THE WOODLANDS, Texas, Dec. 14, 2010 /PRNewswire-FirstCall/ -- Lexicon Pharmaceuticals, Inc. (Nasdaq: LXRX), a biopharmaceutical company focused on discovering breakthrough treatments for human disease, announced top-line results from a recently completed Phase 2a study of LX2931 in patients with rheumatoid arthritis (RA). LX2931 is an orally-delivered, small molecule drug candidate that inhibits sphingosine-1-phosphate (S1P) lyase, an enzyme important for modulating the immune system by controlling S1P levels in lymphoid tissues. The trial was the first test of this new anti-inflammatory mechanism of action in patients and was designed to obtain safety and tolerability information and signals of efficacy.
Results from the 12-week, randomized, double-blind, placebo-controlled study in 208 patients with RA demonstrated that all three doses tested, 70 mg, 110 mg, and 150 mg given once per day, were well tolerated over the 12-week treatment period. Taken together, the data also suggested that patients treated with 150 mg once daily of LX2931 showed an improvement in the primary efficacy endpoint, the percentage of patients achieving an American College of Rheumatology 20 (ACR20) response at week 12 (60% versus 49% for placebo). Patients treated with 70 mg or 110 mg once daily did not indicate improvement in the ACR20 at week 12 (44% and 41% response rates, respectively) relative to placebo. Adverse events for all three LX2931 dose groups were predominantly mild-to-moderate, with frequencies similar to the placebo group.
"We believe the preliminary signal of efficacy and the favorable safety profile observed in this trial supports further study of additional higher doses of LX2931 as an orally-delivered treatment for rheumatoid arthritis," said Dr. Arthur T. Sands, president and chief executive officer of Lexicon. "While we were disappointed by the unusually high placebo effect in this trial, we are encouraged by the excellent overall safety profile observed in the first test of this new mechanism of action in patients with RA."
The company intends to commence discussions with potential pharmaceutical partners to pursue further development of LX2931 in rheumatoid arthritis.
The recently completed study was a 12-week, randomized, double-blind, placebo-controlled study in 208 patients on stable dose methotrexate with progressing rheumatoid arthritis. Patients were randomized to receive either placebo (n=49) or LX2931, 70 mg (n=55), 110 mg (n=54), or 150 mg (n=50), once daily for 12 weeks. In addition to measurements to assess the drug's safety, efficacy endpoints included the primary endpoint, ACR20 at week 12, as well as secondary endpoints of ACR20, ACR50, ACR70 and DAS28 at weeks 4, 8 and 12. The trial was conducted at sites within the United States and Eastern Europe.
About S1P Lyase and the Role of S1P in Autoimmune Disease
S1P lyase is responsible for the irreversible degradation of S1P, a biologically active lipid that can act as a second messenger in signal transduction pathways important for immune function. Changes in local S1P concentrations and gradients in immune tissues can modify lymphocyte migration, inflammatory cell response, and affect barrier function of endothelial cells. Inhibiting S1P lyase results in an increase in S1P levels, primarily in lymphoid tissues. The physiological outcome of raising S1P levels in the lymphoid system is immune-modulation, which offers new opportunities for treating autoimmune and inflammatory diseases.
Lexicon is a biopharmaceutical company focused on discovering breakthrough treatments for human disease. Lexicon currently has four drug candidates in mid-stage development for diabetes, irritable bowel syndrome, carcinoid syndrome and rheumatoid arthritis, all of which were discovered by Lexicon's research team. Lexicon has used its proprietary gene knockout technology to identify more than 100 promising drug targets. Lexicon has focused drug discovery efforts on these biologically-validated targets to create its extensive pipeline of clinical and preclinical programs.
In addition to LX2931, Lexicon has three other drug candidates progressing through Phase 2 clinical trials: LX4211, an orally-delivered, once-daily, dual inhibitor of sodium glucose transporter 1 (SGLT1) and SGLT2 for type 2 diabetes; LX1031, a locally-acting serotonin synthesis inhibitor for irritable bowel syndrome; and LX1032, a peripherally-available serotonin synthesis inhibitor for carcinoid syndrome. For additional information about Lexicon and its programs, please visit www.lexpharma.com.
Safe Harbor Statement
This press release contains "forward-looking statements," including statements relating to the characterization of the safety profile of LX2931 observed in the Phase 2 clinical trial as favorable, the characterization of the results of the Phase 2 clinical trial of LX2931 as demonstrating a preliminary signal of efficacy and supporting further study as a potential treatment for rheumatoid arthritis, the mechanism of action of LX2931, and the potential therapeutic and commercial potential of LX2931 generally. 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, 2009, 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.
SOURCE Lexicon Pharmaceuticals, Inc.