An Extension Study for Participants Who Have Completed the Treatment Period of a Qualifying Parent Study

Study Overview
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Brief Summary
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The purpose of this research study is to evaluate the long-term safety, and tolerability of PF-06823859 study drug in adult participants with Dermatomyositis (DM) from a qualifying study.

Official Title
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AN OPEN LABEL, LONG-TERM EXTENSION STUDY TO INVESTIGATE THE SAFETY OF PF-06823859 ADMINISTERED TO ADULT PARTICIPANTS ≥18 AND ≤80 WITH ACTIVE DERMATOMYOSITIS.

Conditions
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Dermatomyositis

Intervention / Treatment
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* Drug: Anti-Beta Interferon (PF-06823859)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Participants aged ≥18 and ≤80 with moderate to severe dermatomyositis (DM), that have completed the treatment period of a qualifying study. Capable of giving signed informed consent. Participants who are willing and able to comply with all scheduled visits, treatment plan, laboratory tests, lifestyle considerations, and other study procedures. Exclusion Criteria: Other medical or psychiatric condition including recent (within the past year) or active suicidal ideation/behavior or laboratory abnormality that may increase the risk of study participation or, in the investigator's judgment, make the participant inappropriate for the study Participants who met discontinuation criteria at any point during the participating qualifying studies. Participants with an ongoing safety event in the qualifying studies which, in the opinion of the investigator or sponsor, is an ongoing safety concern OR the participant has met safety monitoring criteria in the qualifying study that has not resolved.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 80 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
Intervention Model: Single Group Assignment
Interventional Model Description: Eligible participants will have completed the treatment period of a qualifying Dermatomyositis parent study. All participants will receive active study drug.
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Anti-Beta Interferon drug (PF-06823859)<br>IV infusion | Drug: Anti-Beta Interferon (PF-06823859)<br>* IV infusion<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Incidence of Treatment Emergent Adverse Events (AEs) |  | Week 52 | 
| Incidence of Clinically Significant Treatment Emergent Laboratory Abnormalities |  | Week 52 | 
| Incidence of Clinically Significant Changes In Vital Signs |  | Week 52 | 
| Incidence of Clinically Significant New Electrocardiogram (ECG) Findings |  | Week 52 | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change from Baseline in Cutaneous Dermatomyositis Disease Area and Severity Index (CDASI) Activity Score at Week 52 | The Cutaneous Dermatomyositis Disease Area and Severity Index (CDASI), a skin-based outcome measure, was developed to systematically assess the extent of cutaneous disease in patients with DM. The CDASI scale is a validated DM-specific instrument designed to capture the extent of cutaneous disease. Disease involvement in 15 different anatomical locations is rated using three activity (erythema, scale, erosion/ulceration) and two damage (poikiloderma, calcinosis) measures. The presence and severity of Gottron's papules, periungual changes and alopecia are also captured. The resulting activity and damage scores range from 0 to 100 and 0 to 32, respectively. Higher scores indicate greater disease severity. | Week 52 | 
| Absolute Values and Change From Baseline of Cutaneous Dermatomyositis Disease Area and Severity Index (CDASI) Activity Scores |  | Baseline, Weeks 12, 24, 36, 48 and 52 | 
| Absolute Values and Change From Baseline of CDASI Damage Score |  | Baseline, Weeks 12, 24, 36, 48 and 52 | 
| Total Improvement Score (TIS) at Week 52 and at intermediate scheduled timepoints for participants who entered from stage 3 of protocol C0251002 |  | Week 52 | 
| Change Over Time In the Physician Global Assessment (PhGA) | Clinical assessment completed by the physician of the overall disease status | Week 52 | 
| Change over time in the Patient Global Assessment PtGA | Clinical assessment completed by the study participant of their overall disease status | Week 52 | 
| Change over time in the Manual Muscle Testing 8 groups (MMT-8) | Clinical assessment of muscle disease | Week 52 | 
| Change Over Time In the Health Assessment Quality of Life and Disability Index (HAQ-DI) | Patient reported outcome on how the study participant rate their health assessment and quality of life and disability | Week 52 | 
| Change in Muscle Enzyme Laboratory Values Over Time | For muscle enzymes, the most abnormal serum muscle enzyme level at baseline (creatine kinase, aldolase, alanine transaminase, aspartate aminotransferase, lactate dehydrogenase) is used | Week 52 | 
| Change Over Time In the Myositis Disease Activity Assessment Tool | Clinical assessment completed by the physician to measure the myositis activity | Week 52 |