Controversial Heart-Surgery Drug Aprotinin Is Under Fire. Bayer’s controversial heart-surgery drug aprotinin, marketed as Trasylol, is under fire yet again thanks to a new study that found that the drug carries with it an increased risk of long-term mortality. Trasylol is a widely used drug intended to reduce bleeding during open-heart surgery. The study appears in the February 7 issue of the Journal of the American Medical Association.
Researchers, led by Dr. Dennis T. Mangano of the Ischemia Research and Education Foundation (IREF), concluded that “in addition to the previously reported acute renal and vascular safety concerns, aprotinin use is associated with an increased risk of long-term mortality following CABG [coronary artery bypass graft] surgery. Use of aprotinin among patients undergoing CABG surgery does not appear prudent because safer and less expensive alternatives (ie, aminocaproic acid and tranexamic acid) are available.”
The new observational study of 3876 patients from 62 medical centers was conducted between November 11, 1996, and December 7, 2006. Survival rates were assessed at 6 weeks, 6 months, and annually for 5 years after CABG surgery. The results were rather alarming: During the five-year examination period, 223 deaths occurred among 1072 aprotinin-treated patients, equal to 20.8 percent of the group. That death rate was nearly two-thirds greater than that of control patients (12.7 percent). After controlling for various patient factors, the results showed that Trasylol patients faced a 48 percent greater risk of death within a five-year period than those not using any medication.
Patients treated with aminocaproic acid had a death rate of 15.8 percent and those treated with tranexamic acid patients had a death rate of 14.7 percent, meaning either of these two alternative therapies carries with it a significantly lower mortality risk than aprotinin. Significantly, the authors noted that “serious safety concerns extend beyond the perioperative period” and that “their consequences likely continue over months to years following administration of aprotinin.”
Findings May Have Serious Clinical Implications
The findings of this study may have serious clinical implications. As the researchers wrote, “We estimate that over the past year, aprotinin was prescribed worldwide to at least 200,000 cardiac surgery patients having a profile similar to patients in our study. For such patients, our study found a 5 percent absolute increase in 5-year mortality (1 percent per year for 5 years) associated with aprotinin use, compared with either aminocaproic or tranexamic acid use. Thus, in 2006 alone, had aprotinin been replaced with either of these generic agents, we estimate that approximately 2,000 deaths per year for the next 5 years (or 10,000 total deaths) might have been avoided.”
In an editorial accompanying the report, Dr. T. Bruce Ferguson Jr. wrote, “This past year has been a complicated one for aprotinin, an antifibrinolytic serine protease inhibitor used to lessen bleeding in patients undergoing cardiac surgery with cardiopulmonary bypass. Thirteen years after the initial approval of aprotinin by the U.S. Food and Drug Administration, the report by Mangano and colleagues … will intensify the debate about the benefits and risks associated with use of this drug. Perhaps more important, this aprotinin story illuminates the larger issue of postmarket safety evaluation surrounding drugs and devices in the current medical environment.”
Bayer has suffered a number of setbacks related to Trasylol in recent months. An IREF study published early last year reported an increase in the possibility of kidney failure, heart attack, and stroke in Trasylol patients compared to those treated with other drugs. A second study also noted an increased risk of kidney damage.
In addition, on September 27, 2006, a week after the FDA held a public meeting of the Cardiovascular and Renal Drugs Advisory Committee to discuss the safety and risk-benefit profile for Trasylol, Bayer admitted to having conducted an additional internal study, which found that, in addition to severe kidney damage, Trasylol may increase the chance for death, congestive heart failure, and strokes. A few weeks ago, the company decided to halt three clinical trials that were intended to expand the approved usage of the drug, which currently is only approved for use in the course of coronary artery bypass graft surgery.
Bayer said the findings of this most recent study were “not reliable,” citing “major differences in clinical practice among the contributing countries” and questioning the authors’ “methodological and analytical approaches.”