Diabetes drug manufactured by Takeda Pharmaceuticals is associated with increased risk of bladder cancer, a new study says.

According to research, taking pioglitazone daily for two years can double risk for bladder cancer. However, in absolute terms the risk is low, just a few hundred people out of a hundred thousand may have cancer.

The drug pioglitazone is known by its brand name Actos.

The drug, in the past, was associated with weight gain and risk of heart failure.

For the study, the research team analyzed medical records of some 115,727 patients who were diagnosed with diabetes between 1988 and 2009.

The team found 470 people were diagnosed with bladder cancer. The researchers say that people on pioglitazone were 83 percent more at risk of developing bladder cancer.

But, no such risk was reported in a similar drug rosiglitazone or Avandia.

"It can confidently be assumed that pioglitazone increases the risk of bladder cancer. It also seems that this association could have been predicted earlier," said Dominique Hillaire-Buys and Jean-Luc Faillie, Department of Medical Pharmacology and Toxicology in Montpellier, France in an editorial in BMJ.

"Prescribers who are ultimately responsible for therapeutic choices can legitimately question whether the benefit-risk ratio of pioglitazone is still acceptable for their patients with diabetes," they suggest.

"Takeda is confident in the therapeutic benefits of Actos and its importance as a treatment for type 2 diabetes. As a science and evidence-based company, Takeda firmly stands behind the substantial data available confirming the positive risk/benefit profile of Actos, which includes more than 12 years of clinical and patient experience with the product," Elissa J. Johnsen, a spokesperson for Takeda Pharmaceuticals told WebMD in a statement.

"As a company, Takeda is committed to ongoing clinical research to understand and investigate potential safety concerns, and is currently supporting several ongoing studies, including a 10-year epidemiological study, investigating the potential relationship between Actos and bladder cancer," Johnsen said, reports WebMD.  

The study is published in BMJ.