Blood thinner less risky for heart patients

LOS ANGELES (Reuters) - The blood-thinning drug Angiomax works as well as rival drugs, but with 47 percent less risk of major bleeding, to maintain blood flow in patients who have had a heart attack or severe chest pain, according to study results published on Wednesday.

A nearly 14,000-patient trial compared Angiomax, which is sold by the Medicines Co., to a combination of the blood thinner heparin plus a class of drugs called glycoprotein IIa/IIIb inhibitors. The inhibitors include ReoPro, made by Johnson & Johnson and sold by Eli Lilly & Co., MGI Pharma Inc.'s Aggrastat and Millennium Pharmaceuticals Inc.'s Integrilin, which is marketed by Schering-Plough Corp.

The study of patients with acute coronary syndromes assigned them to one of three treatment regimens in the emergency room -- heparin plus a glycoprotein IIb/IIIa inhibitor (GPI), Angiomax plus a GPI, or Angiomax alone.

Patients treated with Angiomax, also known as bivalirudin, had similar rates of serious complications, such as death, heart attack and repeat artery clearing procedures as the other groups, but had significantly lower rates of serious bleeding.

"Use of bivalirudin alone ... could prevent a significant number of major bleeding episodes and blood transfusions every year in the United States and elsewhere," said Dr. Gregg Stone, of the Columbia University Medical Center and the trial's lead investigator.

The Medicines Co. had reported preliminary results of the study in March. The full study was published on Wednesday in the New England Journal of Medicine.

Some cardiologists, however, have questioned the validity of the results, since the study included a 25-percent margin for claiming "noninferiority" for Angiomax.

"A 25-percent boundary is pretty wide," said Dr. Marc Cohen, director of cardiology at Newark Beth Israel Medical Center.

He also noted that 65 percent of patients treated with Angiomax in the study were first treated with heparin in the emergency room.

Stone said Angiomax was "clearly was noninferior," adding that high pretreatment levels are common in studies of patients with acute coronary syndromes who, after all, are being treated by emergency room personnel.

"Switching was a good thing in this trial," he said.

Stone added that Angiomax "is simpler to use and costs less," than the combination regimen.

The drug is currently approved as a replacement for heparin in nonemergency angioplasty procedures.