Bayer AG is removing remaining supplies of its heart-surgery drug Trasylol from the U.S. market after a long-awaited study found it raised the risk of death compared to two alternatives, U.S. regulators said on Wednesday. The announcement followed publication earlier on Wednesday of a Canadian study by the New England Journal of Medicine that showed patients given Trasylol had a more than 50 percent higher death rate than patients who got other, cheaper drugs.

"Thus, in all likelihood, this is the end of the aprotinin story," Dr. Wayne Ray and Dr. Michael Stein of Vanderbilt University in Tennessee wrote in a commentary on the study. The expensive drug, also known by its generic name aprotinin, has been widely used since the 1990s during heart bypass surgery to reduce bleeding. Bayer pulled the drug in November, saying it would reevaluate its options once details from the new study, known as BART, were released.

The Food and Drug Administration said on Wednesday Bayer had notified the agency that it would begin removing remaining Trasylol stock from the U.S. market. Access will be limited to investigational use for certain patients who have no acceptable alternatives, the FDA said. The FDA "supports Bayer's decision to completely remove Trasylol from regular use in the U.S. market," the agency said.