TRENTON, N.J. -- Struggling Anglo-Swedish drugmaker AstraZeneca PLC said Monday that it will eliminate 1,600 jobs, mostly in the U.S. and United Kingdom, as its new CEO starts a major research and development reorganization.

The cuts, meant to reduce costs and make research programs more productive, come just weeks after the company reported big drops in revenue and net income for 2012 and forecast continuing difficulties as generic competition hurts sales.

The job reductions amount to nearly 3 percent of AstraZeneca's 57,200 workers worldwide and are part of moves affecting several major AstraZeneca sites in the UK, US and Sweden.

The changes, to be made between now and 2016, are expected to produce annual savings of about $190 million by then. They'll result in restructuring charges of $1.4 billion, about $800 million of that likely in cash.

In the U.S., AstraZeneca will scale back its site in Wilmington, Del., by about 1,200 jobs. That includes eliminating 650 positions and shifting 300 others as key functions are transferred to Gaithersburg, Md., home to AstraZeneca's MedImmune subsidiary.

Wilmington will still be AstraZeneca's North American headquarters for sales and marketing, with about 2,000 employees remaining. The other 250 jobs being cut in Wilmington include 80 going to a site in Waltham, Mass., and about 170 going to other U.S. or overseas locations.