How Many of the People Who Took Actos Will Develop Bladder Cancer?

When the second FDA Actos bladder cancer warning was issued on June 15, 2011 talking about an increase in the risk of developing bladder cancer after taking the diabetes drug Actos, millions of Actos users were left wondering just how much of an increased risk the drug posed.   Statistically, bladder cancer is seen in 1 in 500 people.  Actos was approved by the FDA in 1999 and was the best-selling diabetes medication with peak sales around 2007, with nearly 2.5 million users in the US alone at that time.   So assuming that 5 million people will have used Actos by the end of the year, 12 years since it was on the market, 10,000 of those persons would be expected to develop bladder cancer.   While the exact cause of bladder cancer is not known, it is known that exposure to certain chemicals, toxins and drugs can dramatically increase the risk of developing bladder cancer.  At the present time it isn’t known how much taking Actos increases the risk of bladder cancer and if ongoing use makes the risk even greater or if a lifetime threshold amount alone increases the risk and further use does not proportionally increase either the risk of developing bladder cancer or the severity of the cancer if it does occur.   There is an Actos bladder cancer study being conducted by the manufacturer, but it won’t be completed for several more years; however, interim results were behind the FDA’s first safety notice regarding Actos and bladder cancer.  Meanwhile, Actos has been recalled in France and new prescriptions suspended in Germany.  As Actos prescriptions continue to be filled in the US, as well as new patients being placed on the drug, the number of Actos bladder cancer cases in the US will likely grow.