BALLERUP, Denmark I December 14, 2021 I LEO Pharma A/S, a global leader in medical dermatology, today announced it has enrolled the first patient in a Phase 2b dose-ranging clinical trial with an investigational oral histamine receptor 4 (H4R) antagonist (LEO 152020) for the potential treatment of adults with moderate-to-severe atopic dermatitis (AD).

Histamine is a key mediator of allergic inflammation.i Unlike histamine receptors 1-3, H4R plays a role in itch response and triggers the migration of cells in the immune system toward inflammatory and allergic sites throughout the body.ii,iii,iv As an oral H4R antagonist, LEO 152020 has the potential to prevent histamine-induced initiation of inflammatory and itch mechanisms via the histamine 4 receptor.v

The primary objective for the randomized, triple-blind, placebo-controlled, multi-center Phase 2b dose-ranging clinical trial is to evaluate the efficacy of LEO 152020 compared with placebo in the treatment of adults with moderate-to-severe The primary endpoint of the trial is change in Eczema Area and Severity Index (EASI) from baseline to Week Additional exploratory endpoints will evaluate patient-reported symptoms such as itch and The number of treatment-emergent adverse events per patient from baseline to Week 16 defines the key safety endpoint of the

“Managing a skin disease such as atopic dermatitis with oral treatments is challenging because of limited available options for chronic use,” said Prof. Dr. med. Thomas Werfel, Dept. Dermatology and Allergy, Hannover Medical School, Hannover, Germany, and lead investigator of the Phase 2b clinical trial. “This trial will evaluate whether an alternative oral option can potentially offer a new choice for adult patients with moderate-to-severe AD.”

AD is a chronic, inflammatory, skin disease characterized by intense itch and eczematous lesions.vii AD is the result of skin barrier dysfunction and immune dysregulation, leading to chronic inflammation.viii

“We have been encouraged by results on itch in pre-clinical studies with this investigational medicine for patients who prefer oral treatment options,” said Dr. Jörg Möller, Executive Vice President, Global Research & Development, LEO Pharma. “We are committed to developing innovative therapies that may help improve the lives of patients who need a wider range of treatment options and routes of administration for skin diseases.”


About LEO 152020
In 2018, LEO Pharma A/S and JW Pharmaceutical Corporation entered into a license agreement in which LEO Pharma gained exclusive rights to develop and commercialize LEO 152020 (LP0190/JW1601) for all non-ophthalmic indications worldwide, except in South Korea, where JW Pharmaceutical retains rights.

About LEO Pharma
LEO Pharma helps people achieve healthy skin. The company is a leader in medical dermatology with a robust R&D pipeline, a wide range of therapies and a pioneering spirit. Founded in 1908 and owned by the LEO Foundation, LEO Pharma has devoted decades of research and development to advance the science of dermatology, setting new standards of care for people with skin conditions. LEO Pharma is headquartered in Denmark with a global team of 6,000 people, serving 93 million patients in 130 countries. In 2020, the company generated net sales of DKK 10,133 billion.
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ii Thurmond RL. Frontiers Pharmacol. 2015;6:65.

iii Schaper‐Gerhardt K, et al. Br J Pharmacol. 2020;177:490-502.

iv Damaj BB, et al. J Immunol. 2007;179:7907-15.

v de Esch IJ et al. Trends Pharmacol Sci 2005;26:462-469.

vi ClinicalTrials.Gov: (Accessed November 2021).

vii Weidinger S, et al. Lancet. 2016; 387:1109-1122.

viii Boguniewicz M, et al. Immunol Rev. 2011;242(1):233-46.