MORRISVILLE, NC (TheStreet) -- An experimental drug from Furiex Pharmaceuticals (FURX) produced more "consistent" stool and reduced pain compared to a placebo in two large, phase III studies of patients diagnosed with a form of irritable bowel syndrome that causes excessive diarrhea, the company said Tuesday.
Furiex shares soared at Tuesday's open, rising 147% to $113.94.
Furiex will submit the drug, eluxadoline, for U.S. approval at the end of the second quarter based on the positive results from the two studies. A European approval filing will likely be submitted in 2015.
Eluxadoline is designed to work like the opioid painkiller oxycodone except with low oral bioavailability and only in the gut, where it can treat diarrhea and reduce pain without causing constipation.
Furiex conducted two identical phase III studies which enrolled 2,428 patients with diarrhea-predominant irritable bowel syndrome (IBS-d). The primary endpoint of the studies was a composite response which required patients to report both improvement in stool consistency and reductions in abdominal pain.
FDA mandated that Furiex demonstrate a treatment benefit favoring eluxadoline over placebo for 12 weeks, while European regulators wanted to see a treatment benefit lasting 26 weeks.
In the first study, IBS-d patients treated with two different doses of eluxadoline -- 75 mg and 100 mg -- both responded better than placebo at 12 and 26 weeks. The benefit favoring eluxadoline was statistically significant.
In the second study, both doses of eluxadoline were numerically and statistically superior to placebo at the FDA-mandated 12 week time point, but at 26 weeks, only the higher 100 mg dose of eluxadoline was better than placebo. The lower dose of Furiex's drug was numerically better than placebo but not by enough to reach statistical significance.