Efficacy and Safety of LEO 152020 Tablets for the Treatment of Adults With Moderate to Severe Atopic Dermatitis

Phase 2

Completed

Brief Summary: This is an up to 22-week clinical study in adult participants with moderate to severe atopic dermatitis (AD).

The purpose of the study is to test a new tablet (LEO 152020) to see if it improves AD and what the side effects are when compared with a placebo tablet with no medical ingredient.

During the study, there will be a 16-week treatment period during which the participants will be asked to take the tablets. The participants will regularly visit the clinic for tests and the study doctor will evaluate their AD. The participants will also be asked to answer questions about their AD symptoms, itch, sleep, and quality of life.

Recruitment & Eligibility

Inclusion Criteria

Adult, age 18 years or older at screening.
Diagnosis of chronic atopic dermatitis (AD).
History of AD ≥1 year prior to baseline.
Recent (within 6 months prior to baseline) documented history of inadequate response to topical AD treatments or subject for whom topical AD treatments are medically inadvisable.
7.1≤ Eczema Area and Severity Index (EASI) ≤50 at baseline.
Validated Investigator Global Assessment Scale for Atopic Dermatitis (vIGA-AD) score ≥3 at baseline.

Exclusion Criteria

Previous treatment with an oral histidine 4 receptor (H4R) antagonist (including LEO 152020) within 6 months prior to baseline.
Previous treatment with 3 or more systemic AD treatments prior to screening.
Women who are pregnant, intend to become pregnant, or are lactating.

Arm && Interventions

Group	Intervention	Description
LEO 152020 tablet - Dose regimen 1	LEO 152020 tablet	Participants will be asked to take tablets from Week 0 to Week 16 (end of treatment).
LEO 152020 tablet - Dose regimen 2	LEO 152020 tablet	Participants will be asked to take tablets from Week 0 to Week 16 (end of treatment).
LEO 152020 tablet - Dose regimen 2	LEO 152020 placebo tablet	Participants will be asked to take tablets from Week 0 to Week 16 (end of treatment).
LEO 152020 tablet - Dose regimen 3	LEO 152020 placebo tablet	Participants will be asked to take tablets from Week 0 to Week 16 (end of treatment).
LEO 152020 tablet - Dose regimen 3	LEO 152020 tablet	Participants will be asked to take tablets from Week 0 to Week 16 (end of treatment).
LEO 152020 placebo tablet	LEO 152020 placebo tablet	Participants will be asked to take tablets from Week 0 to Week 16 (end of treatment).

Primary Outcome Measures

Name	Time	Method
Change in EASI From Baseline to Week 16	Week 0 to Week 16	The Eczema Area and Severity Index (EASI) is a validated measure used in clinical trials to evaluate the extent and severity of atopic dermatitis. EASI is a composite score ranging from 0 to 72 with higher scores indicating a more extensive or severe condition.

Secondary Outcome Measures

Name	Time	Method
Number of Adverse Events From Baseline to Week 16+3 Days Per Subject	Week 0 to Week 16+3 days	Only treatment-emergent adverse events will be reported for this outcome measure. An adverse event will be considered treatment emergent if occurring after the first dose of treatment (Week 0) and up until 3 days after the last dose of treatment (Week 16+3 days for a participant completing the 16-week treatment period).