Active Idiopathic Inflammatory Myopathy, Antisynthetase Syndrome, Dermatomyositis, Immune-Mediated Necrotizing Myopathy, Myositis, Polymyositis
Conditions
Brief summary
The main purpose of this study is to measure the long-term safety and tolerability of efgartigimod PH20 SC in adult participants with Idiopathic Inflammatory Myopathy (IIM) who previously participated in ARGX-113-2007. The study consists of a treatment period where participants will receive efgartigimod PH20 SC for up to 51 months. The treatment period will be followed by a treatment-free safety follow-up period of 56 days.
Interventions
BIOLOGICALEfgartigimod PH20 SC
Subcutaneous injection of Efgartigimod PH20 given by vials or prefilled syringe (PFS)
Sponsors
argenx
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
TREATMENT
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Has completed trial ARGX-113-2007 * Being capable of providing signed informed consent and complying with protocol requirements * Agrees to use contraceptive measures consistent with local regulations and women of childbearing potential must have a negative urine pregnancy test at baseline before receiving the study drug
Exclusion criteria
* Intention to have major surgery during the study period or any other medical condition that has arisen since enrollment in study ARGX-113-2007, that in the investigator's opinion, would confound the results of the study or put the participant at undue risk * Known hypersensitivity reaction to the study drug or 1 of its excipients * Development of any malignancy, either new or recurrent, other than basal cell carcinoma of the skin, regardless of relatedness
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Incidence of AEs, SAEs and AESIs over time | Up to 53 months | AE : adverse event ; SAE : serious adverse event ; AESI : adverse event of special interest. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| C-GTI comprising the AIS over time | Up to 51 months | The Composite Glucocorticoid Toxicity Index (C-GTI) serves as a primary instrument to capture toxicities likely caused by glucocorticoid exposure and enables monitoring of long-term tolerability of glucocorticoids during prolonged use. The Aggregate Improvement Score (AIS) is an analytical scores generated from the weighted C-GTI. The AIS can be used to assess whether a new therapy is effective in reducing glucocorticoid toxicity over time; higher AIS scores are associated with less toxicity. |
| C-GTI comprising the CWS over time | Up to 51 months | The Composite Glucocorticoid Toxicity Index (C-GTI) serves as a primary instrument to capture toxicities likely caused by glucocorticoid exposure and enables monitoring of long-term tolerability of glucocorticoids during prolonged use. The Cumulative Worsening Score (CWS) is an analytical score generated from the weighted C-GTI. The CWS is designed to assess cumulative glucocorticoid toxicity; higher scores indicate increased steroid toxicity. |
| C-GTI comprising the GTI-MD over time | Up to 51 months | The Composite Glucocorticoid Toxicity Index (C-GTI) serves as a primary instrument to capture toxicities likely caused by glucocorticoid exposure and enables monitoring of long-term tolerability of glucocorticoids during prolonged use. The Glucocorticoid Toxicity Index-Metabolic Domains (GTI-MD) is an abbreviated GTI version limited to the 4 metabolic domains. A GTI-MD score of 0 indicates a low likelihood of toxicity in the assessed metabolic domains. |
| Prednisone dose reduction (average monthly dose) over time | Up to 51 months | — |
| TIS over time | Up to 51 months | The total improvement score (TIS) assesses minimal, moderate, and major clinical response, and it is assessed using the ACR/EULAR criteria. The total score varies between 0 and 100, with higher scores indicating greater improvement. |
| Proportion of TIS responders (minimal, moderate, major) over time | Up to 51 months | The total improvement score (TIS) assesses minimal, moderate, and major clinical response, and it is assessed using the ACR/EULAR criteria. The total score varies between 0 and 100, with higher scores indicating greater improvement |
| Individual CSMs of the TIS over time | Up to 51 months | The total improvement score (TIS) assesses minimal, moderate, and major clinical response, and it is assessed using the ACR/EULAR criteria. The ACR/EULAR criteria calculate TIS using the 6 core set measure (CSMs): MDGA, PGA, MMT8, HAQ-DI, muscle enzymes, and extramuscular global assessment (assessed by the MDAAT). |
| Percentage of participants with clinically inactive disease | Up to 51 months | Clinically inactive disease is defined as no evidence of disease activity, based on an Physician Global Assessment of Disease Activity (MDGA) and Extramuscular Global Assessment of the Myositis Disease Activity Assessment Tool (MDAAT) of 0 and normal creatine kinase (CK) values for at least 12 weeks (at week 28 and every 24 weeks thereafter). |
| Percentage of participants with remission during the study | Up to 51 months | Remission is defined as a clinically inactive disease for at least 24 weeks |
| PGI-S over time | Up to 51 months | The Patient Global Impression of Severity (PGI-S) asks participants to rate the severity of their disease symptoms over the past 7 days on a 4-point Likert scale, where scores range from "no symptoms" to "severe." |
| CGI-S over time | Up to 51 months | The Clinical Global Impression of Severity (CGI-S) asks the physician to rate the severity of the participant's disease on a 4-point Likert scale, where scores range from "no activity" to "severe". |
| Physical Functioning subscale and Physical Component Summary scores of the SF-36v2 over time | Up to 51 months | The 36-Item Short Form Survey version 2 (SF-36v2) is a 36-item scale constructed to survey health-related quality of life in 8 domains. |
| EQ-5D-5L utilities over time | Up to 51 months | The EQ-5D-5L questionnaire is a standardized test recognized by many health authorities as a generic measure of health status for clinical and economic appraisal. The descriptive system comprises 5 dimensions, each having 5 levels ranging from "No problem" to "Extreme problem". |
| EQ-5D-5L VAS over time | Up to 51 months | The EQ-5D-5L questionnaire is a standardized test recognized by many health authorities as a generic measure of health status for clinical and economic appraisal. A visual analog scale (VAS) is included in the EQ-5D-5L, where participants will mark their health status from 0 (the worst health you can imagine) to 100 (the best health you can imagine). |
| Percent change from baseline in total IgG levels in serum over time | Up to 53 months | — |
| Incidence of ADA against efgartigimod (serum levels) over time | Up to 53 months | ADA : anti-drug antibodies. |
| Proportion of participants achieving sustained low disease activity while on IMP, over time | Up to 51 months | Sustained low disease activity is defined as a CGI-S score of "mild" or "no activity" and a PGI-S score of "mild" or "no symptoms" for at least 12 weeks. |
| Proportion of participants with low disease activity over time, while on IMP | Up to 51 months | Low disease activity is defined as a CGI-S score of "mild" or "no activity" and a PGI-S score of "mild" or "no symptoms" |
| Proportion of participants with low disease activity who continue dosing every 2 weeks at week 52 and every 24 weeks thereafter | Up to 51 months | Low disease activity is defined as a CGI-S score of "mild" or "no activity" and a PGI-S score of "mild" or "no symptoms" |
| Proportion of participants who have marked worsening during the period of dosing every 2 weeks | Up to 51 months | Marked worsening is defined as a CGI-S score of "moderate" or "severe" and a PGI-S score of "moderate" or "severe" |
| Duration of dosing every 2 weeks | Up to 51 months | — |
Countries
Argentina, Austria, Belgium, Bulgaria, China, Cyprus, Czechia, Denmark, France, Georgia, Germany, Greece, Ireland, Italy, Japan, Lithuania, Mexico, Netherlands, Peru, Poland, Portugal, Serbia, South Korea, Spain, Sweden, Taiwan, Thailand, United Kingdom, United States
Outcome results
None listed