A Study to Assess the Long-term Safety and Efficacy of a Subcutaneous Formulation of Efgartigimod in Adults With Active Idiopathic Inflammatory Myopathy

NCT05979441 | Enrolling By Invitation Phase 3 FDA Drug

• 2 other identifiers: ARGX-113-20112022-502851-79-00
• Study Type: interventional
• Target: 240
• Locations: 28 countries
• Sites: 84

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.

Conditions

Myositis; Dermatomyositis; Active Idiopathic Inflammatory Myopathy; Polymyositis; Immune-Mediated Necrotizing Myopathy; Antisynthetase Syndrome

Outcome Measures

Primary Outcomes (1)

• Incidence of AEs, SAEs and AESIs over time

  AE : adverse event ; SAE : serious adverse event ; AESI : adverse event of special interest.

  Up to 53 months

Secondary Outcomes (21)

• C-GTI comprising the AIS over time

  Up to 51 months

• C-GTI comprising the CWS over time

  Up to 51 months

• C-GTI comprising the GTI-MD over time

  Up to 51 months

• Prednisone dose reduction (average monthly dose) over time

  Up to 51 months

• TIS over time

  Up to 51 months

Study Arms (1)

Efgartigimod PH20 SC

EXPERIMENTAL

Participants receiving efgartigimod PH20 subcutaneously

Biological: Efgartigimod PH20 SC

Interventions

Efgartigimod PH20 SC BIOLOGICAL

Subcutaneous injection of Efgartigimod PH20 given by vials or prefilled syringe (PFS)

Efgartigimod PH20 SC

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• 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

You may not qualify if:

• 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

Sponsors & Collaborators

• argenx: lead

Study Sites (86)

Neuromuscular Clinical and Research Center - Neurology

Phoenix, Arizona, 85028, United States

Location

Attune Health Research, Inc

Beverly Hills, California, 90039, United States

Location

UCI Health - ALS and Neuromuscular Center - Neurology

Orange, California, 92868, United States

Location

UCSF Health - ALS and Neurodegenerative Disease Center - Dermatology

San Francisco, California, 94143, United States

Location

Yale Cancer Center-Yale University School Of Medicine

New Haven, Connecticut, 06520, United States

Location

UF Health - Rheumatology Medical Specialties Medical Plaza

Gainesville, Florida, 32610, United States

Location

Mayo Clinic - Florida - Neurology

Jacksonville, Florida, 32224, United States

Location

University of South Florida (USF) - Morsani Center (USF Health Carol and Frank Morsani Center for Advanced Healthcare)

Tampa, Florida, 33616, United States

Location

Emory Healthcare - Emory Clinic - Rheumatology

Atlanta, Georgia, 30322, United States

Location

Northwestern Medicine - Northwestern Memorial Hospital

Chicago, Illinois, 60611, United States

Location

Northwell Health Physician Partners Rheumatology

Great Neck, New York, 11021, United States

Location

University of North Carolina (UNC) School of Medicine

Chapel Hill, North Carolina, 27514, United States

Location

The Ohio State University

Columbus, Ohio, 43201, United States

Location

Oregon Health and Science University

Portland, Oregon, 97239, United States

Location

University of Pittsburgh Medical Center

Pittsburgh, Pennsylvania, 15261, United States

Location

Austin Neuromuscular Center (National Neuromuscular Research Institute, PLLC)

