Liraglutide and insulin most effective in maintaining optimal blood sugar levels in diabetics: Study

Results of GRADE demonstrated that liraglutide and insulin were the most effective of the four medications in keeping A1C levels less than 7%. 

USA: Liraglutide and insulin are more effective than other common diabetes in maintaining average blood sugar levels, according to findings from GRADE Study.

The study is the largest and longest study comparing the effectiveness of common medications to treat type 2 diabetes. The comparison included two oral medications, the sulfonylurea glimepiride, and the DPP-4 inhibitor sitagliptin, and two injectable medications, insulin glargine and the GLP-1 receptor agonist liraglutide. This head-to-head comparison of glucose-lowering medications will help inform individualized treatment strategies

The findings of the study were presented at the virtual 81st Scientific Sessions of the American Diabetes Association (ADA). 

Controlling blood glucose levels over time is a major challenge for people with type 2 diabetes, a condition that disproportionally impacts Black and Hispanic people, who are 50% more likely to have diabetes than non-Hispanic white people. The GRADE study included a highly diverse population of 20% Black and 18% Latino patients. It was designed to compare the effectiveness of glucose-lowering medications in maintaining average blood glucose levels in the target range that has been identified to reduce the risk of long-term complications.

GRADE performed a head-to-head comparison of the four most commonly used classes of medications used in conjunction with metformin and looked at their ability to keep average blood glucose levels in the recommended target range, as indicated by an A1C level (a measurement of average blood glucose) of less than 7%. Medications in addition to metformin, which is recommended by the ADA for initial use to treat type 2 diabetes, are often needed to treat type 2 diabetes to help lower A1C levels. The comparison included two oral medications, the sulfonylurea glimepiride and the DPP-4 inhibitor sitagliptin, and two injectable medications, insulin glargine and the GLP-1 receptor agonist liraglutide. The effects of each of the four medications on diabetes complications and side effects were also examined.

The study enrolled more than 5,000 patients with type 2 diabetes with an average age of 57 years and an average duration of diabetes of four years. Approximately 1,250 were randomly assigned to each of the four medications. GRADE was conducted for an average of five years and a maximum of more than seven years.

Results of GRADE demonstrated that liraglutide and insulin were the most effective of the four medications in keeping A1C levels less than 7%. Glimepiride had a smaller effect and sitagliptin showed the lowest effect, resulting in the highest frequency of developing A1C levels greater than 7%. Insulin glargine was most effective in keeping A1C levels less than 7.5%, a secondary outcome of the study. The results were similar among men and women and across the different races and ethnicities and age groups. 

"The ultimate goal of GRADE is to help clinicians select the therapies that will work best for individual patients, as diabetes care is not a one-size-fits all approach," said David M. Nathan, MD, Director, Diabetes Center, Massachusetts General Hospital, Professor of Medicine, Harvard Medical School, Boston, MA and lead study chair. "We believe these results will provide value to both patients and their providers when deciding which medication is needed to meet their appropriate blood glucose target and we are encouraged that these findings can be applied to a very diverse range of patients."

"Comparative effectiveness trials like GRADE are essential in helping people make decisions about how to best manage and treat chronic diseases like type 2 diabetes," said Dr. Henry Burch, NIDDK project scientist for the study. "NIH supports GRADE and studies like it to help people with type 2 diabetes make informed choices between medications based on individual patient needs and the characteristics of the medications."

The authors state that future analyses of the results from the highly diverse GRADE participants will help personalize the use of glucose-lowering medications in type 2 diabetes.