Lexicon To Present Results From LX9211 Phase 2 Trial In Postherpetic Neuralgia At The 2023 American Academy Of Neurology (AAN) Annual Meeting And The British Pain Society (BPS) 56th Annual Scientific Meeting 2023

Data accepted as AAN Late-Breaking AbstractTHE WOODLANDS Texas, April 21, 2023 (GLOBE NEWSWIRE) — Lexicon Pharmaceuticals, Inc. (Nasdaq: LXRX), today announced that results from RELIEF-PHN-1, a Phase 2 double-blind, placebo-controlled trial of its investigational drug LX9211 for the treatment of postherpetic neuralgia, will be presented during the Emerging Science session at the AAN Annual Meeting, April 22-27, in Boston, MA: RELIEF-PHN-1: A Phase 2 Double-Blind, Randomized, Placebo-Controlled Trial of LX9211 in the Treatment of Postherpetic Neuralgia Pain – an oral presentation and poster (004), Monday April 24, 11:33-11:39 a.m. ET, Boston Convention and Exhibition Center, presented by Anand Patel, MD, Conquest Research, Winter Park, FL Lexicon also announced that study investigators will present LX9211 clinical trial data at the BPS 56th Annual Scientific Meeting, May 9-11, in Glasgow, UK: Topline Results from RELIEF-PHN-1: A Phase 2 Double-Blind, Placebo-Controlled Trial of LX9211 in the treatment of Postherpetic Neuralgia Pain, Tuesday May 9, 4:05-5:05 p.m. BST, Glasgow, Scotland, UK, presented by Suma Gopinathan, PhD, Lexicon Pharmaceuticals, The Woodlands, TX Topline results from RELIEF-PHN-1 were announced in December 2022 providing further evidence of LX9211’s potential as an effective non-opioid treatment for neuropathic pain. LX9211 achieved significant and consistent benefits in the treatment of diabetic peripheral neuropathic pain in the RELIEF-DPN-1 study, from which full results were presented in November 2022. LX9211 has received Fast Track designation from the U.S. Food and Drug Administration for development in diabetic peripheral neuropathic pain. About the RELIEF-PHN-1 Study RELIEF-PHN-1 was a Phase 2 randomized, double-blind, placebo-controlled, parallel-group, multicenter study evaluating the efficacy and safety of LX9211 in the treatment of postherpetic neuralgia. The study enrolled 79 patients at 32 clinical sites. The primary efficacy endpoint under evaluation was the change from baseline (Day 1) to Week 6 in Average Daily Pain Score (ADPS), based on the 11- point numerical rating scale. About the RELIEF-DPN-1 Study RELIEF-DPN-1 was a Phase 2 randomized, double-blind, placebo-controlled, parallel-group, multicenter study evaluating the efficacy, safety, and pharmacokinetics of LX9211 in the treatment of diabetic peripheral neuropathic pain. The study enrolled 319 patients at 45 U.S. clinical sites, evaluating three treatment groups receiving placebo or one of two dosing regimens of LX9211 (an initial single dose of 100 mg followed by once-daily doses of 10 mg, or an initial single dose of 200 mg followed by once-daily doses of 20 mg). The primary efficacy endpoint under evaluation was the change from baseline to week 6 in ADPS, based on the 11-point numerical rating scale. The results of the study on the primary endpoint showed a reduction from baseline in ADPS of 1.39 points (p=0.007 versus placebo) in the low dose arm and 1.27 points (p=0.030 versus placebo) in the high dose arm, compared to 0.72 in the placebo arm. Under the statistical analysis plan for the study, a p-value of less than 0.028 was considered statistically significant. About LX9211 Discovered using Lexicon’s unique approach to gene science, LX9211 is a potent, orally delivered, selective small molecule inhibitor of adaptor-associated kinase 1 (AAK1). Lexicon identified AAK1 in its target discovery efforts as a promising approach for the treatment of neuropathic pain and identified LX9211 and another development candidate in a neuroscience drug discovery alliance with Bristol-Myers Squibb from which Lexicon holds exclusive development and commercialization rights. Preclinical studies of LX9211 demonstrated central nervous system penetration and reduction in pain behavior in models of neuropathic pain without affecting opiate pathways. LX9211 has received Fast Track designation from the U.S. Food and Drug Administration for the development in diabetic peripheral neuropathic pain. About Lexicon Pharmaceuticals Lexicon is a biopharmaceutical company with a mission of pioneering medicines that transform patients’ lives. Through its Genome5000™ program, Lexicon scientists studied the role and function of nearly 5,000 genes and identified more than 100 protein targets with significant therapeutic potential in a range of diseases. Through the precise targeting of these proteins, Lexicon is pioneering the discovery and development of innovative medicines to safely and effectively treat disease. Lexicon advanced one of these medicines to market and has a pipeline of promising drug candidates in discovery and clinical and preclinical development in heart failure, neuropathic pain, diabetes and metabolism and other indications.  For additional information, please visit www.lexpharma.com. Safe Harbor Statement This press release contains “forward-looking statements,” including statements relating to the research and clinical development of, regulatory filings for, and potential therapeutic and commercial potential of LX9211. In addition, this press release also contains forward looking statements relating to Lexicon’s financial position and long-term outlook on its business, 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 Lexicon’s ability to meet its capital requirements, successfully conduct preclinical and clinical development and obtain necessary regulatory approvals of sotagliflozin, LX9211 and its other potential drug candidates on its anticipated timelines, successfully commercialize any products for which it obtains regulatory approval, 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. Any of these risks, uncertainties and other factors 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 “Risk Factors” in Lexicon’s annual report on Form 10-K for the year ended December 31, 2022, 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. For Investor Inquiries: Carrie SiragusaLexicon Pharmaceuticals, [email protected] For Media Inquiries: Alina Cocuzza (Kolomeyer)Lexicon Pharmaceuticals, [email protected]