FDA drug safety officials say that an influx of numerous bleeding reports associated with Boehringer Ingelheim’s blood thinner Pradaxa (dabigatran) is a case of “stimulated reporting” caused by the drug’s novelty and related media coverage.

Writing in the New England Journal of Medicine, the officials said FDA confirmed through its Mini-Sentinel system that Pradaxa’s bleeding rates are not higher than those for warfarin, a finding consistent with the company’s RE-LY study that was used as a basis for approval.

“Because the RE-LY trial had clearly shown that bleeding was a serious side effect of dabigatran, it was expected that bleeding events would be reported… but the number of reports was sufficiently high to prompt the FDA to initiate a review,” the officials wrote. “The case review did not identify any unrecognized risk factors for bleeding, and there was generally no indication that dabigatran was not being used in accordance with its labeled directions.”

The FDA officials noted that there are limitations to the Mini-Sentinel analysis, “including lack of adjustment for confounding variables and lack of a detailed medical record review,” and said “we are now conducting two protocol-based assessments, using claims data from Mini-Sentinel and other claims databases, in which adjustments will be made for confounding factors.”