Though a 10-year epidemiologic study did not find an increased risk of bladder cancer with pioglitazone use, the Food and Drug Administration has chosen to affirm the warning on the label of the type 2 diabetes drug following an updated review of several studies.
The FDA issued a warning about the possible risk of bladder cancer based on interim results from the 10-year epidemiologic study in 2010, and it changed the labels of pioglitazone-containing medicines in 2011 to include warnings about this risk.
In the 10-year prospective cohort study of 158,918 patients who never took pioglitazone and 34,181 patients who had taken pioglitazone at some point, use of pioglitazone, compared with never use of pioglitazone, was not associated with an increased risk for bladder cancer (hazard ratio, 1.06; 95% confidence interval, 0.89-1.26).
There was a modest trend toward higher risk with increasing duration of use, but the trend was not statistically significant. Compared with the interim 5-year results, these final 10-year results found weaker associations that were not statistically significant.
The directions of the associations, however, remained unchanged. Based on these findings and other reviewed studies with conflicting results, the FDA has concluded that use of pioglitazone may be linked to an increased risk of bladder cancer.
The labels of pioglitazone-containing medicines already contain warnings about this risk, but the FDA has now approved label updates to describe the additional studies reviewed.
Read the FDA update and data summary here.
lnikolaides@frontlinemedcom.com
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