A Phase 2/3 interventional study of Efgartigimod PH20 SC in Generalized Myasthenia Gravis, sponsored by argenx. Recruiting at 22 sites in 14 countries. Open to participants aged 2 Years to 17 Years. Per ClinicalTrials.gov, last updated 2026-09-28.
Sponsored by argenx · Phase 2/3, Interventional, and Treatment
Among 20 studies testing efgartigimod alfa in Myasthenia Gravis — 11 open to participants now, 14 under way, 7 of them phase 3. efgartigimod alfa · Myasthenia Gravis.
Among the 20 studies testing efgartigimod alfa in Myasthenia Gravis, this one is the 20th largest by planned enrollment, is one of 5 that started in 2024, is one of 2 in phase 2/3, reaches primary completion later than 11 of the 13 other live ones, and was the 10th registered.
330 studies on the registry are indexed under Myasthenia Gravis; 144 are open to participants now.
Browse Myasthenia Gravis studies →11 of the 20 studies testing efgartigimod alfa in Myasthenia Gravis are open now, in 12 countries. Recruiting first, the newest first:
argenx · Sites in United States, Belgium, Germany and 5 more countries
Ages 18+
Centre Hospitalier Universitaire de Nice · Sites in France
Ages 65+
argenx · Sites in United States
Ages 18+
University of Colorado, Denver · Sites in United States
Ages 18+
Clinique Neuro-Outaouais · Sites in Canada
Ages 18–80
By country, each count listing its studies:
efgartigimod alfa: first FDA approval 2021 (VYVGART), first EMA approval 2022. What it is approved for, and how studies give it, is on its page →
Of the 104 Myasthenia Gravis studies recruiting now, 64 (62%) set no upper age limit and 23 (22%) stop at 75 or younger; 16 take children under 18; 13 take healthy volunteers.
This study: 2 Years to 17 Years · all sexes · no healthy volunteers.
The full table on the hub →This tab as a report to print or save as PDF → With an account.
20 studies; the count open now beside each. This study's row is marked.
A study in two phases is counted once above. Listed by phase, each with its combined phases: Phase 2 5 · Phase 3 12 · Phase 4 4
First in 2016; this study’s year is marked. 5 started in 2024.
This study's planned enrollment of 12 is below the median of 44 across 217 interventional studies indexed under Myasthenia Gravis.
Median enrollment 55 across the 20 interventional studies. Of the 6 that completed or were terminated, 6 (100%) have results posted.
This tab as a report to print or save as PDF → With an account.
12 of 20 have an industry lead sponsor. The 8 most frequent:
argenx is the lead sponsor of 87 studies on the registry; 29 are open to participants now.
Of its 22 completed or terminated interventional studies of FDA-regulated products, 16 (73%) have results posted.
18 studies in Myasthenia Gravis by argenx: 9 open now, 12 under way, 5 of them phase 3. Of 6 finished, 6 (100%) have results posted.
Among the 18 studies in Myasthenia Gravis by argenx, this one is the 13th largest by planned enrollment of the 14 interventional ones that give a count, is one of 4 that started in 2024, is one of 3 in phase 2/3, reaches primary completion later than 4 of the 11 other live ones, and was the 12th registered.
argenx’s Myasthenia Gravis studies by the year they started, since 2016.
7 of the studies testing efgartigimod alfa in Myasthenia Gravis that are under way reach primary completion within a year, 4 of them phase 3. Phase 3 first, then by date:
| Study | Primary completion |
|---|---|
| NCT06765161Phase 3Clinique Neuro-OutaouaisEfgartigimod in IVIG Dependent Myasthenia Gravis Patients | 2027-01-06 |
| NCT04833894Phase 3argenxEvaluating the Pharmacokinetics, Pharmacodynamics, and Safety of Efgartigimod Administered Intravenously in Children With Generalized Myasthenia Gravis | 2027-03 |
| NCT07231523Phase 3Shanghai Zhongshan HospitalEFG vs IVIG in TAMG | 2027-06-01 |
| NCT06392386Phase 3argenxA Study of Efgartigimod PH20 SC in Children Between 2 and Less Than 18 Years of Age With Generalized Myasthenia Gravis | 2027-09 |
| NCT06221501Shanghai Zhongshan HospitalPerioperative Efgartigimod for Thymoma and Myasthenia Gravis | 2026-12-30 |
Add all 7 to your calendar (.ics) → With an account.
