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June 17 (Reuters) - Synergy Pharmaceuticals Inc said its drug for idiopathic constipation met the main goal in a late-stage trial, sending its shares up 56 percent in premarket trade on Wednesday.
Plecanatide, Synergy's lead experimental drug, mimics a hormone that promotes fluid secretion in the gastrointestinal tract, allowing for normal bowel function.
More patients consistently responded to the treatment, which was tested at two dosage strengths, than to a placebo, the company said.
Data showed that the drug was safe and effective, with about 1 percent of patients in the study experiencing serious adverse events, the most common of which was diarrhea, the company said.
Idiopathic constipation affects about 15 percent of the U.S. population, according to the National Institutes of Health. It is called idiopathic because the cause of this type of constipation is unknown and it is not caused by underlying illness or medication.
Only two drugs are currently approved to treat the condition, Sucampo Pharmaceuticals Inc and Takeda Pharmaceutical Co Ltd's Amitiza and Allergan Plc's Linzess.
Amitiza raked in sales of about $331.6 million in 2014, while Linzess racked up sales of $297 million.
Synergy said it plans to apply for regulatory approval in the fourth quarter.
Shares of the New York-based company were trading at $7.58 before the bell on Wednesday. The stock closed at $4.64 on the Nasdaq on Tuesday.
(Reporting by Amrutha Penumudi and Samantha Kareen Nair in Bengaluru; Editing by Joyjeet Das and Simon Jennings)