(Adds share movement)
By Bill Berkrot
Feb 4 (Reuters) - Shares of Furiex Pharmaceuticals Inc more than doubled in value after the company said its experimental drug significantly alleviated diarrhea and abdominal pain associated with irritable bowel syndrome in two large late-stage trials.
Furiex said it would apply by mid-year for U.S. approval of the drug, eluxadoline, to treat diarrhea-predominant irritable bowel syndrome (IBS-d), a debilitating bowel disorder that affects about 28 million people in the United States and major European markets.
Furiex said it expected to seek European approval in early 2015.
The company's shares rose as much as 165 percent to $121.97, valuing it at about $1.3 billion.
"We believe that there are a lot of patients out there who need this drug. There is a huge unmet need," Furiex Chief Medical Officer June Almenoff said in a telephone interview.
Currently approved drugs for IBS address constipation associated with the disorder, but there are few options for diarrhea predominant IBS.
Furiex founder and chairman Fred Eshelman said he believes the drug has the potential for blockbuster sales, which he defined as annual sales of between $750 million and $1 billion.
Eluxadoline was tested at two doses against a placebo over the course of 12 weeks to meet requirements by the U.S. Food and Drug Administration, and for 26 weeks for European health regulators, in Phase III studies involving 2,428 patients, Furiex said.
For the combined goal of improvement in abdominal pain and stool consistency for at least half the days in the study, eluxadoline achieved a statistically significant improvement at the 100 milligram and 75 mg doses through 12 weeks in both studies.
On the 26-week measure, the higher dose succeeded in both studies but the lower dose missed statistical significance in one of the two trials, according to initial results released by the company.
The success appeared to be driven by the percentage of patients reporting improvements in diarrhea, which ranged from 30 percent to 37 percent versus 22 percent and 20.9 percent for the placebo groups.
When the composite goal was broken into its two components, researchers found a numerical improvement in pain response rates that did not achieve statistical significance.
The drug appeared to be safe and well-tolerated in both studies, Furiex said. The most commonly reported side effects were constipation and nausea.
The company plans to present a far more detailed analysis of the late stage studies at an upcoming medical meeting.
"We're very excited about the path ahead and about how this can transform patients' lives," Almenoff said.
Furiex shares were up 142 percent at $110.99 in early trading on the Nasdaq. (Reporting by Bill Berkrot in New York; editing by Matthew Lewis)