University of Iowa Hospital and Clinics is recruiting volunteers to participate in a study to compare the long-term benefits and risks of four widely used diabetes drugs in combination with metformin, the most common first-line medication for treating type 2 diabetes. Beginning recruitment in June, the project is called the Glycemia Reduction Approaches in Diabetes: A Comparative Effectiveness (GRADE) Study.

If metformin is not enough to help manage type 2 diabetes, a person’s doctor may add one of several other drugs to lower glucose (blood sugar). But while short-term studies have shown the efficacy of different drugs when used with metformin, there have been no long-term studies of which combination works best and has fewer side effects.

“Type 2 diabetes progresses slowly, over a long period of time,” said Barbara Linder, M.D., Ph.D., the GRADE project officer at the National Institute of Diabetes and Digestive and Kidney Diseases, part of the National Institutes of Health (NIH). “This study will help us understand how different combinations of medications affect the disease over time, and ultimately help physicians make better choices for their patients’ long-term care.”

The study will compare drug effects on glucose levels, adverse effects, diabetes complications, and quality of life over an average of nearly five years.

GRADE aims to enroll about 5,000 patients. Investigators at UI Hospital and Clinics and 36 other study sites are seeking people diagnosed with type 2 diabetes within the last five years. Eligible participants may be on metformin, but not on any other diabetes medication. During the study, all participants will take metformin along with a second medication randomly assigned from among four classes of medications, all approved for use with metformin by the U.S. Food and Drug Administration.

Three of the classes of medications increase insulin levels. They are: sulfonylurea, which increases insulin levels directly; DPP-4 inhibitor, which indirectly increases insulin levels by increasing the effect of a naturally occurring intestinal hormone; and GLP-1 agonist, which increases the amount of insulin released in response to nutrients. The fourth type of medication is a long-acting insulin.

Participants will have their diabetes medications managed free of charge through the study, including at least four medical visits per year, but will receive other health care through their own providers.

“GRADE differs from any prior research in that it will perform a head-to-head comprehensive comparison of the most commonly used drugs for diabetes over a long period of time,” says William Sivitz, M.D., UI endocrinologist and professor of internal medicine who is principal investigator at the UI site. "The GRADE study will not only determine which medications most effectively control blood glucose levels, but also determine individual patient characteristics that are associated with a better or worse response to the different medications. This should provide understanding of how to personalize the treatment of diabetes.”

David M. Nathan, M.D., of Massachusetts General Hospital, Boston, and John Lachin, Sc.D., of The George Washington University, Washington, D.C., are the national co-principal investigators.

GRADE (ClinicalTrials.gov number: NCT01794143) is supported under NIH grant U01DK098246. Additional support in the form of donation of supplies comes from the National Diabetes Education Program, Sanofi-Aventis, Bristol-Myers Squibb, Novo Nordisk, Merck, BD Medical, and Roche Diagnostics.

For information about participating in the study at UI Hospitals and Clinics, contact Tamara Lowe at 319-384-8103 or Jennifer McConnell at 319-356-7506

Learn more about the study at grade.bsc.gwu.edu.