Austin, Texas, 78759, United States

Location

Nerve And Muscle Center Of Texas

Houston, Texas, 77030, United States

Location

Framingham Centro Medico

La Plata, B1902COS, Argentina

Location

Centro Dermatologico Schejtman

San Miguel, B1663GKT, Argentina

Location

Centro Medico Privado de Reumatologia

San Miguel de Tucumán, 4000, Argentina

Location

Tirol Kliniken - A.o. Landeskrankenhaus Innsbruck - Neurology

Innsbruck, 6020, Austria

Location

AZ Sint-Lucas - Campus Sint-Lucas - Neurology

Ghent, 9000, Belgium

Location

Universitair Ziekenhuis Leuven Gasthuisberg Campus

Leuven, 3000, Belgium

Location

Medical Centre Artmed

Plovdiv, 4002, Bulgaria

Location

Multiprofile hospital for active treatment Kaspela EOOD

Plovdiv, 4002, Bulgaria

Location

Peking University Third Hospital

Beijing, 100191, China

Location

Peking Union Medical College Hospital

Beijing, 100730, China

Location

Sichuan Provincial Academy of Medical Sciences and Sichuan Provincial People's Hospital

Chengdu, 610072, China

Location

Shanghai Jiao Tong University School of Medicine - Renji Hospital - Shanghai Institute of Digestive Disease (SIDD)

Shanghai, 200001, China

Location

Huashan Hospital Affiliated to Fudan University

Shanghai, 200040, China

Location

China Medical University (CMU) - First Affiliated Hospital

Shenyang, 110001, China

Location

First Affiliated Hospital (Henan Medical University - First Affiliated Hospital)-Zhengzhou University

Zhengzhou, 450052, China

Location

Cyprus Institute of Neurology and Genetics

Nicosia, 2371, Cyprus

Location

Revmatologicky Ustav

Prague, 12850, Czechia

Location

Copenhagen University Hospital-Rigshospitalet University Hospital

Copenhagen, 2100, Denmark

Location

Reference Center Neuro-Muscular Diseases - CHU Paris Group Hospitalier La Pitie Salpetriere-Charles Foix

Paris, 75013, France

Location

Aversi Clinic

Tbilisi, 0160, Georgia

Location

LLC MediClub Georgia

Tbilisi, 0160, Georgia

Location

New Hospitals

Tbilisi, 0162, Georgia

Location

The First Medical Center

Tbilisi, 0180, Georgia

Location

Charite Universitaetsmedizin Berlin - Campus Charite Mitte (CCM) - Rheumatology

Berlin, 10117, Germany

Location

Universitaetsklinikum Hamburg-Eppendorf

Hamburg, 20246, Germany

Location

Rheumazentrum Ruhrgebiet

Herne, 44649, Germany

Location

Universitatsmedizin Mannheim GmbH

Mannheim, 68167, Germany

Location

Universitaetsklinikum Tuebingen (UKT)

Tübingen, 72076, Germany

Location

Klinikum der Universitaet Ulm

Ulm, 89081, Germany

Location

National and Kapodistrian University of Athens - School of Health Sciences - Faculty of Medicine

Athens, 115 27, Greece

Location

National and Kapodistrian University of Athens - Eginition Hospital

Athens, 115 28, Greece

Location

ATTIKON University General Hospital - Neurology

Athens, 12462, Greece

Location

University College Dublin (UCD) - St. Vincent's University Hospital (SVUH)

Dublin, D04 T6F4, Ireland

Location

Azienda Ospedaliero Universitaria Consorziale Policlinico

Bari, 70124, Italy

Location

Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) - Ospedale San Raffaele Hospital

