Lexicon Completes Phase 2 Trial Of LX1033 In IBS-d - Quick Facts

(RTTNews) - Lexicon Pharmaceuticals Inc. (LXRX) reported top-line results from an initial Phase 2 trial exploring the use of LX1033 in diarrhea-predominant irritable bowel syndrome or IBS-d. LX1033 is an investigational drug that inhibits serotonin synthesis in the gastrointestinal tract. Serotonin is a neurotransmitter that has been shown to play a role in the symptoms of irritable bowel syndrome.

The primary endpoint was the change in stool consistency averaged from baseline to day 28, while the key secondary endpoint was the change from baseline in abdominal pain, and other endpoints included the change in plasma 5-HIAA. All treatment groups, including placebo, demonstrated significant improvements over time, yet differences between placebo and LX1033 in stool consistency were not statistically significant. The stool consistency data was further analyzed adjusting for early terminations which may have enhanced the placebo response rate.

In this Phase 2 trial of IBS-d, 373 patients were randomized to be treated for 28 days with either placebo or one of three different dose levels of LX1033 for 28 days, 1000 mg twice daily, 500 mg twice daily, and 500 mg three times daily.