The US Food and Drug Administration said it will re-evaluate Bayer AG's Trasylol blood-clotting injection after an independent panel on drug safety warned it of an increased risk of death from the drug.

The Data Safety Monitoring Board (DSMB) recommendation to stop patient enrollment in a study to compare Trasylol with other antifibrinolytic drugs, the FDA said on its web site.

Trasylol, which is given before coronary bypass surgery to prevent excessive blood loss, was associated in the study with 'more deaths due to haemorrhage' compared with other blood-clotting drugs, the FDA added.

The drug, approved in 1993 and known generically as aprotinin, has been under a cloud for more than a year amid data suggesting it may boost the risk of death, serious kidney damage and stroke.

The U.S. Food and Drug Administration advised doctors in a notice posted on its Web site on Thursday to be aware of the increased risk of death.

The FDA said it will revisit Trasylol's safety, which may include label changes or other regulatory actions.

Trasylol is aimed at preventing blood loss in patients with an increased risk for blood loss during heart bypass surgery.

Bayer said it still backs the safety of Trasylol, and that it is cooperating with the FDA and other health regulators to "reevaluate" Trasylol's risks and benefits.

The FDA said in its notice to doctors that the 30-day mortality risk in the Trasylol group in the trial was nearing statistical significance, compared with other treatments it was tested against. Trasylol was linked to less serious bleeding but more deaths due to hemorrhage in an initial analysis.

In September 2007, n FDA advisory panel recommended Trasylol stay on the market despite its risks but urged the company to conduct a randomly-controlled clinical trial, a rigorous study that is considered the gold standard for evaluating a drug.