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Escient Pharmaceuticals Initiates Phase 2 PACIFIC Study Evaluating EP547, An Oral MRGPRX4 Antagonist, in Subjects with Cholestatic Pruritus

SAN DIEGO, Calif., November 17, 2022 – 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 the initiation of a Phase 2 clinical study of EP547 in subjects with cholestatic pruritus.

EP547 is a highly selective antagonist of MRGPRX4, a cell surface receptor expressed on sensory neurons that is activated by bile acids, bilirubin and other heme metabolites and thought to be a key mediator of the often intense itch experienced by patients with cholestatic liver disease.

The Phase 2 study, PACIFIC, is a randomized, double-blind, placebo-controlled study designed to assess the efficacy, safety and tolerability of EP547 in subjects with cholestatic pruritus due to primary biliary cholangitis (PBC) or primary sclerosing cholangitis (PSC).

“Intense, unrelenting itch is a common and often debilitating symptom for people living with PBC, PSC and other cholestatic liver diseases. There remains a large unmet need for safe and more efficacious treatments,” said Gideon Hirschfield, FRCP, PhD, Chair in Autoimmune Liver Disease Research, Professor, Division of Gastroenterology and Hepatology, University of Toronto, and a lead investigator of the PACIFIC study. “Accumulation of bile acids and other bile components in the skin has long been implicated as a potential cause of cholestatic pruritus, and blocking the activation of sensory itch neurons by bile acids with EP547 thus represents a promising, mechanistically targeted therapeutic approach. It really is quite exciting and innovative to be testing the concept that cholestatic itch is in part a neurosensory-inflammatory process.”

“Building upon the excellent safety, tolerability and PK profile of EP547 in our previously completed Phase 1 study, we are excited to initiate the Phase 2 PACIFIC study, designed to establish definitive clinical proof-of-concept of MRGPRX4 antagonism in cholestatic pruritus,” said Christian Weyer, MD, President and Chief Medical Officer at Escient Pharmaceuticals. “While the initial focus of our clinical program is focused on PBC and PSC, we believe EP547 has broad potential as a targeted anti-pruritic treatment for other forms of intra- and extrahepatic cholestasis.”

The Phase 2 PACIFIC study will enroll approximately 58 patients with moderate-to-severe pruritus due to PBC or PSC. The study comprises a 6-week double-blind treatment period in which subjects are randomized 1:1 to 100mg EP547 or placebo, dosed orally once daily, followed by a 6-week open label extension period in which all subjects receive EP547. The primary efficacy endpoint is the change from baseline to week 6 in itch intensity.

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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.