THE WOODLANDS, Texas, July 28, 2011 /PRNewswire/ -- Lexicon Pharmaceuticals, Inc. (Nasdaq: LXRX), a biopharmaceutical company focused on discovering breakthrough treatments for human disease, announced today that it has successfully completed a Phase 1 clinical trial of LX1033, an orally-delivered small molecule drug candidate for diarrhea-predominant irritable bowel syndrome (IBS-d). Lexicon plans to move LX1033 forward into a Phase 2 study in patients with IBS-d.
Top-line results demonstrated that LX1033 was well tolerated at all doses and produced a statistically significant reduction in serotonin synthesis compared to placebo, as measured by both plasma (p<0.001) and urinary (p<0.01) 5-hydroxyindoleacetic acid (5-HIAA), a biomarker for serotonin synthesis. Importantly, a greater reduction in serotonin synthesis was achieved with lower and less frequent dosing and at lower drug exposure levels than was observed with Lexicon's first generation serotonin synthesis inhibitor, LX1031, which had previously demonstrated clinical benefit to IBS patients in a Phase 2a clinical trial as measured by both global assessment of adequate relief and stool consistency.
"Based on the completed LX1033 Phase 1 program, we are confident that a convenient dose regimen of this compound can provide the level of serotonin reduction that we have previously associated with clinical benefit for patients with IBS-d," said Dr. Brian Zambrowicz, chief scientific officer at Lexicon. "We were also impressed by the performance of the blood test for measuring 5-HIAA and anticipate using this biomarker to guide future drug development of LX1033."
The LX1033 Phase 1 trial was conducted as a