Aventis reports liver problems with Arava

Aventis Pharma is issuing a letter to health care professionalsfollowing reports that some patients taking Arava (leflunomide) to treat active rheumatoid arthritis develop liver injury due to an increase in some liver enzymes which can lead to conditions such as hepatitis and liver failure. The company says, however, that it is difficult to identify definitively a specific cause for liver injury as RA patients often have other serious medical conditions and take several drugs in their treatment regimen which could be toxic to the liver.