion.

According to Pittsburgh Business Times, Viatris is headquartered in the U.S. and will retain its Canonsburg facility as one of its three global centers. The other two are in Shanghai, China, and Hyderabad, India. Viatris has a large manufacturing plant and R&D center in Morgantown, W.V. The company has 45,000 employees around the world but plans to execute a restructuring program to cut costs by $1 billion, it said.

“The company is currently in the process of defining the specific parameters of the program, including workforce actions and other restructuring activities,” Viatris said in a statement. “Further details for this program are expected to be disclosed by the end of this year as plans are finalized.”

With the Viatris global headquarters’ announcement of a restructuring plan, the Korean branch will not be free from its impact, industry watchers said.

As Mylan has no Korean unit, former Pfizer Upjohn’s leader Lee Hye-young will become CEO of Viatris Korea.

Pfizer Upjohn has steady selling drugs such as hyperlipidemia treatment Lipitor (ingredient: atorvastatin), hypertension drug Norvasc (amlodipine), and nonsteroidal anti-inflammatory drug Celebrex (celecoxib).