It has been the standard therapy for newly diagnosed type 2 patients, and even for those with prediabetes, to prescribe metformin since it became available over 25 years ago. Before 1995 metformin and sulfonylureas were the only oral treatments for T2D for more than 50 years.

A recent clinical trial called DURATION-8 investigated a combination of two newer drugs, exenatide and dapagliflozin, in patients whose blood glucose levels did not respond to metformin. The results suggest that the combination was safe and continued to be more effective than either drug alone. In addition to stabilizing blood glucose levels, the drug combination was associated with lower blood pressure and body weight. The researchers report that the drug duo remained safe and effective two years (104 weeks) after treatment began.

After adjustments for other possible contributing factors, those who received both drugs saw the most significant average reduction in their glycated hemoglobin (HbA1c) levels. Many therapies in diabetes management are short-lived, which is why this combination should be considered.

The researchers randomly assigned 695 adults with type 2 diabetes whose blood glucose was not adequately controlled by metformin to three treatment groups:

In patients who took both drugs, there were also improvements in blood glucose levels after fasting and 2 hours after eating and reduced body weight and systolic blood pressure. There were no episodes of significant hypoglycemia and a few episodes of minor hypoglycemia. The authors conclude that the clinical benefits of taking both drugs were maintained for two years, with “no unexpected safety findings.”

Diabetes Care, Aug 2020