Efgartigimod IV for Myasthenia Gravis

(ADAPT Jr Trial)

Recruiting at 84 trial locations

Overseen By Sabine s Coppieters, MD

Age: < 65

Sex: Any

Trial Phase: Phase 2 & 3

Sponsor: argenx

Must be taking: Immunosuppressants, Steroids, AChE inhibitors

Must not be taking: Monoclonal antibodies, IVIg, PLEX

Disqualifiers: MGFA class I, IVb, V, others

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Prior Safety Data This treatment has passed at least one previous human trial

Approved in 2 Jurisdictions This treatment is already approved in other countries

Compensation: Varies

Number of Visits: Unknown

12 Participants Needed

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial tests the effectiveness and safety of efgartigimod, administered through an IV, for children and teens with generalized myasthenia gravis (gMG), a condition that causes muscle weakness. The trial will examine how the body processes the drug and assess symptom improvement over several weeks. It is ideal for those with gMG who do not achieve desired results from current medications. Participants must have a confirmed gMG diagnosis and be on stable treatment. As a Phase 2, Phase 3 trial, this research evaluates the treatment's effectiveness in an initial group and represents the final step before FDA approval, offering participants a chance to contribute to potentially groundbreaking advancements in gMG treatment.

Will I have to stop taking my current medications?

The trial does not specify if you must stop taking your current medications, but it mentions that participants should be on stable gMG therapy before screening. It's best to discuss your current medications with the trial team to understand any specific requirements.

Is there any evidence suggesting that efgartigimod IV is likely to be safe for children and adolescents with myasthenia gravis?

Research has shown that efgartigimod IV, a treatment under study for myasthenia gravis (a condition causing muscle weakness), has been somewhat successful in adults. One study found that about 53% of patients experienced serious outcomes, with hospitalization being the most common. Another study indicated a potential risk of infections for those treated with efgartigimod. Despite these findings, efgartigimod is already approved in several countries for adults with this condition, suggesting it is considered reasonably safe for them.

Since this trial involves children and teenagers, it is important to understand that reactions can vary by age. The trial's current phase provides some safety information, but more research is needed to fully understand its effects on younger patients. ^{1 2 3 4 5}

Why do researchers think this study treatment might be promising for myasthenia gravis?

Researchers are excited about efgartigimod IV for treating Myasthenia Gravis because it offers a novel approach by targeting the neonatal Fc receptor (FcRn). Unlike traditional treatments like cholinesterase inhibitors, immunosuppressants, or corticosteroids, efgartigimod reduces the levels of harmful antibodies by blocking FcRn, which is crucial for prolonging the lifespan of these antibodies in the body. This targeted mechanism could lead to fewer side effects and a more rapid improvement in symptoms, potentially offering a more effective and safer option for patients.

What evidence suggests that efgartigimod IV might be an effective treatment for myasthenia gravis?

Research has shown that efgartigimod IV, which participants in this trial will receive, can significantly help people with generalized myasthenia gravis (gMG). In one study, 84% of patients noticed improvements in their daily activities by the second week. Another study found that patients experienced better muscle strength and daily function for at least four weeks after starting treatment. This treatment proved effective even for those who tested negative for certain antibodies related to the disease. Overall, these findings suggest that efgartigimod IV could be a promising option for managing gMG symptoms. ^{6 7 8 9 10}

Are You a Good Fit for This Trial?

This trial is for children and adolescents aged 2 to less than 18 with Generalized Myasthenia Gravis (gMG). They must have tried other treatments without success, not be pregnant, use contraception consistently, and not have had recent major surgery or certain infections. Those with mild gMG or severe muscle weakness from other causes can't join.

Inclusion Criteria

I agree not to donate sperm during the trial.

I have been diagnosed with Generalized Myasthenia Gravis.

Female participants must have a negative pregnancy test.

Exclusion Criteria

I have had a major surgery or serious disease recently.

I have had, or will have, a thymectomy within 3 months of joining the trial.

You are allergic to efgartigimod or any of its ingredients.

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Treatment Part A

Participants receive efgartigimod IV for dose-confirmatory purposes

8 weeks

Treatment Part B

Participants continue receiving efgartigimod IV for treatment response-confirmatory purposes

18 weeks

Follow-up

Participants are monitored for safety and effectiveness after treatment

2 weeks

What Are the Treatments Tested in This Trial?

