FDA restricts use of Sanofi-Aventis' Ketek; orders strict new labeling with a 'boxed warning'.

After months of analysis and public discussion, the US Food and Drug Administration (FDA) announced in mid-February that it was restricting the use of Sanofi-Aventis SA's controversial antibiotic Ketek. The drug's package will also carry a strict new warning on its risks and how to use safely. Ketek has been linked to rare reports of acute liver failure that have resulted in several deaths and several patients needing a liver transplant. (Transplant News, January 2007)

The FDA said the changes include the removal of two of the three previously approved indications - acute bacterial sinusitis and acute bacterial exacerbations of chronic bronchitis - from the drug's label. "The agency has determined that the balance of benefits and risks no longer support the approval of the drug for these indications. Ketek will remain on the market for treatment of community acquired pneumonia of mild to moderate severity (acquired outside of hospitals or long-term care facilities)," the agency said in a press release.

In addition, FDA worked with Sanofi-Aventis to update the product labeling with a "boxed warning," the agency's strongest form of warning. The warning states that Ketek is contraindicated in patients with myasthenia gravis. The company will also develop a Patient Medication Guide that informs patients about the risk of the drug and how to use it safely.

The changes followed the recommendations of an FDA advisory committee in December 2006, calling for the label to be modified to limit the drug's use.

The House Energy and Commerce Committee held an open hearing on how the FDA handles drug-safety issues the day after the FDA ruling. A former employee of the Sanofi-Aventis contractor that oversaw the clinical trial of the antibiotic testified the drug maker knew there was evidence of a problem with the study before FDA regulators discovered the problem, according to the Wall Street Journal.