The U.S. Food and Drug Administration has approved Multaq tablets (dronedarone) to help maintain normal heart rhythms in patients with a history of atrial fibrillation or atrial flutter (heart rhythm disorders). The drug is approved to be used in patients whose hearts have returned to normal rhythm or who will undergo drug or electric-shock treatment to restore a normal heart beat.

Multaq may cause critical adverse reactions, including death, in patients with recent severe heart failure. The drug’s label will contain a boxed warning, the FDA’s strongest warning, cautioning that the drug should not be used in severe heart failure patients.

“Multaq represents a therapeutic innovation for treatment of the heart rhythm disorder of atrial fibrillation,” said Norman Stockbridge, M.D., Ph.D., director of the Division of Cardiovascular and Renal Products in the FDA’s Center for Drug Evaluation and Research.

In a multinational clinical trial with more than 4,600 patients, Multaq reduced cardiovascular hospitalization or death from any cause by 24 percent, when compared with an inactive pill (placebo). Most of that effect represents reduced hospitalizations, especially hospitalizations related to atrial fibrillation. Atrial fibrillation and atrial flutter cause the heart to beat abnormally fast and sometimes prevent blood from being properly pumped out of the heart.

The most common adverse reactions reported by patients in clinical trials were diarrhea, nausea, vomiting, fatigue and loss of strength.

Multaq is manufactured by Paris-based sanofi-aventis.