Sojournix Presents Data at NAMS Showing SJX-653 Exhibits Potent NK3 Antagonist Profile Across Nonclinical and Initial Clinical Studies in Men and Postmenopausal Women
“The progression of SJX-653 into clinical studies enabled a translational assessment of the exposure/response relationship across in vitro models, in vivo studies in guinea pigs and dogs, and clinical studies in men and postmenopausal women,” said Phil Graham PhD, Chief Development Officer at Sojournix. “The high in vitro potency of SJX-653 translated with remarkable consistency across these studies, with plasma concentrations in the range of 10 ng/mL exhibiting pharmacological or pharmacodynamic effects indicative of central NK3 receptor antagonism.”
Data highlights from the NAMS poster include:
- SJX-653 is a competitive antagonist with an in vitro affinity for the human NK3 receptor of 4.3 nM and corresponding IC50 for functional antagonism of 9.0 nM
- The high in vitro potency of SJX-653 translates across in vivo models and initial clinical studies using established pharmacological or pharmacodynamic measures of NK3 antagonism, including reductions in luteinizing hormone (LH) in postmenopausal women, reductions in LH and testosterone (T) in men, and reductions in T in male dogs
- In postmenopausal women, 4.5 mg SJX-653 significantly reduced LH (p=0.018 vs placebo) with a maximum effect at 2 hours and corresponding plasma levels in the range of 10 ng/mL
- The moderate protein binding and good brain penetration of SJX-653 likely contribute to the robust translation of SJX-653 potency across experimental models and human studies
- SJX-653 demonstrated a pharmacokinetic profile supportive of once-daily (QD) dosing, with a half-life of 12-13 hours in men and postmenopausal women
SJX-653 is a novel, potent, and selective neurokinin 3 (NK3) antagonist in Phase 2 clinical development as a non-hormonal once-daily (QD) therapy for moderate to severe vasomotor symptoms (VMS) due to menopause. NK3 antagonism is a clinically and genetically validated new approach for treating menopausal hot flashes. During menopause, declining estrogen levels lead to an over-production of neurokinin B (NKB), an endogenous neuropeptide that binds to and activates NK3 receptors. By reducing the excessive signaling of NKB through NK3 receptors in the hypothalamic area of the brain that regulates heat dissipation, SJX-653 is expected to alleviate vasomotor symptoms due to menopause.
About Vasomotor Symptoms (VMS)
Vasomotor symptoms (VMS), or hot flashes, are sudden sensations of intense heat, sweating, and skin reddening that can occur frequently in menopausal women. VMS occur both during the day and night, disrupting daily activities and sleep, and are associated with increased rates of insomnia, depression, and cognitive impairment. More than 2 million women in the United States enter menopause each year and the majority experience VMS, with symptoms typically persisting for many years during and after menopause. Current treatment options are limited to hormone therapy, which patients and physicians often avoid due to safety concerns, or non-hormonal agents known to have limited efficacy. There is a significant unmet medical need for a new non-hormonal approach.
Sojournix is a clinical-stage biopharmaceutical company dedicated to developing and commercializing transformative new medicines for the treatment of women’s health and neuroendocrine disorders. The company is developing SJX-653, a novel, potent, selective neurokinin 3 (NK3) antagonist as a non-hormonal once-daily therapy for moderate to severe vasomotor symptoms (commonly called hot flashes) due to menopause. NK3 antagonism is a clinically and genetically validated new approach to treating menopausal hot flashes that targets the excessive signaling of neurokinin B through NK3 receptors in the hypothalamic area of the brain that regulates heat dissipation. To learn more about Sojournix, please visit www.sojournixpharma.com.