Bayer’s Trasylol: What Really Happened?

Trasylol, the drug used in heart surgery to limit bleeding, has been controversial from its inception. Several studies have been conducted showing the drugs correlation to kidney failure, increased risk of heart attacks and strokes and claims have been made that over 20,000 patients may have died while Bayer Pharmaceuticals reaped the profits. So, what really happened?

The following timeline shows the drug’s history, the alleged cover-ups and the devastating results:


According to a recent 60 Minutes interview, Dr. Juergen Fischer, the Director of the Institute of Experimental Medicine at Germany’s University of Cologne, had studied the effects of Trasylol on animals in the 1980’s. He found a direct link between the drug and renal (kidney) failure. Concerned, he reported his findings to Bayer. However, he told 60 Minutes correspondent Scott Pelley that he “felt that Bayer wasn’t interested to examine these side effects.”


Dr. Nicholas Kouchoukos, a heart surgeon at the Missouri Baptist Medical Center, also studied the effects of Trasylol – but on humans. Although his study only included 20 patients, he told Pelley that 13 out of the 20 patients had problems with kidney functions after being exposed to the drug.


Although the above studies revealed a correlation between Trasylol and kidney failure, they were small in nature and the Food and Drug Administration (FDA) approved the drug in 1993.

1993 – 2006

It’s been reported that well over 4 billion patients were given Trasylol during this time. Bayer aggressively marketed the product and priced it much higher than similar drugs that doctors say provide the same results – but at a cost far less expensive than Bayer’s price of $1,000. It has been reported that similar drugs only cost around $50. During these years, Bayer’s sales of the product grew to an estimated $750 million to $1 billion per year.


Dr. Dennis Mangano conducted another study on the effects of Trasylol use, but this time, the study was much larger – and therefore, more credible. Published in the New England Journal of Medicine in January 2006, Mangano studied approximately 5,000 Trasylol patients in 17 countries and found that patients on the drug doubled their risk of kidney and heart failure and had a 181 percent increase in the risk of stroke. In a February 2008 interview with Pelley, Mangano suggested that 22,000 patients may have died unnecessarily due to the drug’s usage.

In response to Mangano’s study, Bayer did a study of its own. It hired Dr. Alexander Walker to review over 70,000 patient records to prove Mangano wrong. However, Walker’s results didn’t prove Mangano wrong at wrong at all. Although Walker allegedly submitted his findings to Bayer, the company never released them to anyone – including the FDA.


A Canadian biological activity reaction test (BART) was conducted on Trasylol and two similar aprotonin drugs in 2007. The independent, randomized and controlled trial was being conducted on 3,000 high-risk cardiac surgery patients; however, the trial was never completed because patients taking Trasylol were dying.

November 2007

After the Canadian trial’s ‘results’ were made public, Germany and Canada suspended Trasylol marketing and the FDA followed suit soon afterwards.

According to news reports, Bayer’s Trasylol was given to an estimated one third of all heart bypass patients in the United States over the 14 years it was on the market from 1993 to 2007. It seems clear that Bayer knew about the harmful, and perhaps deadly, effects associated with the drug – but did nothing. Bayer Pharmaceuticals 2007 income will likely report record profits for 2007 – a large part of it due to the sale of Trasylol.

If you or a loved one may have been injured or died due to the use of Trasylol, contact an attorney whose practice focuses in this area of law to discuss your situation. The consultation is free and without obligation. To contact a qualified attorney, please click here.

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