** U.S.-listed shares of drugmaker Bausch Health Companies BHC.TO fall 4.1% to $6.30 premarket
** Co says its brain dysfunction treatment failed to meet the main goal in two late-stage trials
** Co was testing a new version of its antibiotic, rifaximin, in patients with liver scarring to prevent hepatic encephalopathy, a condition where the liver does not filter toxins, impairing brain function as a result
** "We are currently reviewing the full dataset to determine potential new development opportunities," BHC says
** Up to stock's last close, BHC declined 13.8% over the past year
(Reporting by Sneha S K)
((Sneha.SK@thomsonreuters.com;))