Active Idiopathic Inflammatory Myopathy, Myositis, Dermatomyositis, Polymyositis, Immune-Mediated Necrotizing Myopathy, Antisynthetase Syndrome
Conditions
Brief summary
This study's purpose is to measure the treatment response from efgartigimod PH20 SC compared with placebo in participants with Idiopathic Inflammatory Myopathy (IIM). Participants with the IIM subtypes of dermatomyositis (DM), immune-mediated necrotizing myopathy (IMNM), or certain other subtypes of polymyositis (PM; including antisynthetase syndrome \[ASyS\]) will be included in the study. Treatment response will be measured by Total improvement score (TIS).
Interventions
BIOLOGICALEFG PH20 SC
Subcutaneous injection of efgartigimod coformulated with rHuPH20, a permeation enhancer
OTHERPBO
Subcutaneous injection of placebo coformulated with rHuPH20, a permeation enhancer
Sponsors
argenx
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
DOUBLE (Subject, Investigator)
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Ability to consent in the jurisdiction in which the study is taking place and capable of giving signed informed consent. * A definite or probable clinical diagnosis of idiopathic inflammatory myopathy (IIM) * One of the following medical histories: Diagnosis of dermatomyositis (DM) or juvenile dermatomyositis (JDM), Diagnosis of polymyositis (PM) (including antisynthetase syndrome (ASyS)), Diagnosis of immune-mediated necrotizing myopathy (IMNM) * Diagnosed with active disease as defined by the presence of at least 1 of the following criteria: Abnormal levels of at least 1 of the following enzymes: creatine kinase (CK), aldolase, lactate dehydrogenase, aspartate aminotransaminase (AST), alanine aminotransferase (ALT), based on central laboratory results; Electromyography demonstrating active disease within the past 3 months; Active dermatomyositis (DM) skin rash; Muscle biopsy indicative of active idiopathic inflammatory myopathy (IIM) in the past 3 months; Magnetic resonance imaging within the past 3 months indicative of active inflammation * Muscle weakness * Receiving a permitted background treatment for idiopathic inflammatory myopathy. * Contraceptive use consistent with local regulations, where available, for individuals participating in clinical studies. Women of childbearing potential must have a negative serum pregnancy test during screening and a negative urine pregnancy test at baseline before receiving investigational medicinal product (IMP).
Exclusion criteria
* Any other known autoimmune disease that, in the investigator's opinion, would interfere with an accurate assessment of clinical symptoms of idiopathic inflammatory myopathy (IIM) or put the patient at undue risk * A history of malignancy unless considered cured by adequate treatment, with no evidence of recurrence for ≥ 3 years before the first administration of the investigational medicinal product (IMP). Adequately treated participants with the following cancers can be included at any time: Basal cell or squamous cell skin cancer ; Carcinoma in situ of the cervix; Carcinoma in situ of the breast; Incidental histological finding of prostate cancer * Severe muscle damage * Glucocorticoid-induced myopathy that the investigator considers the primary cause of muscle weakness or permanent weakness linked to a non-idiopathic inflammatory myopathy (IIM) cause * Uncontrolled interstitial lung disease or any other uncontrolled idiopathic inflammatory myopathy (IIM) manifestation that, in the opinion of the investigator, would be likely to require treatment with prohibited medication during the study * Participant is pregnant or lactating or intends to become pregnant during the study.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Mean TIS | phase 2: 24 weeks; phase 3: 52 weeks | The Total improvement score (TIS) assesses minimal, moderate, and major clinical response, and is assessed using the ACR/EULAR criteria. It is measured on a 0 to 100 scale. Higher scores represent improvement; zero indicates no improvement or worsening (from baseline). |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Time to reach TIS ≥ 20 (first "minimal clinical improvement") | phase 2: up to 24 weeks; phase 3: up to 52 weeks | The Total improvement score (TIS) assesses minimal, moderate, and major clinical response, and is assessed using the ACR/EULAR criteria. It is measured on a 0 to 100 scale. Higher scores represent improvement; zero indicates no improvement or worsening (from baseline). |
