Will Actos Replace Avandia As Drug to Watch?

Pittsburgh, PAOnce the US Food and Drug Administration (FDA) decided to severely restrict Avandia's use, prevailing wisdom seemed to be that because Actos side effects were not as severe, patients could easily switch to Actos. What may not have been realized, however, is that there is a risk of Actos side effects, reportedly including a risk of Actos heart failure. Furthermore, the FDA has put Actos on a list of drugs to watch.

Actos and Avandia have long been compared to each other. They are similar enough that they can be compared to each other, but different enough that they do not necessarily have the same side effects. A long-anticipated study, called Thiazolidinedione Intervention with Vitamin D Evaluation (TIDE), was designed to compare the safety of Actos versus the safety of Avandia.

In 2010, the FDA halted that trial, meaning that conclusive evidence showing one drug is safer than the other likely will never be released. According to an article in the CMAJ (Canadian Medical Association Journal; 05/31/2010), critics of the TIDE trial argued it was unethical to knowingly put some trial participants on Avandia (known generically as rosiglitazone) when other patients were put on Actos (known generically as pioglitazone), which was thought to be safer than Avandia.

A study published in the BMJ, conducted by Dr. David Juurlink, reportedly suggested that Actos was associated with heart problems, although to a lesser degree than Avandia.

Meanwhile, the FDA recently included Actos on its list of drugs to watch because of a reported concern about rhabdomyolysis, a condition in which the patient's muscle fibers are released into the bloodstream, potentially causing kidney damage. The FDA notes that it has identified that as a potential safety issue but that it is not a sign that a causal relationship occurs between Actos and rhabdomyolysis.

In September, 2010, the FDA announced it was reviewing data to determine whether Actos is linked to an increased risk of bladder cancer. According to the FDA, findings from studies that involved animals and studies that involved humans suggest a potential link that the FDA believes warrants further examination.

Actos is used to control blood sugar levels in patients with type 2 diabetes mellitus.