A Study to Evaluate the Efficacy and Safety of ESK-001 in Patients With Plaque Psoriasis

Study Overview
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Brief Summary
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This is a multi-center, randomized, double-blind, placebo-controlled study in patients with moderate to severe plaque psoriasis.

Detailed Description
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This study will consist of a 4 week screening period, 12 week treatment period, and a 4 week follow up period for a total of 20 weeks. Each participant will be randomized to receive ESK-001 or placebo daily for 12 weeks. An open label extension study will be available for those patients who complete the study.

Official Title
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A Randomized, Double-Blind, Placebo-Controlled Study to Evaluate the Efficacy and Safety of ESK-001 in Patients With Moderate to Severe Plaque Psoriasis

Conditions
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Plaque Psoriasis

Intervention / Treatment
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* Drug: ESK-001
* Drug: Placebo


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Total body weight >40 kg (88 lb) Men and woman age 18-75 Men and Women must use highly effective methods of contraception for the entirety of the study Exclusion Criteria: History of malignancy within the last 5 years Positive for HIV, Hepatitis B or C History of tuberculosis Diagnosis of non-plaque psoriasis Patients with QTcF >450 msec (males) or >470 msec (females) at screening Live vaccines

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 75 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: ESK-001 Dose Level 1<br>ESK-001 administered as an oral tablet | Drug: ESK-001<br>* Oral tablet<br>|
| Experimental: ESK-001 Dose Level 2<br>ESK-001 administered as an oral tablet | Drug: ESK-001<br>* Oral tablet<br>|
| Experimental: ESK-001 Dose Level 3<br>ESK-001 administered as an oral tablet | Drug: ESK-001<br>* Oral tablet<br>|
| Experimental: ESK-001 Dose Level 4<br>ESK-001 administered as an oral tablet | Drug: ESK-001<br>* Oral tablet<br>|
| Experimental: ESK-001 Dose Level 5<br>ESK-001 administered as an oral tablet | Drug: ESK-001<br>* Oral tablet<br>|
| Placebo Comparator: Placebo<br>Placebo administered as an oral tablet | Drug: Placebo<br>* Oral tablet<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| To compare the Psoriasis Area and Severity Index (PASI-75) between doses of ESK-001 and placebo | Proportion of patients with moderate to severe psoriasis achieving ≥75% reduction in PASI score | 12 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| To assess the safety and tolerability of ESK-001 dose in moderate to severe psoriasis patients | Incidence of treatment-emergent adverse events (TEAEs) and serious adverse events (SAEs) | 12 weeks | 
| To assess the response rate in static Physician's Global Assessment (sPGA) score | Proportion of patients achieving an sPGA score of 0 (cleared) or 1 (minimal) | 12 weeks | 
| To characterize the pharmacokinetics (PK) of ESK-001 (Cmax) | Plasma concentrations and PK parameters including steady-state maximum observed concentration (Cmax) for ESK-001 at Week 8 | 8 weeks | 
| To characterize the pharmacokinetics (PK) of ESK-001 (Ctrough) | Plasma concentrations and PK parameters including steady-state trough observed plasma concentration (Ctrough) for ESK-001 at Week 8 | 8 weeks |