Takeda Pharmaceutical Co.'s Actos diabetes drug may be kept on the market with new warnings, the European Medicines Agency said after reviewing research showing the drug carried a slightly increased risk of bladder cancer.

The benefits of pioglitazone, the active ingredient in Actos and other diabetes treatments, outweigh its risks in a limited group of patients with type 2 diabetes, the London-based agency's Committee for Medicinal Products for Human Use said Thursday in a statement on its website.

"These medicines remain a valid treatment option for certain patients with type 2 diabetes," though there is a small increased risk of bladder cancer, the agency said. The risk can be reduced by "appropriate patient selection and exclusion," including regular reviews of how well the drug is working for individual patients, the agency said.