Food for Thought: Boehringer Ingelheim Puts Pradaxa Cards on the Table

When German pharma company Boehringer Ingelheim on November 12 said that 260 cases of fatal bleeding have been linked to its new stroke prevention pill Pradaxa, the figures were taken up by many media as evidence that Pradaxa dabigatran, which was launched in Europe in September this year, was a dangerous drug.

In a courageous move, Boehringer Ingelheim yesterday released detailed data from the drug safety database, data that are usually submitted to regulatory agencies only.

Now that the figures are out, several media have taken up the issue again to put it into perspective. Hartmut Wewetzer in Der Tagesspiegel writes that every drug inhibiting blood coagulation poses the risk of bleeding. Wewetzer cites Christoph Bode, a heart specialist from University Clinic Freiburg, as saying that Pradaxa is lowering the risk of fatal bleeding in the brain to 25%, which is a superior value compared to vitamin K antagonists such as Marcumar and Warfarin, the therapeutic standard of previous decades.

Wewetzer also features Boehringer’s calculation that – based on current data – Pradaxa each year can prevent 3,490 of 4,500 stroke cases among 100,000 patients with atrial fibrillation, but may cause 230 cases of fatal bleeding. In comparison, Warfarin is causing 330 deaths. Based on the sum total treatment duration of Pradaxa, which amounts to 410,000 patient years since market authorization, Pradaxa is causing 63 fatal cases among 100,000 patients and year, much less than the figures to be expected from the clinical study data.

Martina Lenzen-Schulte in Frankfurter Allgemeine Zeitung (FAZ) states that the figures reported do not constitute a scandal: “For one, it is in the nature of things that application of blood thinners can cause severe and sometimes fatal bleedings. And the bigger the number of patients treated, the more such complications are to be seen. … Second, it has to be asked whether the incidence of fatal bleedings following dabigatran administration is within the expected limits and – more importantly – whether conventional anticoagulants would have performed better.”

In her article “Deadly Speculations” Lenzen-Schulte also makes clear that competitors are often keen to scandalize side effects of novel drugs and mentions Bayer’s cholesterol-lowering drug cerivastatin as an example. Cerivastatin was withdrawn from the market by Bayer in 2001 following reports of fatal rhabdomyolysis. These cases mostly were due to combination with fibrate drugs – despite warnings on the label.

“It amounts to incapacitation, if one believes that patients always have to be dictated what it best for them”, she writes. “It would be better to put one’s cards on the table and let the patient decide what he wants and what not.”

Boehringer Ingelheim certainly has been quick to do just this, so that patients now can make an informed decision.