FRANKFURT, Germany - Pharmaceutical company Bayer AG suspended global marketing of its anti-bleeding drug Trasylol on Monday after a Canadian clinical trial found that it could be linked to a higher risk of death than other such drugs.
Leverkusen, Germany,-based Bayer said it made the decision after talks with the U.S. Food and Drug Administration, Health Canada and the German Federal Institute for Drugs and Medicine Products.
Trasylol is designed to stem blood loss and enable patients receiving heart bypass surgery to avoid transfusions.
Monday's announcement came in the wake of a Canadian study, known as the BART trial, that compared the safety and efficacy of Trasylol with two others.
That trial was halted after preliminary results suggested Trasylol increased the risk of death when compared with the other drugs.
Trasylol, also known as aprotinin, works by blocking enzymes that dissolve blood clots.
The FDA approved it in 1993. It began re-evaluating the drug's safety after the January 2006 publication of two studies that linked the drug's use to serious side-effects, including kidney problems, heart attacks and strokes.
More recent studies have suggested the drug also raised the risk of death. One of those studies had been withheld by Bayer from the FDA due to what a company investigation later characterized as a "regrettable human error."
Bayer said Monday it wanted to review the results from the Canadian trials before moving forward.
"Once the complete ... dataset is available, Bayer will work with health authorities to evaluate whether these data have any impact on the positive benefit-risk assessment for Trasylol," the company said.
"At that time, the temporary marketing suspension will be re-evaluated."
In late October, the FDA said that "in light of the preliminary BART study findings, (the) FDA anticipates re-evaluation of the overall risks and benefits of Trasylol."
Bayer also issued new guidance to doctors at that time, telling them they should only use Trasylol as directed on the drug's label while records of the multi-centre, multi-year trial were reviewed.
The BART trial was testing the drug against two other medications in the same class.
The principal investigator of the trial was Dr. Paul Hebert, a researcher at the Ottawa Health Research Institute. Hebert is also editor of the Canadian Medical Association Journal.
The study's full name is "Blood Conservation using Antifibrinolytics: A Randomized Trial in High-Risk Cardiac Surgery Patients," but it goes by the acronym BART.
It is a multi-centre randomized controlled trial to compare the efficacy and safety of aprotinin, aminocaproic acid and tranexamic acid.
Approximately 3,000 high-risk cardiac surgical patients undergoing either reoperation for coronary heart bypass graft or aortic valve replacement, or combined valves or valve-graft procedures were to be randomly assigned to one of the drugs.
When a periodic analysis of data from the trial showed increased deaths among the aprotinin group, the trial's executive board decided to cut off enrolment in the study and informed drug regulators and the company.