June 16th, 2011
FDA Says Pioglitazone Use Is Linked to Bladder Cancer
Larry Husten, PHD
The FDA has issued a safety announcement stating that the use of pioglitazone (Actos) for more than 1 year may be associated with increased risk for bladder cancer. The FDA announcement follows last week’s suspension of the drug in France and Germany by regulatory authorities in those countries.
The FDA said that pioglitazone should not be used in patients with active bladder cancer and should be used “with caution” in patients with a history of bladder cancer.
The FDA announcement was based on an ongoing safety review utilizing interim 5-year data from an ongoing epidemiological study. Although no overall increase in bladder cancer was found in the analysis, an increase in bladder cancer “was noted among patients with the longest exposure to pioglitazone, and in those exposed to the highest cumulative dose of pioglitazone.”
Compared with people who never used pioglitazone, those who were treated with the drug for more than 2 years had a hazard ratio for bladder cancer of 1.4 (95% CI, 1.03-2.0). The FDA calculated that among patients who used pioglitazone for more than 12 months, there would be 27.5 excess cases of bladder cancer per 100,000 person-years of follow-up (compared with patients who never used the drug).
The FDA also said it was “aware” of the French epidemiological study that sparked the European suspensions. The French study documented a significantly greater overall risk for bladder cancer among people who took pioglitazone than among those who took other diabetes drugs (HR, 1.22; 95% CI, 1.03-1.43), as well as a significantly elevated risk among people who used the drug for longer than 1 year (HR 1.34; 95% CI, 1.02-1.75).