Side Effects of Actos Linked to Macular Edema: Study

Amid growing concerns about the potential risk of bladder cancer from Actos, a new study indicates that the popular diabetes drug may also increase the risk of macular edema, which could lead to blindness.

Researchers from the University of Nottingham presented a data at the American Diabetes Association’s Annual Meeting in San Diego that suggests side effects of Actos and Avandia, a similar diabetes drug in the same class, may increase the risk of macular edema in diabetics who fail to keep their blood sugar under control.

Use of Avandia has already greatly diminished in recent years due to concerns about an increased risk of heart attacks and death associated with the drug. However, Actos remains a popular treatment alternative for diabetics, although concerns have recently surfaced about a possible increased risk of bladder cancer associated with the drug.

Earlier this month, an Actos recall was issued in France and Germany after studies showed that the medication may increase the risk of bladder cancer. However, the drug remains widely used in the United States, where the FDA has issued an Actos bladder cancer warning and is continuing to review the safety of the drug.

The new study that finds a potential risk of macular edema from Actos and Avandia looked at data involving more than 100,000 diabetics in the U.K. Researchers divided the diabetics into those had taken Actos or Avandia and those who had not, and found that 1.3% of those who took one of the diabetes drugs developed diabetic macular edema after one year, compared to 0.2% of those who did not take either of the drugs.

Researchers determined that the risk of diabetic macular edema increased 3 to 6 times among people who used Actos or Avandia.

Actos (pioglitazone) was approved by FDA to treat Type 2 Diabetes in July, 1999. It is Takeda Pharmaceuticals’ best-selling drug, with sales of $3.4 billion last year.

Avandia (rosiglitazone) was first introduced in 1998 to treat type 2 diabetes by helping control blood sugar levels. The drug was used by millions of diabetics throughout the world, before sales began to plummet in mid-2007, after a study published by the New England Journal of Medicine highlighted the potential Avandia heart risks.

Severe restrictions on Avandia use have been put in place in the United States, making the medication available in only select pharmacies by mail order and requiring special educational programs before the drug can be prescribed.

Thousands of Avandia lawsuits have been filed against GlaxoSmithKline over their failure to warn about the potential risk of heart problems from Avandia. Recently, momentum for potential Actos lawsuits has been growing as evidence has established a potential increased risk of bladder cancer, which it appears Takeda Pharmaceuticals may not have adequately researched or warned about.