Diabetes Drug Actos Under Scrutiny

If you are taking the diabetes drug Actos (pioglitazone), it is not time to panic or discontinue the medication yet.  The Food and Drig Administration (FDA) is reviewing data about the diabetes drug because of concerns it may increase the risk for bladder cancer, but at this time there is no clear evidence that Actos increases the risk of bladder cancer.

Preliminary results from a long-term observational study designed to evaluate the risk of bladder cancer asociated with the use of piogitazone prompted a safety review this diabetes drug. 

Actos manufacturer Takeda Pharmaceuticals North America, Inc., San Diego compiled data based on five years of an ongoing ten year observational study which showed no overall association between Actos exposure and risk of bladder cancer.  However patietns with the longest exposure to Actos and highest cumulative dose of the drug did reveal an increased risk of bladder cancer.

The class of drugs known as peroxisome proliferator-activated receptor (PPAR) agonists, Actos (piogitazone) is used to control blood sugar in patients with type 2 diabetes mellitus.  The only other drug in this class is Avandia (rosiglitazone) which has been surrounded in controversy since FDA advisors issued a mixed verdict about whether it should stay on the marked due to concerns of heart attack risk.

Currently the FDA is deliberating whether to take Avandia off the market or add restrictions and label warnings due to its cardiovascular risks.  Actos has generally been viewed as a safer option for patients with an FDA advisory panel voted 21 to 4 in affirming Actos safer than Avandia.

The first hint of a possible cancer risk materialized in preclinical carcinogenicity studies described in the drug's FDA approved label.  Male rats receiving a dose of Actos that produced blood drug levels equavelant to what a clinical dose would generate were found to have bladder tumors.

In 2 clinical studies, patients receiving Actos experienced a higher rate of bladder cancer than patients taking other agents.

Patients should not stop taking Actos unless told to do so by their health care professional.  If they have concerns about Actos or Avandia, patients should talk to their health care professional.