More Than 1,000 Reported Actos Bladder Cancer Diagnosis to FDA

According to a recent review of adverse event reports submitted to the FDA, the federal health regulators received more than 1,000 complaints over a 15-month period involving individuals diagnosed with bladder cancer on Actos, providing further evidence that the popular diabetes drug increases the risk of bladder cancer.

The Institute for Safe Medication Practices (ISMP) issued a quarterly drug report (PDF) early this month, which looked at complaints submitted during the first quarter of 2012 to the FDA’s MedWatch Adverse Event Reporting Program.

Since January 2011, more than 1,000 reports have now been filed on behalf of individuals who received a bladder cancer diagnosis after taking Takeda Pharmaceutical’s Actos, leading the group to conclude that there is little doubt that there is connection between Actos and bladder cancer, despite Takeda’s claims to the contrary.

“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,” the report states. “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 1,025 Actos bladder cancer reports the FDA has received since the beginning of 2011, 235 reports were filed in the first quarter of 2012 alone. About 71% were reported by consumers, and 29% by health care professionals.

The report notes that the first signs of bladder cancer linked to Actos was seen in rat and mice studies conducted back in 1999. FDA reviewers had reservations about the drug after the rates suffered multiple toxicities in vital organs. They were also concerned about the relatively low dose margin of safety. The rodents could only take the equivalent of seven times the human dose. One of the side effects suffered by the rats was increased incidences of bladder cancer.

Takeda Pharmaceuticals has maintained that the medical community should hold off on reaching any conclusions about the cancer risk with Actos until the conclusion of an on-going 10 year study, which was launched in 2003. However, interim data from the study at the five year mark suggested an increased incidence of bladder cancer among Actos users

The FDA launched a safety review of Actos in September 2010, after receiving the early data from this on-going study. The following summer, a study conducted by French insurers further increased concerns within the medical community about an increased risk of bladder cancer diagnosis following Actos use, leading to a decision to remove Actos from the market in France.

In the United States, the FDA added new warning language to the Actos warning label in August 2011, indicating that use of the drug for more than one year may increase the risk of bladder cancer.

Hundreds of individuals throughout the United States are now pursuing an Actos bladder cancer lawsuit against Takeda Pharmaceuticals, alleging that the drug maker failed to research the side effects of the drug or provide adequate warnings about the risks associated with long-term use.