Another mid-stage trial failure for emricasan, the caspase inhibitor at the heart of a multimillion-dollar NASH deal between developer Conatus Pharmaceuticals Inc. and Novartis AG, appears to have shaken investor confidence in the program's future, sending Conatus shares (NASDAQ:CNAT) down 56 percent to $1.28 on Friday. A shortfall on ENCORE-NF's primary endpoint, improvement in a measure of liver scarring, is the second setback in the collaboration following the drug's failure to meet the primary endpoint of a separate portal hypertension study.