Treatment with the diabetes drug pioglitazone for more than 1 year may increase the risk of bladder cancer, the Food and Drug Administration announced in a safety communication issued on June 15.
A review of the 5-year data from an ongoing 10-year epidemiologic study of almost 200,000 patients with type 2 diabetes in the Kaiser Permanente Northern California health plan found that overall, there was no increased risk of bladder cancer among the patients who were treated with pioglitazone, compared with those who had never been treated with the drug, after adjusting for age, sex, use of tobacco products, use of other types of diabetes medications, and other risk factors. However, the risk did increase with higher doses and increasing duration of treatment: Treatment with pioglitazone for more than 12 months was associated with a 40% increase in the risk of bladder cancer, according to the FDA.
Pioglitazone, marketed as Actos, is approved for treating type 2 diabetes, and is also available in combination with metformin (Actoplus Met, Actoplus Met XR) and with glimepiride (Duetact).
The FDA is recommending that pioglitazone not be used in patients with active bladder cancer, and that it be used cautiously in patients with a history of bladder cancer.
The FDA is continuing to review the data from the 10-year study being conducted by the manufacturer, Takeda Pharmaceuticals North America, specifically to examine this association, and also plans to review the results of a French study that also found a significantly increased risk of bladder cancer associated with pioglitazone treatment, seen in men only. That study prompted French authorities to suspend the use of the drug in France and German authorities to recommend against starting pioglitazone treatment in new patients, earlier this month.
The statement is available at http://www.fda.gov/Drugs/DrugSafety/ucm259150.htm. Serious adverse events associated with pioglitazone should be reported to FDA’s MedWatch adverse event reporting program at 800-332-1088 or http://www.fda.gov/medwatch/.