Lexicon Pharmaceuticals’ Phase II clinical trial of the tryptophan hydroxylase inhibitor LX1031 in patients with non-constipating irritable bowel syndrome (IBS) has demonstrated positive results.

In the study, LX1031 was well tolerated and showed improvements in a global assessment of adequate relief from IBS pain and discomfort and in stool consistency.

The findings from the data were published in the August 2011 edition of scientific journal Gastroenterology.

In a recent Phase I study, LX1033 also demonstrated reductions in the 5-HIAA biomarker in healthy volunteers compared to those seen with LX1031, but with lower and less frequent dosing.