Yet another study has confirmed the link between Actos and bladder cancer, finding that users face an increasing risk of developing the cancer the longer the diabetes drug is used.
In a study published this week in the Journal of the National Cancer Institute, researchers from the University of Pennsylvania found that Actos use was associated with a risk of bladder cancer that was two or three times higher than normal.
Researchers looked at data on about 60,000 patients in the United Kingdom from July 1, 2000 through August 31, 2010, finding that those who took Actos for less than five years had double the risk of a bladder cancer diagnosis, while those who used Actos for longer than five years had more than triple the risk.
Actos Cancer Concerns Have Grown Since 2010
Actos (pioglitazone) was developed by Takeda Pharmaceuticals and approved in the United States for treatment of type 2 diabetes in July 1999. It is a once-daily pill that increases the body’s sensitivity to insulin. Related medications that also contain the same active pharmaceutical ingredient include ActoPlus Met and Duetact.
Concerns about the potential link between bladder cancer and Actos surfaced in September 2010, after the FDA reported that they were investigating the potential risk based on interim data from an on-going study, which found an increased incidence of bladder tumors among users of Actos.
In June 2011, a study conducted by French insurers further confirmed that a higher-than-expected number of individuals were diagnosed with bladder cancer after using the medication, leading to an Actos recall in France and Germany due to the potential increased risk.
The medication has remained on the market in the United States, but the FDA updated Actos cancer warnings in August 2011, indicating that patients who use the diabetes drug for mor than a year may face an increased risk of bladder cancer.
So far this year, a number of studies have confirmed the risk of bladder cancer associated with long-term Actos use. A June 2012 study published in the British Medical Journal found that Actos may double the risk of bladder cancer after two years, and another study presented at the American Society of Clinical Oncology’s annual meeting in May suggested that the risk may apply to all drugs belonging to the same class of medications, known as thiazolidinediones, which also includes Avandia and Rezulin.
In this latest study, researchers also concluded that the risk of bladder cancer was seen with other medications in the same class. However, Actos is the only thiazolidinedione medication that remains widely available in the United States, as Rezulin was recalled in 2000 due to a risk of liver damage and severe restrictions were placed on the availability of Avandia last year due to an increased risk of heart attacks.
Lawsuits Over Actos and Bladder Cancer
A number of former users of the medication are now pursuing an Actos lawsuit against Takeda after developing bladder cancer, alleging that the drug maker failed to adequately research the medications or warn about the potential risks associated with using the drug for long periods of time.
In December 2011, the U.S. Judicial Panel on Multidistrict Litigation consolidated all cases pending in the federal court system as part of an Actos MDL, or multidistrict litigation, centralizing the cases before U.S. District Judge Rebecca Doherty in the Western District of Louisiana for pretrial proceedings.
The first Actos trial dates in the MDL have been scheduled for November 2014 and January 2015.