LG710
Irritable Bowel Syndrome (IBS)
Lexicon’s LX1031 drug candidate is intended to reduce IBS symptoms by decreasing the production of non-neuronal (peripheral) serotonin
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Tryptophan hydroxylase (TPH), found in enterochromaffin (EC) cells of the gastrointestinal (GI) tract, is a key enzyme in the production of serotonin. |
About the Disease
IBS is a common disorder characterized by abdominal pain, cramping, and changes in bowel function. It is classified according to three categories:
- IBS-c: Constipation
- IBS-d: Diarrhea
- Mixed: Multiple symptoms
About the Market
IBS is estimated to affect up to 20% of the U.S. population, or between 25-45 million U.S. residents. It is the most common diagnosis made by gastroenterologists, and is one of the disorders most frequently treated by primary care physicians.
The treatment market for any disease that affects one in five Americans is significant. For instance, in 2006 the top selling drugs used to treat IBS by targeting the serotonin pathway accounted for over $500 million in sales (Lotronex and Zelnorm).
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Tryptophan hydroxylase (TPH), found in enterochromaffin (EC) cells of the gastrointestinal (GI) tract, is a key enzyme in the production of serotonin. |
The Lexicon Solution
Current drugs targeting the serotonin pathway for IBS affect the various serotonin receptor subtypes. Lexicon’s unique gene knockout research (see Genome5000 project) has revealed a new mechanism for targeting the serotonin pathway (for IBS), by targeting TPH, a key enzyme in serotonin production in the GI tract. In preclinical studies, treatment with LX1031 reduced serotonin levels in the GI tract in multiple species.