Following the findings of a clinical trial in Ottawa and being linked to a 50% greater risk of death than competing drugs, Trasylol, Bayer AG's anti-bleeding drug has been taken off the market for two months or more.
American (FDA) German (the German Federal Institute for Drugs and Medical Devices) and Canadian (Health Canada) regulators have advised Bayer to defer sales until the initial findings of the BART trial have been appraised.
Because it is concerned that supplies of alternative medicines may not be in sufficient supply, a phased withdrawal of the drug has been requested, however.
Health Canada spokesperson Jirina Vlk has stated that the institution will see to it with Bayer's cooperation that the drug is still accessible for certain surgeries.
"Bayer Inc. will work with Health Canada so that the drug can be made available to certain patients in cases where the doctor believes the substantial benefit clearly outweighs the risk," she said.
Some cardiac surgeons, such as Sunnybrook Health Sciences Centre's Dr. Gideon Cohen, though, are already resorting to alternative medications in light of the BART (Blood conservation using Antifibrinolytics in a Randomized Trial ) findings.
"…because the cases now for cardiac surgeons are becoming more and more complex and more and more high risk. Although bleeding is a major risk, I think that I'd have to really believe that aprotinin is better than the other agents and have conclusive evidence that it is before I would use it again," he said.
The BART trial which was the first to test aprotinin against other drugs tested it against tranexamic acid and aminocaproic acid, which are all used to stem the loss of blood at a bypass operation, thus reducing the necessity of blood transfusions.
At the BART trial conducted by doctors at Ottawa's Health Research Institute 2,973 heart surgery patients were randomly administered any one of the three drugs. Contrary to expectations, the tests revealed that 2,163 subjects were more prone to mortality after being given the far more expensive Trasylol. In real numbers this worked out to an additional 2deaths for each 100 of those receiving Trasylol in comparison to the others who received the alternate antifibrinolytics.
Following these findings the data safety monitoring board stopped the trials and announced that the drug would be re evaluated.
Bayer has said in a statement that it still believed Trasylol was beneficial when used as directed. The F.D.A. said it would try to accommodate doctors who still wanted to use the drug and permit Bayer to supply it as part of a study.
The drug has also been suspended in Australia. The product has not been recalled, but additional stocks will not be distributed until the end results of the Canadian trial are finalized.
