* New Small Molecule Drug Candidate for Rheumatoid Arthritis and
Other Autoimmune Diseases
* Novel Mechanism of Action of Immune Modulation Shows Activity in
Human Studies
* LX2931 to Progress to Next Stage of Clinical Development in
Patients
THE WOODLANDS, Texas, Oct. 25, 2008 (GLOBE NEWSWIRE) -- Lexicon Pharmaceuticals, Inc. (Nasdaq:LXRX), a biopharmaceutical company focused on discovering and developing breakthrough treatments for human disease, will be presenting results at the American College of Rheumatology annual meeting from its Phase 1 clinical trials of LX2931. Lexicon will also be presenting results from its preclinical research demonstrating activity of LX2931 in models of rheumatoid arthritis and inflammation. LX2931 is an orally-delivered, small molecule drug candidate that has successfully completed Phase 1 testing in normal volunteers. Lexicon is planning to progress LX2931 into a drug-drug interaction study in rheumatoid arthritis patients who are also taking methotrexate, a standard therapy.
In the recently completed Phase 1b multiple ascending-dose trial, LX2931 was well tolerated at all doses, including the maximum dose of 150 mg per day, over the seven day dosing period. Results from this trial demonstrated a dose-dependent reduction in circulating lymphocytes, confirming the mechanism of action of LX2931 in regulating lymphocyte trafficking. The lymphocyte reductions observed in the multiple dose study are similar to those associated with a beneficial response obtained in animal models of arthritis after treatment with LX2931.
"We continue to be encouraged that multiple doses of LX2931 were well tolerated and produced a dose-dependent reduction in lymphocytes consistent with levels at which our results in animal models predict disease modifying activity," said Philip M. Brown, M.D., J.D., senior vice president of clinical development at Lexicon.
About the Clinical Trials
The Phase 1b trial was a randomized, double-blind, placebo controlled, multiple ascending-dose study assessing the safety, tolerability, and pharmacokinetics of LX2931 in 47 healthy volunteers. Five dose levels of LX2931, ranging from 25 mg to 150 mg, were assessed over seven days of dosing. LX2931 was well tolerated and produced a dose-dependent reduction in circulating lymphocytes, with rapid recovery following discontinuation of dosing. All adverse events were non-serious and were distributed across subjects in each dose group and the placebo group.
Lexicon also completed an additional placebo controlled, single ascending-dose escalation study assessing the safety, tolerability, and pharmacokinetics of LX2931 in 32 healthy volunteers. Four dose levels of LX2931, ranging from 175 mg to 250 mg were evaluated. LX2931 produced a dose-dependent decrease in absolute lymphocyte counts with maximal effect correlating with a plateauing of systemic exposure at 125 mg. A single subject in the 250 mg dose cohort developed acute abdominal pain which required treatment and resolved within 24 hours. A transient increase in hepatic transaminase levels was also observed in this subject. This event was similar to an event observed in the initial Phase 1 single ascending-dose study at 180 mg.
About the Target
Lexicon has previously shown that genetically "knocking out" or "knocking down" the target of LX2931, sphingosine-1-phosphate (S1P) lyase, substantially reduces the number of circulating lymphocytes, modulating the immune response in multiple animal models of autoimmune disease. Importantly, LX2931 has demonstrated pharmacology in preclinical and clinical studies consistent with the original observations in knockout animals.
About the Disease
Lymphocytes are a type of white blood cell that play an important role in the immune system. Inappropriate activation of lymphocytes is often associated with autoimmune diseases, a spectrum of disorders in which the immune system malfunctions and causes the body to attack its own organs, tissues and cells. Rheumatoid arthritis is an autoimmune disorder characterized by stiffness, pain, swelling, and limitation of motion in multiple joints. More than 2 million Americans suffer from rheumatoid arthritis, which, if left untreated, can result in disfigurement and disability from irreversible joint damage. According to the National Institutes of Health, autoimmune disorders affect between 14.7 and 23.5 million people in the United States.
About Lexicon
Lexicon is a biopharmaceutical company focused on discovering and developing breakthrough treatments for human disease. Lexicon currently has six drug candidates in development for autoimmune disease, carcinoid syndrome, cognitive disorders, diabetes, glaucoma and irritable bowel syndrome, all of which were discovered by the company's research team. The company is using its proprietary gene knockout technology to characterize approximately 5,000 genes in its Genome5000(tm) program, and has discovered more than 100 promising drug targets. Lexicon has applied small molecule chemistry and antibody technology to these biologically-validated targets to create its extensive pipeline of clinical and preclinical programs. Lexicon's goal is to advance 10 drug candidates into human clinical trials by the end of 2010, the strategic objective of its 10TO10 program. For additional information about Lexicon and its programs, please visit www.lexpharma.com.
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Safe Harbor Statement
This press release contains "forward-looking statements," including statements relating to Lexicon's clinical development of LX2931 and the potential therapeutic and commercial potential of LX2931. This press release also contains forward-looking statements relating to Lexicon's growth and future operating results, discovery and development of products, strategic alliances and intellectual property, as well as other matters that are not historical facts or information. All forward-looking statements are based on management's current assumptions and expectations and involve risks, uncertainties and other important factors, specifically including those relating to Lexicon's ability to successfully conduct clinical development of LX2931 and preclinical and clinical development of its other potential drug candidates, advance additional candidates into preclinical and clinical development, obtain necessary regulatory approvals, achieve its operational objectives, obtain patent protection for its discoveries and establish strategic alliances, as well as additional factors relating to manufacturing, intellectual property rights, and the therapeutic or commercial value of its drug candidates, that may cause Lexicon's actual results to be materially different from any future results expressed or implied by such forward-looking statements. Information identifying such important factors is contained under "Factors Affecting Forward-Looking Statements" and "Risk Factors" in Lexicon's annual report on Form 10-K for the year ended December 31, 2007, as filed with the Securities and Exchange Commission. Lexicon undertakes no obligation to update or revise any such forward-looking statements, whether as a result of new information, future events or otherwise.