An ongoing FDA epidemiological study supported the connection between the diabetes drug Actos (used to treat Type II diabetes) and the development of bladder cancer, particularly for patients taking Actos for a year or longer. The FDA warning against Actos came after two European countries banned the drug due to its possible risks.

Although 5-year data has shown no conclusive evidence linking Actos to bladder cancer, MedPage Today reported a 40% increased risk of bladder cancer in patients taking Actos, compared to patients who have never taken the diabetes medication.

MedPage also reported that Actos (Pioglitazone) "is now the second medication in the thiazolidinedione (TZD) class to be associated with serious side effects within the past year. Last fall, the use of rosiglitazone (Avandia) was severely restricted in the U.S. because of concerns about an increased risk of heart attack."