AstraZeneca has announced plans to cut about 400 employees in its U.S. commercial operations, citing a need to reduce costs. The company said the jobs are mainly at its U.S. headquarters in Wilmington, Del., and some field-based, non-sales roles. The company has about 14,400 employees in North America. About 70 of the estimated positions to be eliminated will come from existing vacancies, leaving about 330 current workers affected by the cuts, said spokesman Tony Jewell. The specific jobs targeted haven't been identified yet. All decisions will be finalized by early December.

"The changes will enable the company to compete in a challenging environment, including pricing pressures and the continuing growth of generics medicines," the company said in a press release.

Several of AstraZeneca's best-selling drugs face the loss of patent expiration in coming years.