Pfizer Inc. said Tuesday it will cut its U.S. sales force by 20 percent, or 2,200 people, as part of a cost-cutting program to transform the company into a more nimble organization as it struggles with sluggish sales.

The drug company has 11,000 sales representatives, and the cuts will be made by the end of the year, according to company spokesman Paul Fitzhenry. He couldn't say how much the cuts would save the company or if it would take any kind of an earnings charge because of the move.

In October, Pfizer said it would slash costs beyond the program announced last year, designed to cut $4 billion in expenses by 2008.