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Escient Pharmaceuticals Announces IND Clearance by FDA to Start Phase 1 Study of EP262, a First-in-Class Oral MRGPRX2 Antagonist for Mast Cell Mediated Disorders

SAN DIEGO, Calif., January 30, 2023 — Escient Pharmaceuticals, a clinical-stage company advancing novel small molecule therapeutics for the potential treatment of a broad range of neurosensory-inflammatory disorders, today announced that the U.S. Food and Drug Administration (FDA) has cleared the company’s Investigational New Drug (IND) application for EP262, enabling the initiation of a Phase 1 first-in-human study for the company’s second drug candidate to be advanced into clinical development.

EP262 is a first-in-class, potent, highly selective small molecule antagonist of MRGPRX2, a receptor mediating non-IgE driven mast cell degranulation. By blocking activation of MRGPRX2 and degranulation of mast cells, EP262 has the potential to effectively treat a broad range of mast cell mediated diseases with an initial focus on chronic urticarias (hives) and atopic dermatitis (eczema). EP262 represents a novel, targeted approach to the treatment of these disorders with the potential for once-daily oral administration without the serious side effects observed with other approaches.

“There is growing evidence that MRGPRX2 plays an important role in the pathogenesis of many diseases, as a key mediator of mast cell degranulation and neurogenic and eosinophilic inflammation,” commented Christian Weyer, MD, President and Chief Medical Officer at Escient Pharmaceuticals. “Advancement of EP262 into the clinic marks an important milestone for Escient and for the field as it paves the way for clinical investigations aimed at elucidating and harnessing the therapeutic potential of this novel target.”

Escient plans to conduct a Phase 1 study in the first half of 2023 to evaluate the safety, tolerability and pharmacokinetics of EP262 in healthy volunteers. Following this study, in the second half of 2023, the company plans to initiate several clinical proof-of-concept studies evaluating EP262 in patients with chronic inducible urticaria, chronic spontaneous urticaria, and atopic dermatitis.


Mas-related G protein-coupled receptor X2 (MRGPRX2) is a receptor expressed on mast cells found in barrier tissues (e.g. skin, airways, gastrointestinal tract) that is activated by numerous ligands, including many peptides released from sensory neurons as well as other cell types. In response to MRGPRX2 activation, mast cells degranulate and release histamine, tryptase, chymase, chemokines and cytokines, which can cause itchy hives, angioedema, type 2 inflammation (through engagement of the adaptive immune system) and chronic pruritus and pain.

About Escient Pharmaceuticals

Escient Pharmaceuticals is a clinical-stage company focused on developing novel therapeutics to address a broad range of neurosensory-inflammatory disorders. The company’s pipeline includes two first-in-class small molecule antagonists targeting MRGPRX2 for the treatment of various mast cell mediated disorders and MRGPRX4 for cholestatic pruritus. Based in San Diego, California, Escient is led by an experienced management and scientific team and funded by top-tier life science investors.

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Aaron Mishel
Chief Financial Officer
Escient Pharmaceuticals, Inc.