Efgartigimod PH20 SC treatment for children with generalized Myasthenia Gravis

An Open-label, Uncontrolled Study to Evaluate the Pharmacokinetics, Pharmacodynamics, Safety, and Activity of Efgartigimod PH20 SC in Participants From 2 to Less Than 18 Years of Age With Generalized Myasthenia Gravis

Phase2; Phase3 Interventional argenx · NCT06392386

This study is testing a new injection treatment for children with generalized Myasthenia Gravis to see how well it works and what the right dosage is.

Quick facts

PhasePhase2; Phase3
Study typeInterventional
Enrollment12 (estimated)
Ages2 Years to 17 Years
SexAll
Sponsorargenx Industry-sponsored
Locations20 sites (Charlotte, North Carolina and 19 other locations)
Trial IDNCT06392386 on ClinicalTrials.gov

What this trial studies

This study evaluates the pharmacokinetics, pharmacodynamics, safety, tolerability, and immunogenicity of efgartigimod PH20 SC in pediatric patients aged 2 to less than 18 years with generalized Myasthenia Gravis. Participants will receive injections of the medication and will be monitored for safety over a period of up to 14 weeks. The primary goal is to determine the appropriate dosage for this age group based on the study's findings. Eligible participants may also have the opportunity to continue in an open-label extension study after the initial follow-up.

Who should consider this trial

Good fit: Ideal candidates are children aged 2 to less than 18 years diagnosed with generalized Myasthenia Gravis who have not responded adequately to existing treatments.

Not a fit: Patients who have not been diagnosed with generalized Myasthenia Gravis or those who have not had an unsatisfactory response to current therapies may not benefit from this study.

Why it matters

Potential benefit: If successful, this treatment could provide a new therapeutic option for children suffering from generalized Myasthenia Gravis.

How similar studies have performed: Other studies have shown promise with similar approaches in treating generalized Myasthenia Gravis, indicating potential for success.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* The participant (and/or their legally authorized representative) understands the requirements of the study and is capable of providing written informed consent/assent and complying with protocol requirements
* The participant is aged 2 to \<18 years at the time of informed consent/assent
* The participant has been diagnosed with generalised Myasthenia Gravis that is supported by a physical examination and confirmed seropositivity for anti-acetylcholine receptor antibodies
* The participant has had an unsatisfactory response to immunosuppressants, corticosteroids, or acetylcholinesterase inhibitors but is on stable concomitant MG therapy. If receiving corticosteroids and/or immunosuppressants, must be on a stable dose for ≥1 month before screening
* The participant agrees to use birth control consistent with local regulations and people of child-bearing potential must have a negative blood pregnancy test at screening and a negative urine pregnancy test before receiving the study drug

Exclusion Criteria:

* Is a female adolescent of child-bearing potential who is pregnant and/or lactating or intends to become pregnant during their participation in the study
* Has worsening muscle weakness secondary to a concurrent infection or as a result of a medication
* Has a documented lack of clinical response to plasma exchange (PLEX)
* Received a live or live-attenuated vaccine within \<4 weeks before screening
* Received a thymectomy within 3 months before screening or is planning to get a thymectomy during their participation in the study
* Has a known autoimmune disease or any medical condition that would interfere with an accurate assessment of clinical symptoms of generalised Myasthenia Gravis 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
* Has a positive PCR test for SARS-CoV-2 at screening
* Has/had a clinically significant disease, had recent major surgery (within 3 months of screening) or intends to have major surgery during the study, or has/had any other medical condition that, in the investigator's opinion, would confound the results of the study or put the participant at undue risk
* Has received a different study drug in another clinical study within \<12 before screening
* Is currently participating in another interventional clinical study
* Has previously participated in an efgartigimod clinical study and received at least one dose of study drug
* Has a known hypersensitivity to study drug or any of its excipients
* Has a history of or current episode of alcohol, drug, or medication abuse as assessed by the investigator
* Use of some medications before screening (more information is found in the protocol)

The complete list of exclusion criteria can be found in the protocol.

Where this trial is running

Charlotte, North Carolina and 19 other locations

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Generalized Myasthenia Gravis
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.