The Food and Drug Administration said Monday that Bayer AG has agreed to stop selling the drug, Trasylol, pending detailed review of preliminary results from a Canadian study that suggested an increased risk of death. The study comparing the safety and efficacy of the drug, Trasylol, with two others was recently halted.

Trasylol, also known as aprotinin, works by blocking enzymes that dissolve blood clots.

There are not many treatment options for patients at risk for excessive bleeding during cardiac surgery, the FDA noted in its announcement. The agency said it was working with Bayer to phase Trasylol out of the marketplace in a way that does not cause shortages of other drugs used for this purpose.

Bayer has said it believes Trasylol remains a safe and effective treatment option, but that the company would work with the FDA and regulators in other countries to re-evaluate the drug's risks and benefits and determine where any label changes are needed.