A Phase III Extended Clinical Trial of Jaktinib Hydrochloride Tablets in the Treatment of Moderate and Severe Atopic Dermatitis

Study Overview
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Brief Summary
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To observe the safety and effectiveness of long-term use of jaktinib hydrochloride tablets in the treatment of moderate and severe atopic dermatitis

Detailed Description
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If the enrolled subjects received the treatment of jaktinib hydrochloride tablets in the ZGJAK025 trial, they will continue to use the drug at the original dosage; If the enrolled subjects received placebo treatment in the ZGJAK025 trial, they will receive 100mg BID of jaktinib hydrochloride tablets, 75mg BID of jaktinib hydrochloride tablets or placebo at a ratio of 1:1:1 at random, and continue to take the drug on an empty stomach, with the longest continuous treatment not exceeding 36 weeks.

Official Title
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A Phase III Extended Clinical Trial of Long-term Safety and Efficacy of Jaktinib Hydrochloride Tablets in the Treatment of Moderate and Severe Atopic Dermatitis

Conditions
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Atopic Dermatitis

Intervention / Treatment
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* Drug: Jaktinib Hydrochloride Tablet


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: The investigator thinks that the subject can continue to benefit from participating in the extension trial; Fully understand the extension trial and sign the informed consent form; Complete the ZGJAK025 trial for 16 weeks and have good compliance; It is expected that the time interval between the first administration and the last administration of ZGJAK025 trial for the subject should be ≤ 4 weeks; Exclusion Criteria: Within 4 weeks before enrollment, there were any adverse events ≥ 3 levels related to the test drug that did not return to level 1 or normal; The investigator thinks that the subject is not suitable for the trial.

Ages Eligible for Study
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Minimum Age: 18 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: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Jaktinib 100mg BID<br>Drug: Jaktinib Hydrochloride Tablet 100mg dosage, orally administered, twice a day | Drug: Jaktinib Hydrochloride Tablet<br>* Orally administered, twice a day<br>|
| Experimental: Jaktinib 75mg BID<br>Drug: Jaktinib Hydrochloride Tablet 75mg dosage, orally administered, twice a day | Drug: Jaktinib Hydrochloride Tablet<br>* Orally administered, twice a day<br>|
| Placebo Comparator: Placebo<br>Drug: Placebo Orally administered, twice a day | Drug: Jaktinib Hydrochloride Tablet<br>* Orally administered, twice a day<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Number and percentage of subjects with treatment emergent adverse event (TEAE) | Safety of the drug | 36 weeks after the first dose | 
| Number and percentage of subjects with Serious Adverse Event (SAE) | Safety of the drug | 36 weeks after the first dose | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The diachronic change in the proportion of subjects whose total Eczema area and severity index （EASI） score decreased by ≥ 75% from baseline | The proportion of subjects who reached EASI-75 | 36 weeks after the first dose | 
| The diachronic change of the proportion of subjects whose systemic Investigator's Global Assessment （IGA） score reached 0 or 1 and decreased by ≥ 2 points from baseline | The proportion of subjects who reached IGA 0/1 | 36 weeks after the first dose | 
| The diachronic change in the proportion of subjects whose pruritus Numerical Rating Scale （NRS） score improved by ≥ 4 points from baseline | The proportion of subjects who reached NRS4 | 36 weeks after the first dose |