Milan, 20132, Italy

Location

Azienda Ospedaliero Universitaria Pisana - Ospedale Santa Chiara - Rheumatology

Pisa, 56126, Italy

Location

Ospedale Sant'Andrea Hospital

Roma, 00189, Italy

Location

Fondazione Policlinico Universitario Agostino Gemelli - Neurology

Roma, 168, Italy

Location

Azienda sanitaria universitaria Friuli Centrale - ASUFC

Udine, 33100, Italy

Location

Juntendo University Hospital

Bunkyō City, 113-8431, Japan

Location

The University of Tokyo Hospital

Bunkyō City, 113-8655, Japan

Location

Japan Community Healthcare Organization Chukyo Hospital

Nagoya, 457-8510, Japan

Location

Institute of Science Tokyo Hospital

Tokyo, 113-8519, Japan

Location

Wakayama Medical University Hospital

Wakayama, 641-8510, Japan

Location

Santaros University Clinic

Vilnius, 08410, Lithuania

Location

Hospital Angeles Clinica Londres

Mexico City, 06700, Mexico

Location

Amsterdam UMC Research BV

Amsterdam, 1105 AZ, Netherlands

Location

Clinica San Juan de Dios - sede Arequipa - Rheumatology

Arequipa, 4000, Peru

Location

Instituto Peruano Del Hueso Y La Articulacion Sac-Privado-Lima,Centro De Investigacion Iphar

Lima, 27, Peru

Location

Investigaciones Clinicas S.A.C.

Lima, 33, Peru

Location

USK-WAM Centralny Szpital Weteranow - Szpital Kniniczny ul. Zeromskiego 113 - Rheumatology

Lodz, 90-549, Poland

Location

Centrum Wsparcia Badan Klinicznych Pomorskiego Uniwersytetu Medycznego w Szczecinie (CWBK PUM) - Rheumatology

Szczecin, 71-252, Poland

Location

Centro Hospitalar do Porto - Hospital Santo Antonio

Porto, 4099-001, Portugal

Location

Clinical Center of Serbia

Belgrade, 11000, Serbia

Location

Institute of Rheumatology

Belgrade, 11000, Serbia

Location

Seoul National University Hospital

Seoul, 03080, South Korea

Location

Hospital de la Santa Creu i Sant Pau

Barcelona, 08041, Spain

Location

Hospital Universitario 12 de Octubre

Madrid, 28041, Spain

Location

Hospital Universitari i Politecnic La Fe de Valencia - Neurology

Valencia, 46026, Spain

Location

Karolinska Universitestssjukhus Solna

Solna, 17176, Sweden

Location

Chung Shan Medical University Hospital

Taichung, 402, Taiwan

Location

King Chulalongkorn Memorial Hospital - Neurology

Bangkok, 10330, Thailand

Location

Phramongkutklao Hospital

Bangkok, 10400, Thailand

Location

Ramathibodi hospital

Bangkok, 10400, Thailand

Location

Siriraj Hospital, Mahidol University of Internal medicine

Bangkok, 10700, Thailand

Location

Faculty Of Medicine, Khon Kaen University

Khon Kaen, 40002, Thailand

Location

Aintree University Hospital - Liverpool University Hospitals NHS Foundation Trust

Liverpool, L9 7AL, United Kingdom

Location

The Royal Free Hospital

London, NW3 2QG, United Kingdom

Location

Northern Care Allicance NHS Foundation Trust - Salford Royal - Rheumatology

Salford, M6 8HD, United Kingdom

Location

Related Links

• Study website

MeSH Terms

Conditions

Myositis; Dermatomyositis; Polymyositis; Antisynthetase syndrome

Condition Hierarchy (Ancestors)

Muscular Diseases; Musculoskeletal Diseases; Neuromuscular Diseases; Nervous System Diseases; Connective Tissue Diseases; Skin and Connective Tissue Diseases; Skin Diseases

Study Design

• Study Type: interventional
• Phase: phase 3
• Allocation: NA
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: SINGLE GROUP
• Sponsor Type: INDUSTRY
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: July 28, 2023
• First Posted: August 7, 2023
• Study Start: September 12, 2023
• Primary Completion (Estimated): September 1, 2028
• Study Completion (Estimated): September 1, 2028
• Last Updated: April 23, 2026

Record last verified: 2026-04

Locations

AR (3); JP (5); BE (2); TW (1); GR (3); ES (3); PE (3); SE (1); PL (2); TH (5); DK (1); US (17); LI (1); KR (1); PT (1); CN (7); NL (1); ME (1); CZ (1); GB (3); DE (6); GE (4); IE (1); FR (1); AU (1); BU (2); IT (6); CY (1)