Sulphonylurea Diabetes Drugs May Increase Heart Attack Risk: Study

New research appears to confirm the heart risks associated with a long-established class of diabetes drugs known as sulphonylureas, which includes Diabeta, Glynase and Micronase.  

The study was published online by the medical journal Diabetic Medicine on September 16, seeking to confirm label warnings that have long been on the drugs. The findings indicate that side effects of sulphonylurea diabetes drugs may elevate the risk of heart attack among patients with diabetes.

Researchers conducted a meta-analysis of 33 studies that involved more than 1.3 million patients. They found higher rates of cardiovascular-related hospitalization and death among users of a class of diabetes drugs known as sulphonylurea. The class of drugs are popular for the treatment of type 2 diabetes. The best selling drug in the class, glibenclamide, also known as gylburide, is sold in the U.S. under the brand names of Diabeta, Glynase and Micronase.

Along with metformin, glibenclamide is listed by the World Health Organization Model List of Essential Medicines; the only two diabetes drugs to make that list. Side effects can include hypoglycemia, cholestasis and cholestatic jaundice.

The class of drugs are often used as a second treatment option along with metformin and other drugs. It is also sold in combination with metformin under the brand names Glibomet, Glucovance and Benimet.

Increased heart risks associated with the drugs appear to include heart disease, heart attack, stroke and cardiovascular death.

“This finding warrants consideration in clinical practice when other treatment options may be available,” researchers concluded.

Diabetes Drug Heart Problems

The findings are just the latest health concern over diabetes drugs, which have been rocked by health risk problems in recent years.

In 2009, the FDA required that drug makers establish that all new proposed diabetes medications do not increase the risk of heart side effects. The agency decided to intensify their review of proposed diabetes medications after they were harshly criticized for their handling of the diabetes drug Avandia.

Avandia was once a blockbuster diabetes treatment, but it has virtually disappeared from the marketplace amid concerns about an increased risk of heart attacks and heart disease.

More recently, a number of other serious health concerns have been linked to some of the most widely used diabetes drugs in the country.

Since 2011, sales have fallen for the diabetes drug Actos amid bladder cancer concerns. Hundreds of former users of the medication are now pursuing Actos lawsuits against Takeda Pharmaceuticals alleging that the drug maker failed to adequately research the medication or warn about the risk of cancer.

Over the past year, concerns about a risk of cancer have also been linked to a newer class of diabetes drugs, known as incretin mimetics, which include Byetta, Januvia, Janumet and Victoza, among others. Reports have suggested that side effects of incretin mimetics may increase the risk of pancreatic cancer.

Byetta (exenatide) was the first member of this class approved by the FDA, introduced by Amylin Pharmaceuticals in 2005 as a twice daily injection. Januvia (sitagliptin) was introduced by Merck the following year as an oral medication, and a combination pill containing Januvia and the older diabetes medication metformin was introduced in 2007 under the brand name Janumet. Victoza (liraglutide) was introduced by Novo Nordisk in 2010 as a daily injection.

The medications are widely used among individuals with type 2 diabetes, generating billions in annual sales. Januvia and Janumet are among the best selling medications for the global pharmaceutical company Merck, generating about $4 billion in sales last year. Victoza sales were about $1.8 billion last year for Novo Nordisk and Byetta earned a reported $149 million for Amylin Pharmaceuticals.

In March 2013, the FDA and European drug regulators launched investigations into the potential risk of pancreatic cancer from incretin mimetics after results of a small, independent study found evidence of precancerous cells in the pancreas of users of the drugs. While the FDA has since released a statement indicating that their review of the currently available data has found no evidence of a connection between pancreatic cancer and use of Byetta, Januvia or other incretin mimetics, research is ongoing.