FDA Warns that Actos may Increase Bladder Cancer Risk

Pioglitazone (marketed as Actos, a diabetes drug from Takeda Pharmaceutical Company Limited) has been found to increase the risk of bladder cancer if used for more than one year, according to U.S. drug regulators.

The U.S. Food and Drug Administration (FDA) reported on Wednesday, June 15^th that the drug Actos will bear a warning label stating this information after preliminary five-year results of an ongoing ten-year study were reviewed, according to the Endocrine Society.

This move took place after France suspended Actos and other drugs containing pioglitazone on the basis of a French database study run by Caisse Nationale d'Assurance Maladie des Travailleurs Salari(CNAMTS)—in English, the French National Health Insurance Agency for Wage Earners. This study was performedindependently by French authorities.

According to the FDA, the U.S. study showed that participants who endured the greatest exposure to pioglitazone—as well as patients receiving the highest cumulative dose of the drug— suffered an increased risk of bladder cancer, although pioglitazone did not lead to an increased risk of bladder cancer in the study overall.

There was a 40% increase observed in disease among patients administered pioglitazone for more than twelve months. After more than twenty-four months of pioglitazone, an individual’s risk increased to 95%; based on this information, the FDA estimated that treatment for more than twelve months was associated with 27.5 excess cases of bladder cancer per 100,000 person-years follow-up vs. never use of pioglitazone.

The European Medicines Agency acknowledged in a statement released on June 9, 2011 that the “review of pioglitazone is ongoing,” but “the Committee for Medicinal Products for Human Use is not recommending any changes to the use of pioglitazone-containing medicines.”

Actos is used typically to treat type 2 diabetes. According to the FDA, it is estimated that 2.3 million patients filled a prescription for a product containing pioglitazone from January to October 2010.

The FDA recommended health care providers not to give pioglitazone to patients with active bladder cancer. They also recommended that physicians use the drug with caution in patients who have a history of bladder cancer; personal judgment, they concluded, should be used when weighing the benefits of controlling a patient’s blood sugar using pioglitazone against the potential risks of cancer recurrence.

Data from both the ongoing U.S. epidemiological study and the French study will be evaluated, said the FDA.