| Percentage of participants with TIS ≥ 20 | phase 2: up to 24 weeks; phase 3: up to 52 weeks | The Total improvement score (TIS) assesses minimal, moderate, and major clinical response, and is assessed using the ACR/EULAR criteria. It is measured on a 0 to 100 scale. Higher scores represent improvement; zero indicates no improvement or worsening (from baseline). |
| Time to reach TIS ≥ 40 (first "moderate clinical improvement") | phase 2: up to 24 weeks; phase 3: up to 52 weeks | The Total improvement score (TIS) assesses minimal, moderate, and major clinical response, and is assessed using the ACR/EULAR criteria. It is measured on a 0 to 100 scale. Higher scores represent improvement; zero indicates no improvement or worsening (from baseline). |
| Percentage of participants with TIS ≥ 40 | phase 2: up to 24 weeks; phase 3: up to 52 weeks | The Total improvement score (TIS) assesses minimal, moderate, and major clinical response, and is assessed using the ACR/EULAR criteria. It is measured on a 0 to 100 scale. Higher scores represent improvement; zero indicates no improvement or worsening (from baseline). |
| Change in MMT8 score | phase 2: up to 24 weeks; phase 3: up to 52 weeks | The manual muscle testing-8 (MMT8) is a physician assessment of muscle strength in a set of 8 designated muscles tested bilaterally and axially. The highest total potential MMT8 score is 150 |
| Change in Patient Global Assessment of Disease Activity (PGA) | phase 2: up to 24 weeks; phase 3: up to 52 weeks | The Patient Global Assessment of Disease Activity (PGA) is a tool that measures a patient's global evaluation of their overall disease activity at the time of assessment using a 10-cm VAS. The participant rates their overall disease activity by drawing a vertical mark on a 10-cm VAS from the left end of the line (no evidence of disease activity) to the right end of the line (extremely active or severe disease activity). |
| Change in Physician Global Assessment of Disease Activity (MDGA) | phase 2: up to 24 weeks; phase 3: up to 52 weeks | The Physician Global Assessment of Disease Activity (MDGA) is a tool that measures the physician's global evaluation of the participant's overall disease activity, defined as potentially reversible pathology or physiology resulting from IIM. The physician rates disease activity on the MDGA using a 10-cm VAS. Overall disease activity is rated by drawing a vertical mark on a 10-cm VAS from the left end of the line (no evidence of disease activity), midpoint of the line (moderate disease activity), and the right end of the line (extremely active or severe disease activity). |
| Proportion of participants who have at least moderate improvement (≥40) in TIS at week 52 and adhere to an oral prednisone dosage of ≤5 mg/day (or equivalent) from week 44 onward | Phase 3: up to 52 weeks | The Total improvement score (TIS) assesses minimal, moderate, and major clinical response, and is assessed using the ACR/EULAR criteria. It is measured on a 0 to 100 scale. Higher scores represent improvement; zero indicates no improvement or worsening (from baseline). |
| Change in CK abnormality grades at week 52 | Phase 3: up to 52 weeks | CK: creatine kinase |
| Change in CDASI activity score at week 52 | Phase 3: up to 52 weeks | The Cutaneous Dermatomyositis Disease Area and Severity Index (CDASI) is a skin-specific outcome measure used to assess disease in patients with Dermatomyositis (DM). Disease in 15 different anatomical locations is rated using 3 activity measures (erythema, scale, erosion/ulceration) and 2 damage measures (poikiloderma, calcinosis). The resulting activity and damage scores range from 0 to 100 and 0 to 32, respectively. Higher scores indicate greater disease severity. |
Countries
Argentina, Australia, Austria, Belgium, Bulgaria, Canada, China, Cyprus, Czechia, Denmark, France, Georgia, Germany, Greece, Hungary, Ireland, Israel, Italy, Japan, Lithuania, Mexico, Netherlands, Peru, Poland, Portugal, Serbia, Slovakia, South Korea, Spain, Sweden, Switzerland, Taiwan, Thailand, Turkey (Türkiye), United Kingdom, United States
Outcome results
None listed