Ocera Therapeutics of San Diego and the Hospital Universitari Vall d'Hebron Research Institute in Barcelona released preliminary data from an open label phase II study evaluating the overall effectiveness and safety of OCR-002 (ornithine phenylacetate) for the treatment of cirrhosis of the liver and upper GI bleeding.

Interim analysis of the first cohort of patients demonstrated that OCR-002, a novel injectable agent that removes toxic, circulating ammonia from the blood, is well tolerated and provided a rapid and durable ammonia reduction after 36 hours of treatment. By removing circulating ammonia, OCR-002 may treat or prevent hepatic encephalopathy (HE), a neuropsychiatric complication of acute liver failure associated with increased levels of circulating ammonia.

Furthermore, all 48 patients tolerated OCR-002 well for 5 days. There were no severe toxicities associated with the treatment and no incidence of HE, with patients doing well at the 30 day follow up. A rapid drop in ammonia from 80.01+/-13.44 uM at baseline to 41.95+/-4.99 uM was observed at 36 hours (ANOVA, p<0.05).

"Cirrhosis patients that present with acute upper gastrointestinal bleeding have a 30% chance of developing hepatic encephalopathy and require intensive care,” explained Dr. Juan Cordoba of Hospital Universitari Vall d'Hebron and the lead investigator of the study. “A medicine that can quickly remove the toxic ammonia may help prevent or reverse this life-threatening condition, minimize the need for intensive care and shorten hospitalization."

OCR-002, developed by Ocera Therapeutics, has received Orphan Drug designation in the U.S. and Europe and has Fast Track status in the U.S. OCR-002 is also being evaluated as a treatment of acute liver failure in the U.S.