Multaq Liver Problems Are Being Monitored in Canada

Canadian health officials are joining the growing number of countries that are monitoring the potential side effects of Multaq, a relatively new heart drug, for links to liver failure and other liver problems. 

Health Canada began a review of Multaq after the FDA announced earlier this month that it is requiring the drug to carry new warnings about the possibility of severe liver problems with Multaq.

Although there have been at least two reported cases of liver failure requiring a transplant among users of Multaq and several other reports of liver injury in the United States, there have been no adverse reaction reports in Canada involving Multaq liver problems.

The European Union is also reviewing Multaq for liver damage links, and last week Sanofi-Aventis sent letters to healthcare providers in Europe detailing the two cases of acute liver failure which played a crucial role in the FDA’s decision to add new label warnings to the drug.

Multaq (dronedarone) was approved in July 2009 for the treatment of patients who have had abnormal heart rhythms in the last six months. In less than two years since its approval, there have been at least 492,000 Multaq prescriptions in the United States filled by about 147,000 patients at outpatient pharmacies across the country. In addition, the drug can be given to patients being treated in hospitals.

The two cases of acute Multaq liver failure and transplantation that preceded these warnings in the United States and Europe both occurred in women about 70 years of age. One suffered liver failure after six months on Multaq and another after only four and a half months. Both had atrial fibrillation problems. In both cases, doctors found signs of extensive cellular death in the liver, and in both cases they ruled out other possible causes of liver failure.

Canadian health officials reported they have only received about 40 adverse event reports concerning Multaq between its launch and October 31, 2010. None of those cases involve liver damage from Multaq.