A Phase 3 Study to Evaluate the Efficacy and Safety of Efgartigimod IV in Patients With Acetylcholine Receptor Binding Antibody Seronegative Generalized Myasthenia Gravis

Running, not enrolling · Phase 3 · Has a placebo group

Conditions studied: Generalized Myasthenia Gravis, gMG, Myasthenia Gravis, Generalized, Myasthenia Gravis

In brief

The primary purpose of this study is to measure the efficacy and safety of efgartigimod IV compared to placebo in participants with Acetylcholine Receptor Binding Antibody (AChR-Ab) seronegative Generalized Myasthenia Gravis (gMG). The study consists of a Part A where participants will be randomized to receive either efgartigimod IV or placebo IV and a Part B where participants completing part A will receive open-label efgartigimod IV. Participants will be in the study for up to (approximately) 2.5 years.

Key facts

Study ID

NCT06298552

Run by

argenx

People needed

119

Starts

2024-04-16

Expected to finish

2027-06-01

Last updated by the study team

2025-11-05

Who can join

Age: 18 and older. Sex: any. Healthy volunteers: not accepted.

You may qualify if…

• The participant is at least 18 years of age and the local legal age of consent for clinical studies when signing the ICF.
• The participant is capable of providing signed informed consent and following with protocol requirements.
• The participant agrees to use contraceptive measures consistent with local regulations and the women of child-bearing potential (WOCBP) must have a negative serum pregnancy test result at screening and a negative urine pregnancy test result at baseline before receiving the study drug.
• The participant has no known weakness in infancy and later develop fatigable weakness after aged 16 years and diagnosed with acquired gMG of both of the following:
• History of abnormal neuromuscular transmission demonstrated by single fiber electromyography or repetitive nerve stimulation (RNS) or is anti-muscle-specific kinase antibodies (MuSK-Ab) seropositive
• Either a history of positive edrophonium chloride test OR a demonstrated improvement in MG signs with treatments such as oral acetylcholinesterase (AChE) inhibitors, plasma exchange (PLEX), immunoabsorption, or intravenous immunoglobulin (IVIg)/ subcutaneous immunoglobulin (SCIg) treatment
• The participant is receiving a stable dose of MG therapy before screening that includes acetylcholinesterase (AChE) inhibitors, steroids, or nonsteroidal immunosuppressive therapies (NSISTs) in combination or alone.

You may not qualify if…

• Known autoimmune disease or any medical condition that would interfere with an accurate assessment of clinical symptoms of gMG or puts the participant at undue risk
• History of malignancy, cancer, unless considered cured by adequate treatment with no evidence of recurrence for ≥3 years. 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 findings of prostate cancer
• Clinically significant active infection that is not sufficiently resolved in the investigator's opinion or positive serum test at screening for active infection with any of the following: Hepatitis B virus (HBV), Hepatitis C virus (HCV), HIV
• History of or current alcohol, drug, or medication abuse as assessed by the investigator
• Pregnant or lactating state or intention to become pregnant during the study
• Live or live-attenuated vaccine received \<4 weeks before screening
• Worsening muscle weakness secondary to concurrent infections or medications
• Received a thymectomy less than 3 months before screening or thymectomy is planned during the study
• The complete list of exclusion criteria can be found in the protocol.

Where it is running

• Loma Linda University Health — Fresno, California, United States
• First Choice Neurology Boca Raton — Boca Raton, Florida, United States
• SFM Clinical Research LLC — Boca Raton, Florida, United States
• The Neurology Institute / Healthcare Innovations Institute - Coral Springs — Coral Springs, Florida, United States
• Neurology Associates PA — Maitland, Florida, United States
• Desai Sethi Medical Center — Miami, Florida, United States
• Medsol Clinical Research Center Inc — Port Charlotte, Florida, United States
• BayCare - St. Anthony's Hospital — St. Petersburg, Florida, United States
• University of South Florida (USF) Health - Morsani Center for Advanced Healthcare — Tampa, Florida, United States
• Wellstar - Augusta University Medical Center — Augusta, Georgia, United States
• Kansas University Medical Center - Kansas City — Fairway, Kansas, United States
• Rutgers-Robert Wood Johnson Medical School — New Brunswick, New Jersey, United States
• University of North Carolina - Chapel Hill — Chapel Hill, North Carolina, United States
• Duke University School of Medicine - Duke Early Phase Clinical Research Unit — Durham, North Carolina, United States
• Cleveland Clinic — Cleveland, Ohio, United States
• Erlanger Neuroscience Institute — Chattanooga, Tennessee, United States
• National Neuromuscular Research Institute — Austin, Texas, United States
• University of Washington Medical Center - Montlake — Seattle, Washington, United States
• Hôpital Erasme — Anderlecht, Belgium
• Cliniques Universitaires Saint-Luc — Brussels, Belgium
• AZ Sint-Lucas Gent — Ghent, Belgium
• UZ Leuven — Leuven, Belgium
• Heritage Medical Research Clinic — Calgary, Canada
• Genge Partners Inc. — Montreal, Canada
• HonorHealth Neurology - Bob Bove Neuroscience Institute — Scottsdale, Arizona, United States

Full record on ClinicalTrials.gov

Trial information comes from ClinicalTrials.gov and is refreshed daily. TrialsForMe does not provide medical care and does not run the studies it lists.