Actos and bladder cancer

Several studies show a link between Actos and bladder cancer. In 2005, a group of researchers working to determine the cardiovascular risks of the drug noted a statistically significant increase in the number of cases of bladder cancer associated with prolonged use of Actos, as compared the the rest of the population.
In 2010, the FDA issued a Safety Announcement to declare that they were looking into the findings of this study and others, and in 2011, the organization issued a follow-up warning, noting that prolonged use of Actos may be associated with an increased risk in bladder cancer. Subsequent studies have shown that this increase in risk may be as high as 40% for patients taking the drug for 12 months or more.