Drugmaker GlaxoSmithKline said Thursday it will keep several established brand-name products sold in North America and Europe after testing the market to see if they could sold for a sufficient amount of cash.

The "established" products group includes medication that still works and is for sale to patients, but no longer has market exclusivity because patents have expired, and therefore generate less profit than in the past. Examples include the heartburn drugs Tagamet and Zantac, the migraine medicine Imitrex and the antidepressant Paxil.

"The company has evaluated all bids received and has concluded, consistent with its key criteria of maximizing shareholder value, not to pursue divestment of these products," the company said in a statement.

London-based GSK, which has operations in Pennsylvania and New Jersey, has started a three-year restructuring plan to eliminate $1.57 billion in annual costs. The company announced layoffs on Wednesday, with the Philadelphia region gaining some research jobs and losing some in commercial operations.