Lexicon Pharmaceuticals recently announced their new drug LX1033 passed Phase I drug safety trials allowing it to move forward into Phase II testing.

Lexicon Pharmaceuticals’ LX1033 is a Irritable Bowel Syndrome drug meant for those with diarrhea predominant Irritable Bowel Syndrome symptoms or mixed symptoms that include diarrhea. LX1033 works by targeting the hydroxylase enzyme which is also known as TPH. TPH is essential for the production of serotonin within the body & it comes in two forms TPH1 & TPH2. TPH1 lives mainly in the digestive system, while TPH2 lives in the nervous system & the brain. LX1033 specifically targets TPH1 only & leaves TPH2 alone to avoid nervous system or psychoactive effects. Serotonin levels do seem to play a role in Irritable Bowel Syndrome, but how much is not fully understood.

LX1033 is actually more potent & targeted form of Lexicon Pharmaceuticals’ earlier drug LX1031. LX1031 made it to Phase IIa trials, which is usually where they trying to determine effective dosage levels. It would appear they felt they could do better than the results LX1031 was achieving & thus reintroduced it as LX1033. LX1033 appears to be more effective at the same dosage levels of LX1031.

Lexicon Pharmaceuticals’ plans to pursue Phase II trials soon.