McKesson is laying off 1,600 employees, or 4% of its U.S. workforce, in the wake of losing some key clients, Bloomberg reported late Wednesday.

The nation’s largest pharmaceutical distributor, McKesson started informing staff about the cuts in the middle of this month after having done a strategic review in January, according to Bloomberg.

Of late, McKesson has been active on the acquisitions front. Early this month, the company unveiled a deal to acquire Rexall Health, one of Canada’s leading drug chains, from Katz Group for $2.2 billion.

And about a week before that, McKesson announced that it was buying Vantage Oncology LLC, a provider of radiation oncology, medical oncology and integrated cancer care, and Biologics Inc., an oncology pharmacy services company, for a combined $1.2 billion.