Pfizer laying off some US sales representatives

(AP) Drugmaker Pfizer Inc. is starting another round of layoffs, targeting U.S. sales representatives who promote Pfizer primary care medicines to doctors.

The New York-based Viagra maker isn't giving details on how many salespeople it employs, how many will leave or when that will happen. Individual salespeople haven't been notified whether they'll be furloughed.

A Pfizer spokesman confirms changes are coming but says details about the sales force are proprietary.

In a statement, the world's biggest drugmaker says it continually evaluates how to be more efficient and best allocate money and staff to serve customers.

Generic competition to popular drugs such as Pfizer's cholesterol blockbuster Lipitor means they're not promoted anymore. But reps are needed to promote a big anticlotting drug awaiting approval and current big sellers like pain treatment Lyrica.