(Corrects stock's Tuesday close in last paragraph to $4.38 from $4.69)
Feb 12 (Reuters) - Ventrus Biosciences Inc said its lead experimental drug to treat anal fissures failed to reduce pain more than a placebo in a late-stage trial, sending its shares plunging 67 percent in premarket trading.
In May 2012, the company had shown the treatment, codenamed VEN 307, was superior to a dummy drug for the same indication, in another late-stage trial.
Ventrus said on Wednesday that gastrointestinal disorders were the most common adverse events reported by the 434 patients in the study, which aimed to reduce anal pain associated with or following defecation.
An anal fissure is a tear in the lining of the anal canal characterized by severe pain associated with or after bowel movements.
Ventrus acquired the North American rights to VEN 307, also known as Diltiazem Hydrochloride 2% Cream, for the treatment of anal fissures from S.L.A. Pharma AG.
The drug, which has been used for decades to treat angina and hypertension, dilates the blood vessels supplying the region, substantially decreasing pain.
VEN 307, which is not approved to treat anal fissures, is currently listed in the U.S. anal fissure treatment guidelines as a preferred agent prior to attempting surgery, and is available only as a compounded medicine, the company said.
"While this second study confirms a consistent effect in decreasing (anal fissure) AF-related pain with Diltiazem 2%, results among placebo patients are inconsistent across these two pivotal studies", said Chief Executive Russell Ellison.
Ventrus plans to request a meeting with the U.S. Food and Drug Administration to determine the next steps in the path towards submitting a new drug application for the cream.
The New York-based company's shares were down at $1.41 in trading before the bell. They closed at $4.38 on the Nasdaq on Tuesday. (Reporting by Natalie Grover in Bangalore; Editing by Savio D'Souza)