Provided by Clinical Advisor
March 25, 2014
Patients assigned rifaximin experienced significantly fewer hepatic encephalopathy events compared with patients assigned placebo.
Rifaximin decreased hepatic encephalopathy episodes in patients with cirrhosis, new study findings show.
“[Rifaximin] is approved to treat urea cycle defects that prevent the removal of ammonia from the body,” Bruce F. Scharschmidt, MD, of Hyperion Therapeutics in San Francisco, said in a press release. “Our trial was the first to investigate the efficacy of a direct ammonia lowering agent in patients with cirrhosis and hepatic encephalopathy.”
The phase 2 study included 178 patients with cirrhosis, of which 59 were previously assigned rifaximin (XIFAXAN, Salix Pharmaceuticals). Researchers aimed to determine the proportion of patients with hepatic encephalopathy assigned twice-daily 6mL rifaximin vs. placebo.
Patients assigned rifaximin experienced significantly fewer hepatic encephalopathy events when compared with patients assigned placebo (21% vs. 36%; P=0.02). The total number of hepatic encephalopathy events were lower in those assigned the medication (n=35) when compared with those assigned placebo (n=57).
Further, there were 13 total hospitalizations in the rifaximin arm vs. 25 hospitalizations in the placebo arm. Ammonia levels in the blood were lower in patients assigned rifaximin versus placebo.
Among those not previously treated with the drug before enrollment, rifaximin decreased the number of patients with a hepatic encephalopathy event (10% vs. 32%; P<0.01), the time to a first event (HR=0.29; P<0.01) and the total number of events (7 vs. 31; P<0.01).
“Our findings provide evidence that elevated blood ammonia plays an important role in the development of hepatic encephalopathy,” Scharschmidt said. “Rifaximin reduced the risk for hepatic encephalopathy in patients with cirrhosis and further investigation of its therapeutic potential for patients with hepatic encephalopathy is warranted.”
“The study shows that [rifaximin] improves the outcome among cirrhotic patients with highly recurrent hepatic encephalopathy,” Juan Cordoba, MD, and Meritxell Ventura-Cots, MD, both of the Hospital Vall Hebron in Barcelona, Spain wrote in an accompanying editorial. “The new drug avoids the risk for sodium overload, was well tolerated and had a good safety profile.”
Disclosure: See study for full list of disclosures.