A Better Beta Blocker for Heart Failure

July 3, 2003 -- Coreg improves survival in heart failure patients better than another widely used drug. The first study comparing the two beta-blocking drugs assessed future outcome in heart-failure patients.

The Carvedilol or Metroprolol European Trial (COMET) involved more than 3,000 patients in 15 countries, with varying degrees of chronic heart failure -- making it the largest study ever done on either drug. Carvedilol is known as Coreg; metroprolol as Lopressor.

Half of the patients were given Coreg and the other half received Lopressor. They were followed for nearly five years, and didn't know which medication they got.

Considerably Longer Life

By study's end, 34% of Coreg patients had died, compared with 40% of those taking Lopressor -- that's a 17% lower death rate in patients on Coreg. Researchers estimate the average survival was 1.4 years longer in the Coreg group.

The improvement in life expectancy is considerable because this condition has a high death rate despite treatment, writes Henry J. Dargie, in an editorial that accompanies the study in this week's The Lancet.

"It's a fairly clear and definitive result: Carvedilol, in this trial, has been shown to be very much better than metroprolol," lead researcher Philip Poole-Wilson, MD, FRCP, tells WebMD.

Beta-blocker drugs are often used to treat heart failure -- which affects nearly 5 million Americans -- because they slow heart rate, reduce blood pressure, and ease the flow of blood from the heart to the rest of the body. These drugs also are used for high blood pressure, angina, and other cardiovascular problems. They work by blocking "beta" receptors that send chemical messengers to increase heart rate.

Old Still Better Than New?

The COMET findings were presented last week in France at the Heart Failure 2003 meeting of the European Society of Cardiology. There, some questioned why a newer long-acting version of Lopressor, Toprol XL, wasn't used in the study. COMET was sponsored by F. Hoffmann-La Roche and GlaxoSmithKline, which market Coreg in the U.S. and as Dilatrend elsewhere. (GlaxoSmithKline is a sponsor of WebMD.)

Poole-Wilson, professor of cardiology at Imperial College in London, tells WebMD what he told them: The slow-release Lopressor formula -- the more widely used version in the U.S. -- was the only one available when the study began. But two experts not connected with the study say the long-action formula wouldn't likely affect study results.

"The Lopressor formula, taken twice daily was done in COMET, delivers the same dosage of beta-blocking properties as the newer Toprol XL tablet taken once daily," says Howard Eisen, MD, director of the Advanced Heart Failure and Transplant Center at Temple University School of Medicine.

'This Is Really Remarkable'

"This is a significant finding because it shows that one effective drug is better than another effective drug."