Intercept Pharmaceuticals' value jumped as much as 580% over two days in January following the unexpected announcement that it had stopped a trial of a liver disease drug because the drug's efficacy was so high. Shares in the 45-person, New York–based company soared when interim results with the drug obeticholic acid (OCA) for nonalcoholic steatohepatitis, which involves lipid accumulation in the liver, showed a highly statistically significant improvement. The Data and Safety Monitoring Board made the recommendation to halt the study after reviewing liver biopsy data from about half the 283 patients. “I don't think it was broadly known that there was going to be an interim look,” says James Molloy, managing director at Janney Montgomery Scott, pointing out that most early peeks at clinical trial data simply signal that the trial should continue. Patients that hadn't completed the trial were recorded as nonresponders in the intention-to-treat analysis, and the trial still registered a P-value of 0.0024 for the drug compared to placebo. “That's a fantastic result,” Molloy concluded. The analyst thinks the US Food and Drug Administration will still require another trial to approve OCA in this indication, but he believes part of the run-up in stock price came from the potential for OCA to be used off-label to treat fatty liver, which affects 2–5% of US citizens. Intercept's partner on the drug is Dainippon Sumitomo in Osaka, which is conducting a similar trial in Japan.