LX9211 demonstrated clear evidence of effect, achieving Lexicon’s goal for the study of supporting advancement in another indication within neuropathic pain

Consistent reduction in ADPS compared to placebo throughout dosing period, statistically significant when measured across dosing period, but not reaching significance at Week 6 primary endpoint

Adverse event profile consistent with that observed in prior Phase 2 study

THE WOODLANDS, TX, UA I December 21, 2022 I Lexicon Pharmaceuticals, Inc. (Nasdaq: LXRX) today announced topline results of RELIEF-PHN-1, its Phase 2 proof-of-concept study of LX9211 in postherpetic neuralgia. LX9211 achieved a reduction in average daily pain score (ADPS) of 2.42 from baseline at week 6 compared to a reduction of 1.62 in the placebo arm, with a placebo adjusted difference of 0.80 (p=0.12). Although these results did not reach statistical significance on the primary endpoint of the study, overall study results demonstrated clear evidence of effect. Separation of LX9211 from placebo on ADPS was seen at week 1 and maintained consistently thereafter, with an average placebo adjusted reduction over the 6 Week dosing period of 0.80 (p=0.03).

A photo accompanying this announcement is available at https://www.globenewswire.com/NewsRoom/AttachmentNg/d64d9848-3c4c-43a5-a8d6-09b3b7123b6f

“These results in postherpetic neuralgia achieve our goal for this small, 79-patient study of establishing clear evidence of effect supporting the further development of LX9211 in another neuropathic pain condition,” said Craig Granowitz, M.D., Ph.D., Lexicon’s senior vice president and chief medical officer. “The RELIEF-PHN-1 study results are broadly consistent with the results achieved in our positive Phase 2 study of LX9211 in painful diabetic neuropathy (RELIEF-DPN-1) which enrolled over 300 patients. These results bolster our confidence in moving the LX9211 clinical program forward in hopes of delivering a potential solution for neuropathic pain patients in need of additional treatment options.”

Notably, the study included only the higher of the two doses evaluated in RELIEF-DPN-1. The lower dose arm (100 mg on Day 1 and 10 mg thereafter) in RELIEF-DPN-1 demonstrated statistically significant results on ADPS and meaningfully better tolerability than the higher (200 mg on Day 1 and 20 mg thereafter) dose.

Adverse events observed were consistent with previous studies, with dizziness as the most commonly reported and the most frequently associated with patient dropouts from the study. There were no serious adverse events or deaths reported in the study.

A full analysis of the results from RELIEF-PHN-1 will be submitted for publication at an upcoming medical conference and in a peer-reviewed journal.

LX9211 achieved significant and consistent benefits in the treatment of painful diabetic neuropathy 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 Today’s Live Conference Call and Webcast

Lexicon management will host a live conference call and webcast at 5:00 pm ET to discuss the study results. The dial-in number for the conference call is 1-888-317-6003 and the conference ID for all callers is 2304275. The live webcast and replay may be accessed by visiting Lexicon’s website at www.lexpharma.com/events. An archived version of the webcast will be available on the website for 14 days.

About the RELIEF-PHN-1 Study

RELIEF-PHN 1 is a Phase 2 randomized, double-blind, placebo-controlled, parallel-group, multicenter study evaluating the efficacy, safety and pharmacokinetics of LX9211 in the treatment of post-herpetic 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 painful diabetic neuropathy, also referred to as 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.

SOURCE: Lexicon Pharmaceuticals