Raptor's RP103 fails in mid-stage liver disease trial

Shares of US biotech firm Raptor Pharmaceutical (Nasdaq: RPTP) tanked 38.7% in late morning trading, after the company released top-line results from the Phase IIb CyNCh study, which did not meet its primary endpoint of improving non-alcoholic steatohepatitis (NASH) in children.

The trial evaluated the safety and efficacy of RP103, or cysteamine bitartrate delayed-release capsules, in children with biopsy-confirmed NASH. The study did not achieve its primary endpoint defined as a two-point decrease in NAFLD Activity Score (NAS) and no worsening of fibrosis (p-value = 0.34). There were no differences in adverse events observed in children on RP103 compared to placebo.

Will likely not advance the program