Metformin Fails To Reduce Bladder Cancer Risk, Safer Than Actos: Study

Researchers were disappointed to find that the drug metformin did not reduce the risk of bladder cancer among individuals with type 2 diabetes, but they did find that it does not increase the bladder cancer risk, like several studies have suggested side effects of Actos does.  

In a study published this month in the medical journal Diabetes Care, researchers from the University of Pennsylvania’s Abramson Cancer Center found that patients taking metformin or drugs from a class known as sulfonylureas, like Dymelor and Orinase, did not see a reduction in the rate of bladder cancer.

Bladder cancer is a potential risk that may be associated with diabetes, and researchers hoped that the diabetes drug metformin may have a prophylactic effect. However, after looking at data involving 87,000 patients with diabetes in The Health Improvement Network, researchers indicate that they found no statistical difference in the bladder cancer rates among those who took the drugs and those who did not.

Researchers did recommend scientists take a look at metformin in comparison to other cancer rates as well, as bladder cancer is only one type of cancer some believed metformin may help prevent.

“Use of metformin is not associated with a decreased incidence of bladder cancer,” the researchers concluded. “Similar methods should be used to study other cancers that have previously been identified as potentially preventable with metformin.”

Actos Bladder Cancer Risks

The study comes amid continuing concerns about the link between bladder cancer and Actos, a competing diabetes drug.

While all diabetes patients may face a slight increase in the risk of bladder cancer, several studies have suggested that long-term Actus users face a substantially increased risk.

Concerns surfaced in September 2010, after interim data from an on-going 10 year study found that users of Actos may face an increased risk the longer the medication is used. Several European countries instituted an Actos recall after a review of insurance data also found the same increased rates of bladder cancer, and increased warnings were required in the United States.

In December 2013, researchers from the U.K. called for limits on Actos use due to the bladder cancer risk. Researchers indicated that doctors should limit Actos prescriptions to short durations to decrease the risk of users developing bladder cancer.

Takeda Pharmaceuticals currently faces about 3,000 Actos bladder cancer lawsuits filed on behalf of former users who allege that the drug maker withheld information and warnings about the potential risks.

In the federal court system, the Actos litigation has been centralized before one judge for coordinated handling, and the first trial is currently underway to help the parties gauge how juries are likely to respond to certain evidence and testimony that may be repeated throughout other cases. The outcome of this case is being closely watched by lawyers involved in the lawsuits, as it may facilitate further negotiations to reach Actos settlements for users diagnosed with bladder cancer.