Among the 20 studies testing efgartigimod alfa in Myasthenia Gravis, from their registry updates:
Nothing recorded among them since 2026-09-25.
Among argenx’s 18 in Myasthenia Gravis:
Nothing recorded among them since 2026-09-25.
This tab as a report to print or save as PDF → With an account.
The purpose of this study is to measure the pharmacokinetics (PK), pharmacodynamics (PD), safety, tolerability, and immunogenicity of efgartigimod PH20 SC in pediatric participants with gMG aged 2 to \<18 years. The primary goal is to confirm an appropriate dose of efgartigimod PH20 SC for pediatric patients using PK and PD results from this study. Participants will receive injections of efgartigimod PH20 SC and will be monitored for safety until the end of the study. At the end of the follow-up period, eligible participants may roll over to an open-label extension (OLE) study.
The participants will be in the study for up to 14 weeks.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
The complete list of exclusion criteria can be found in the protocol.
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
A weakened immune system. It can come from an illness, such as HIV or some blood cancers, or from medicines that turn the immune system down, for example after an organ transplant or for an autoimmune disease; steroids at higher doses count.
Read whether the line is about a condition or about medicines, and which medicines and doses it means.
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
Vaccines made with a weakened form of the germ, such as measles–mumps–rubella (MMR), chickenpox and yellow fever. They can be risky when the immune system is weakened. Flu injections are not live; the nasal flu spray is.
A condition in which the immune system attacks the body’s own tissues, such as rheumatoid arthritis, lupus, psoriasis, type 1 diabetes or inflammatory bowel disease.
Immunotherapy studies often leave out active autoimmune disease, and some name exceptions, such as thyroid disease on replacement hormone. Check the exceptions this study lists.
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
Hepatitis B is a virus that infects the liver. These are separate tests: HBsAg positive usually means a current infection (a recent vaccination can briefly cause it too); total anti-HBc (HBcAb) positive means an infection now or in the past; HBV DNA measures how much virus is in the blood.
Some studies accept a past infection if HBV DNA is undetectable, sometimes with antiviral medicine during the study. Check what this study allows.
Hepatitis C is a virus that infects the liver. An HCV antibody test can stay positive after an infection has cleared (and is occasionally positive without one); an HCV RNA test shows whether the virus is there now.
After treatment, hepatitis C counts as cured when HCV RNA is still undetectable 12 weeks or more after the treatment ended. Studies often accept people cured this way.
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
The other ingredients in a medicine besides the active drug, such as fillers, colours or preservatives.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Immunosuppression
A weakened immune system. It can come from an illness, such as HIV or some blood cancers, or from medicines that turn the immune system down, for example after an organ transplant or for an autoimmune disease; steroids at higher doses count.
Read whether the line is about a condition or about medicines, and which medicines and doses it means.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Corticosteroids (steroids)
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraception
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Childbearing potential
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Live vaccines
Vaccines made with a weakened form of the germ, such as measles–mumps–rubella (MMR), chickenpox and yellow fever. They can be risky when the immune system is weakened. Flu injections are not live; the nasal flu spray is.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Autoimmune disease
A condition in which the immune system attacks the body’s own tissues, such as rheumatoid arthritis, lupus, psoriasis, type 1 diabetes or inflammatory bowel disease.
Immunotherapy studies often leave out active autoimmune disease, and some name exceptions, such as thyroid disease on replacement hormone. Check the exceptions this study lists.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Cancer (malignancy)
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Clinically significant
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hepatitis B tests
Hepatitis B is a virus that infects the liver. These are separate tests: HBsAg positive usually means a current infection (a recent vaccination can briefly cause it too); total anti-HBc (HBcAb) positive means an infection now or in the past; HBV DNA measures how much virus is in the blood.
Some studies accept a past infection if HBV DNA is undetectable, sometimes with antiviral medicine during the study. Check what this study allows.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hepatitis C tests
Hepatitis C is a virus that infects the liver. An HCV antibody test can stay positive after an infection has cleared (and is occasionally positive without one); an HCV RNA test shows whether the virus is there now.
