Xifaxan drug receives FDA approval

The U.S. Food and Drug Administration today approved the use of Xifaxan for reduction in the risk of the recurrence of overt hepatic encephalopathy (HE) in patients with advanced liver disease. This is a new use for Xifaxan (rifaximin), a drug that has been approved for the treatment of traveler's diarrhea.

Hepatic encephalopathy is a worsening of brain function that can occur in patients whose liver can no longer remove toxins from the blood. Increased levels of ammonia in the blood are thought to play a role in the development of HE, and Xifaxan works by reducing these levels.  

"The approval of Xifaxan for this new indication provides an additional treatment option for patients with liver disease," said Joyce Korvick, M.D., deputy director for safety of FDA's Division of Gastroenterology Products. "Hepatic encephalopathy occurs commonly in patients with liver disease, and there are few effective treatments for this serious condition."

The efficacy of Xifaxan was established in a randomized placebo-controlled clinical trial of adult patients from the United States, Canada, and Russia. Patients with liver disease who entered the trial had no or mild symptoms of HE. Patients treated with Xifaxan were less likely to develop HE during the trial, compared to placebo-treated patients.

Xifaxan was not studied in patients with the most severe forms of liver disease. Since most patients were also taking lactulose (a synthetic sugar which helps prevent absorption of ammonia from the intestine) during the trial, the efficacy of Xifaxan as a stand-alone treatment for HE could not be assessed.

The most common adverse reactions reported with the use of Xifaxan in patients with liver disease include swelling of the arms and legs (peripheral edema), nausea, gas, and headache.  

Xifaxan received a priority review under FDA's new drug application process and was granted orphan designation status. Xifaxan is manufactured by Salix Pharmaceuticals Inc. of Morrisville, N.C.