TY - JOUR
T1 - LX-1031, a tryptophan 5-hydroxylase inhibitor that reduces 5-HT levels for the potential treatment of irritable bowel syndrome
AU - Camilleri, Michael
PY - 2010/12
Y1 - 2010/12
N2 - LX-1031, being developed by Lexicon Pharmaceuticals, is an oral, small-molecule tryptophan 5-hydroxylase (TPH) inhibitor that reduces 5-HT synthesis peripherally. LX-1031 is being developed for the potential treatment of diarrhea-predominant irritable bowel syndrome (IBS-D), which is characterized by excess 5-HT. In preclinical studies, LX-1031 dose-dependently reduced expression of 5-HT in the duodenum, jejunum and ileum, but had no effect on brain 5-HT levels. In ascending single-dose and multiple-dose (14 day) phase I clinical trials in healthy volunteers, LX-1031 significantly reduced urinary 5-hydroxyindoleacetic acid (5-HIAA; a marker of 5-HT metabolism) levels, starting by day 5 and persisting over the duration of exposure. In a phase II clinical trial in patients with IBS-D, a 1000-mg qid dose of LX-1031 was associated with improved weekly global scores and stool consistency, and lower urinary 5-HIAA levels over a 28-day treatment period. LX-1031 was well tolerated in trials to date. In conclusion, LX-1031 appears promising for IBS-D. Optimal doses, efficacy in IBS clinical trials and safety need to be fully elucidated.
AB - LX-1031, being developed by Lexicon Pharmaceuticals, is an oral, small-molecule tryptophan 5-hydroxylase (TPH) inhibitor that reduces 5-HT synthesis peripherally. LX-1031 is being developed for the potential treatment of diarrhea-predominant irritable bowel syndrome (IBS-D), which is characterized by excess 5-HT. In preclinical studies, LX-1031 dose-dependently reduced expression of 5-HT in the duodenum, jejunum and ileum, but had no effect on brain 5-HT levels. In ascending single-dose and multiple-dose (14 day) phase I clinical trials in healthy volunteers, LX-1031 significantly reduced urinary 5-hydroxyindoleacetic acid (5-HIAA; a marker of 5-HT metabolism) levels, starting by day 5 and persisting over the duration of exposure. In a phase II clinical trial in patients with IBS-D, a 1000-mg qid dose of LX-1031 was associated with improved weekly global scores and stool consistency, and lower urinary 5-HIAA levels over a 28-day treatment period. LX-1031 was well tolerated in trials to date. In conclusion, LX-1031 appears promising for IBS-D. Optimal doses, efficacy in IBS clinical trials and safety need to be fully elucidated.
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M3 - Article
C2 - 21154152
AN - SCOPUS:79952757904
SN - 1369-7056
VL - 13
SP - 921
EP - 928
JO - IDrugs
JF - IDrugs
IS - 12
ER -