According to a recent review of FDA adverse event reports, the FDA has received over 1000 reports from individuals reporting unexplained diagnoses of bladder cancer after Actos use. This comes after several prominent scientific reports linked Actos use to an increased likelihood of developing bladder cancer.
The institute for Safe Medication Practices (ISMP) recently analyzed Actos complaints reported in the first quarter of 2012. As of January 2011, there were already over 1000 reports filed by individuals who were diagnosed with bladder cancer after using Actos. The ISMP reports, "The cancer risks associated with prescription drugs rank among the most elusive of adverse effects to establish. The carcinogenic potential of scores of approved drugs was first demonstrated in pre-approval studies in rats and mice fed high doses for their two-year lifetimes. But seldom is human risk either confirmed or ruled out with clarity. The Type 2 diabetes drug pioglitazone (Actos) has proved to be the exception."Out of the 1000+ adverse event reports filed since 2011, about 70% were reported by consumers and 30% were reported by doctors and health care professionals.
The ISMP noted that the first indication that Actos increased the risk of bladder cancer was observed in rats in 1999. Initially, the FDA also had reservations about the fact that Actos was also linked to several toxicities in vital organs. In response to allegations, Takeda Pharmaceuticals remarked that it was waiting for the results from a 10-year study it has been conducting on Actos and its link to bladder cancer. The study began in 2003 and final results will be available in 2013. However, data up to this point indicates that there is an increased and easily observed link between Actos and bladder cancer.
In response to growing concerns, the FDA has introduced a black box warning on Actos in August 2011 regarding the Actos - bladder cancer link. France responded by conducting its own national study and eventually recalled Actos all together.
While research is pending about the nature of the scientific link between Actos and bladder cancer, lawsuits are also pending alleging that Actos manufacturer, Takeda Pharmaceuticals, failed to adequately warn patients about the adverse events linked to continued used of their products.