Patients taking a class of medications used to treat type 2 diabetes are far more likely to develop bladder cancer than patients on other types of diabetes drugs, according to a new British study.
The study pitted glitazones against sulfonylurea agents, both medications used to treat type 2 diabetes. Glitazones, or thiazolidinediones, work by controlling blood sugar by improving insulin sensitivity. Glitazones on the market today include the popular diabetes treatments pioglitazone (Actos) and rosiglitazone (Avandia).
Sulfonylurea agents are in a class known as anti-diabetic agents, and work by helping the pancreas produce more insulin. Sulfonylurea agents include the drug glipizide (Glucotrol).
In 2010, the Food and Drug Administration (FDA) severely restricted the blockbuster drug Avandia after it was linked to fatal heart attacks. Actos was seen as a safer alternative until the FDA issued a warning that new studies showed the drug may put users at risk for bladder cancer. The risk was greater among people who used the drug for at least a year.
The British study, which involved data from 60,000 patients, found patients on glitazones – whether Avandia or Actos – for five years had a 72 percent relative increased risk of developing bladder cancer. The analysis indicated that Actos was just as likely to cause the disease as Avandia.
The first drug in the glitazone class, troglitazone (Rezulin) was removed from the United States in 2000 after three years because it caused liver toxicity.
Source: University of Pennsylvania