The U.S. Food and Drug Administration has announced that it is reviewing safety data on the diabetes drug Actos (pioglitazone).
The agency recently received preliminary results from a long-term study suggesting an increase in the risk of bladder cancer among patients taking Actos for the longest time with the largest cumulative doses.
A signal for bladder cancer with the drug was seen in preclinical studies in rats and in two controlled clinical trials. The 10-year observational study of nearly 200,000 patients with diabetes in the Kaiser Permanente Northern California health plan, is being conducted by the manufacturer, Takeda Pharmaceuticals North America Inc., specifically to examine this association. The results submitted to the FDA were from a planned 5-year interim analysis. They showed no overall increase in the risk of bladder cancer among patients taking Actos; however, once patients had been taking the drug for 2 years, the risk increased significantly, in a dose-dependent manner, according to the FDA.
Although it has begun a safety review, the FDA has not concluded that Actos increases bladder cancer risk, and the agency has advised patients to continue taking the drug unless instructed otherwise by their health care providers. Results of the review are expected to be announced in several months, the agency wrote.