After treatment, hepatitis C counts as cured when HCV RNA is still undetectable 12 weeks or more after the treatment ended. Studies often accept people cured this way.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
HIV
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hypersensitivity
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Excipients
The other ingredients in a medicine besides the active drug, such as fillers, colours or preservatives.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Participants aged 12 to \<18 years receiving efgartigimod PH20 SC treatment
Biological: Efgartigimod PH20 SC
Drug pages: Efgartigimod alfa · Hyaluronidase (human recombinant)
Subcutaneous injections
Efgartigimod serum concentrations as input for compartmental, model-driven analysis to determine age and size dependency of Clearance (CL)
Time frame: Up to 12 weeks
Efgartigimod serum concentrations as input for compartmental, model-driven analysis to determine age and size dependency of Volume Distribution (Vd)
Time frame: Up to 12 weeks
Total G immunoglobulins (IgG) levels as input for pharmacokinetics (PK)/pharmacodynamics (PD) modelling analysis
Time frame: Up to 12 weeks
Anti-acetylcholine receptors antibodies (AChR-Ab) as input for pharmacokinetics (PK)/ pharmacodynamics (PD) modelling analysis
Time frame: Up to 12 weeks
Incidence of adverse events (AEs)
Time frame: Up to 14 weeks
Severity of adverse events (AEs)
Time frame: Up to 14 weeks
Incidence of serious adverse events (SAEs)
Time frame: Up to 14 weeks
Severity of serious adverse events (SAEs)
Time frame: Up to 14 weeks
Incidence of adverse events of special interest (AESI)
Time frame: Up to 14 weeks
Severity of adverse events of special interest (AESI)
Time frame: Up to 14 weeks
Efgartigimod serum concentrations
Time frame: Up to 12 weeks
Absolute values of total Immunoglobulin G (IgG) from blood samples
Time frame: Up to 12 weeks
Change from baseline values of total Immunoglobulin G (IgG) from blood samples
Time frame: Up to 12 weeks
Percentage change from baseline values of total Immunoglobulin G (IgG) from blood samples
Time frame: Up to 12 weeks
Absolute values of anti-acetylcholine receptor antibodies (AChR-Ab) from blood samples
Time frame: Up to 12 weeks
Change from baseline values of anti-acetylcholine receptor antibodies (AChR-Ab) from blood samples
Time frame: Up to 12 weeks
Percentage change from baseline values of anti-acetylcholine receptor antibodies (AChR-Ab) from blood samples
Time frame: Up to 12 weeks
Incidence of anti-drug antibodies (ADAs) against efgartigimod in serum samples
Time frame: Up to 12 weeks
Prevalence of anti-drug antibodies (ADAs) against efgartigimod in serum samples
Time frame: Up to 12 weeks
Incidence of antibodies against rHuPH20 in serum samples
Time frame: Up to 12 weeks
Prevalence of antibodies against rHuPH20 in serum samples
Time frame: Up to 12 weeks
Absolute value of total Myasthenia Gravis Activity of Daily Living (MG-ADL) score, appropriate for pediatric use
Minimum value: 0 (no impairment); Maximum value: 24 (highest impairment)
Time frame: Up to 12 weeks
Change from baseline of total Myasthenia Gravis Activity of Daily Living (MG-ADL) score, appropriate for pediatric use
Minimum value: 0 (no impairment); Maximum value: 24 (highest impairment)
Time frame: Up to 12 weeks
Absolute value of Quantitative Myasthenia Gravis (QMG) score
Minimum value: 0 (no impairment); Maximum value: 39 (most severe impairment)
Time frame: Up to 12 weeks
Change from baseline of Quantitative Myasthenia Gravis (QMG) score
Minimum value: 0 (no impairment); Maximum value: 39 (most severe impairment)
Time frame: Up to 12 weeks
Absolute value of EuroQoL 5 Dimensions Youth (EQ-5D-Y) score
Time frame: Up to 12 weeks
Change from baseline value of Neuro-QoL Pediatric Fatigue Score
Time frame: Up to 12 weeks
Change from baseline value of EuroQoL 5 Dimensions Youth (EQ-5D-Y) score
Time frame: Up to 12 weeks
Change from baseline value of Clinical Global Impression of Improvement (CGI-I)
Time frame: Up to 12 weeks
Changes in protective antibody titers to vaccines
Time frame: Up to 12 weeks
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Started Jun 2024 (actual). Primary completion is estimated for Sep 2027, 39 months after the start.
How these figures are worked out, and which studies are left out of them.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
Eligibility is decided by the study team. Share this record with your doctor or contact the team directly.
Contact study teamGet an email when the registry record changes — status, dates, results — or when someone posts here.
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Studies of the drugs tested here: Efgartigimod alfa · Hyaluronidase (human recombinant)