In early 2014, the FDA warned about study results that suggested the type 2 diabetes drug Onglyza could be linked to the risk of heart failure. In April 2015, the FDA scheduled an advisory panel meeting of the Endocrinologic and Metabolic Drugs Advisory Committee to further examine the potential risks of this and other similar drugs. The panel recommended that Onglyza and other similar drugs should carry warnings about their potential to increase the risk of heart failure.
Now, a new study review published in the British Medical Journal (BMJ), raises additional concerns with Onglyza and similar types of diabetes drugs. Researchers have discovered that when these drugs are combined with “sulphonylureas,” another class of antidiabetic drugs, they increase risk of hypoglycemia, or low blood sugar, a potentially life-threatening condition.
The Danger of Hypoglycemia in Older Adults with Diabetes
According to this study, hypoglycemia has emerged as a leading complication of diabetes in adults 60 years and older who have a long history of the disease. It’s the second leading cause of admission to the hospital in people with type 2 diabetes, which accounts for 20-25 percent of hospital admissions for adverse drugs reactions, and can precipitate heart failure. It has also been associated with an increased risk of falls and fractures.
Hypoglycemia occurs when the blood sugar levels drop too low, usually less than 70 mg/dl. The condition may also be called “insulin reaction” or “insulin shock,” and can produce shakiness, sweating, chills, confusion, rapid heartbeat, lightheadedness, blurred vision, weakness, and even seizures and unconsciousness.
Drugs like Onglyza, which are called dipeptidyl peptidase-4 (DPP-4) inhibitors, are indicated as a second line treatment in people who have type 2 diabetes and aren’t able to control their blood sugar levels with one medication alone. These are newer drugs that stimulate the pancreas to create more insulin after a meal, so the body can better metabolize the glucose and keep blood sugar levels steady.
When Onglyza, Januvia, and other DPP-4 inhibitors are used alone, the incidence of hypoglycemia is comparable to that of a placebo or to metformin, the standard diabetes drug. The DPP-4 inhibitors have also been found to create no increased risk when combined with metformin or “thiazolidinediones,” another class of antidiabetic drugs.
But when combined with sulphonylureas, the results were quite different.
Combining Onglyza with Other Diabetes Drugs Can be Dangerous
Researchers reviewed data from 10 studies representing 6,546 participants. A total of 4,020 of these were taking DPP-4 inhibitors like Onglyza along with sulphonylureas, and 2,526 were taking a placebo plus sulphonylureas.
Results showed that adding DPP-4 inhibitors to sulphonylurea to treat those with type 2 diabetes was associated with a 50 percent increased risk for hypoglycemia. The researchers warned that doctors need to “respect recommendations for a decrease in sulphonylureas dose when initiating DPP-4 inhibitors.”
These results come just as the FDA released a new announcement in April 2016 that it was requiring manufacturers of DPP-4 inhibitors to add new warnings to their drug labels concerning the risk of heart failure.