The drugs metformin and glyburide are commonly used by people with type 2 diabetes to control blood glucose levels. Individually the agents may or may not be effective, but together they pack a one-two punch. A new combination of metformin and glyburide in a single tablet (250 mg metformin and 1.25 mg glyburide), manufactured by Bristol-Myers Squibb under the trade name Glucovance, helped people with type 2 diabetes achieve greater blood sugar control than either pill alone, reported investigators at the 60th annual meeting of the American Diabetes Association in June 2000. Glucovance is currently under review by the FDA.
A total of 806 people with type 2 diabetes age 60 and older took part in the clinical trials. Patients received either placebo, 2.5 mg glyburide, 500 mg metformin, 250 mg/1.25 mg metformin/glyburide or 500 mg/2.5 mg metformin/glyburide, and were followed for 20 weeks. At the end of the study period, 66 percent of the 250 mg/1.25 mg metformin/glyburide group and 72 percent of the 500 mg/2.5 mg metformin/glyburide group achieved HbA1C levels of less than or equal to seven percent — a measure of adequate blood sugar control — compared to 20 percent of patients taking placebo, 60 percent of those on glyburide alone and 50 percent of those taking metformin alone. Patients taking a metformin/glyburide combination also experienced better control of blood glucose and insulin levels both before and after eating.
“It is quite possible that the results of this study may lead to a new treatment paradigm for patients with type 2 diabetes,” said Dr. Daniel Donovan, assistant clinical professor of medicine, College of Physicians & Surgeons, Columbia University, and one of the study investigators. “None of the currently available oral antidiabetic drugs can, by themselves, address both of the major causes of type 2 diabetes: insulin resistance and insulin deficiency. The results of this study are encouraging because they demonstrate that by prescribing this novel oral antidiabetic, which attacks both major defects of type 2 diabetes, we can help our patients to aggressively control their blood sugar and, most importantly, avoid potentially serious complications.”
Side effects related to Glucovance were minor and included diarrhea, nausea, upset stomach and hypoglycemia.