Synergy Pharma constipation drug succeeds mid-stage trial Wed Nov 19, 2014 9:17am EST (Reuters) - Synergy Pharmaceuticals Inc said its experimental drug for opioid-induced constipation was found safe and effective in a mid-stage trial. Synergy Pharmaceuticals shares were up 8 percent in premarket trading. The drug SP-333 showed statistically significant improvement in spontaneous bowel movement in the fourth week of treatment, compared with a placebo, the company said on Wednesday. The study was designed to evaluate the effect of a once-daily oral tablet against placebo in patients who had less than three spontaneous bowel movements per week and experienced constipation-related symptoms. Opioids are a class of drugs that are used to treat and manage pain. A common side effect associated with the use of these drugs are that they reduce the gastrointestinal tract's motility, making bowel movements difficult. Synergy said the experimental drug was found safe and well tolerated at all doses and it expects to evaluate the full dataset in the coming weeks. The company is also developing another constipation drug called Plecanatide which is currently in a late-stage trial. Reporting by Anjali Rao Koppala in Bangalore; Editing by Joyjeet Das