From the
Los Angeles Times:
Dronedarone, a highly touted drug targeted at atrial fibrillation and sold under the brand name Multaq, is only half as effective as the generic drug
amiodarone and does not appear to have fewer side effects, researchers from the Cedars-Sinai Medical Center reported Monday. It should be used only as a second- or third-line drug if all others fail, the team reported. The report, which is based on an examination of existing clinical trials rather than new research, represents further bad news for what was once thought to be a potential blockbuster drug with billions of dollars of annual sales.
Amiodarone, which is sold generically and under the brand name Cordarone, is an effective medication for controlling fibrillation. But it has severe potential side effects, including damage to the thyroid and lungs. Dronedarone was developed by Sanofi-Aventis as an alternative to amiodarone. It has a similar structure, but animal tests suggested it had fewer complications. The first clinical trial of the drug, in patients at moderate- to high-risk for hospitalizations and death from atrial fibrillation, showed that it doubled the rate of death, and the study was terminated prematurely. The FDA rejected the marketing application and suggested the company find applications where the benefit would exceed the risk.
A second major trial in patients with low to moderate risk found that the drug reduced hospitalizations resulting from atrial fibrillation, but not deaths. The FDA approved the drug, but allowed it to be marketed only for reducing hospitalizations.
European regulatory authorities demanded a head-to-head study of amiodarone and dronedarone. That study, which has yet to be published, found that dronedarone was only half as effective as amiodarone in preventing hospitalizations and deaths, but that it was slightly better tolerated -- although the difference was not statistically significant.
"The overall assessment is that dronedarone has only modest efficacy and no clear-cut safety advantage," Kaul said in an interview. Amiodarone, in contrast, has "a huge cost advantage." Multaq costs about $9 per day, and generic amiodarone costs pennies. "It's cheap, so why would you want to use an expensive, ineffective alternative?"
Kaul also thinks the side effects of amiodarone are a red herring. They appeared when a 400-milligram dose of the drug was routinely used, "but over the last 10 years, we have been using a 200-milligram dose and don't see the problems. I personally haven't seen any example of lung toxicity in the last 10 years.