Researchers have found that a new extended-release formulation of metformin can be safely taken only once a day for type 2 diabetes as opposed to the traditional twice a day dosage of immediate-release metformin.
The new drug, which is marketed under the brand name Glumetza, appears to improve the patient's tolerance for higher doses of the drug, according to Dr. Bret Berner, chief scientific officer and vice president of product development at Menlo Park, California-based Depomed, the maker of the drug. To test the efficacy of this formulation around 700 patients with type 2 diabetes were assigned to receive one of three doses of extended-release metformin or immediate-release metformin twice daily for a period of 24 weeks. It was found midway through the study that mean levels of HbA1c (a blood test for long-term glucose control) had come down significantly in all groups. The report published in the medical journal Diabetes Care says that the levels dropped more rapidly in patients who received 2000 milligrams of metformin in a single dose. "With this extended-release formula, you can give the patients up to 2000 mg a day," Berner said. He added that the adverse effects were the same for all the treatment groups, which appears to indicate that even higher doses of metformin are well tolerated by most patients.