Interventions

• Efgartigimod IV

Trial Overview The study tests Efgartigimod IV in young patients with gMG over approximately 28 weeks. It has two parts: an initial dose-confirmatory phase lasting 8 weeks and a subsequent treatment response-confirmatory phase of 18 weeks to assess the drug's effects on their condition.

How Is the Trial Designed?

Group I: Efgartigimod Experimental Treatment 1 Intervention

Patients receiving efgartigimod intravenous (IV) treatment

Efgartigimod IV is already approved in United States, European Union for the following indications:

Approved in United States as Vyvgart for:

• Generalized myasthenia gravis (gMG) in adult patients who are anti-acetylcholine receptor (AChR) antibody positive

Approved in European Union as Vyvgart for:

• Generalized myasthenia gravis (gMG) in adult patients who are anti-acetylcholine receptor (AChR) antibody positive

Approved in United States as Vyvgart Hytrulo for:

• Generalized myasthenia gravis (gMG) in adult patients who are anti-acetylcholine receptor (AChR) antibody positive
• Chronic inflammatory demyelinating polyneuropathy (CIDP)

Who Is Running the Clinical Trial?

argenx

Lead Sponsor

Trials

76

Recruited

11,500+

Tim Van Hauwermeiren

argenx

Chief Executive Officer since 2008

B.Sc. and M.Sc. in Bioengineering from Ghent University, Executive MBA from The Vlerick School of Management

Dr. Peter Ulrichts

argenx

Chief Medical Officer since 2023

MD from Maastricht University, PhD in Molecular Immunology from Maastricht University

Published Research Related to This Trial

Efgartigimod alfa is the first neonatal Fc receptor antagonist approved for treating generalized myasthenia gravis (gMG), showing significant and rapid improvements in muscle strength and quality of life in a phase 3 trial with a placebo group.

The treatment was generally well tolerated, with most side effects being mild to moderate, indicating a favorable safety profile for patients with gMG.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Efgartigimod Alfa in Generalised Myasthenia Gravis: A Profile of Its Use. Heo, YA.[2023]

Efgartigimod, an FcRn antagonist, has been shown in clinical trials to effectively improve clinical status and reduce autoantibody levels in patients with myasthenia gravis, with no significant safety concerns reported.

This treatment has received regulatory approvals in the United States, Japan, and Europe, suggesting its potential effectiveness across various subgroups and severities of myasthenia gravis.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Clinical efficacy and safety of efgartigimod for treatment of myasthenia gravis. Sivadasan, A., Bril, V.[2023]

Efgartigimod, a first-in-class neonatal Fc receptor antagonist, received its first approval in the USA in December 2021 for treating generalized myasthenia gravis in adults who are positive for anti-acetylcholine receptor antibodies.

The drug is also being evaluated for other autoimmune diseases and has been approved in Japan for generalized myasthenia gravis patients regardless of antibody status, indicating its potential broad application in autoimmune conditions.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Efgartigimod: First Approval. Heo, YA.[2022]

In a study of 37 patients with acetylcholine receptor antibody-positive generalized myasthenia gravis, 72% experienced a significant improvement in daily living activities after one cycle of efgartigimod, indicating its efficacy in managing symptoms.

Efgartigimod treatment resulted in a substantial reduction in IgG levels and was generally well-tolerated, with only mild side effects reported, although one patient had to discontinue due to a Clostridium difficile infection.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Safety and outcomes with efgartigimod use for acetylcholine receptor-positive generalized myasthenia gravis in clinical practice. Katyal, N., Halldorsdottir, K., Govindarajan, R., et al.[2023]

Efgartigimod, an engineered antibody, significantly improves muscle function and strength in patients with generalized myasthenia gravis (gMG), as shown by notable enhancements in Myasthenia Gravis Activities of Daily Living (MG-ADL) and Quantitative Myasthenia Gravis (QMG) scores over a 10-week period.

Improvements were observed across all muscle function subdomains (bulbar, ocular, limb/gross motor, and respiratory) within 1 to 2 weeks after the first infusion, correlating with reduced levels of pathogenic IgG, indicating its mechanism of action in decreasing autoantibody levels.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Effect of efgartigimod on muscle group subdomains in participants with generalized myasthenia gravis: post hoc analyses of the phase 3 pivotal ADAPT study. Bril, V., Howard, JF., Karam, C., et al.[2023]

Efgartigimod, a human IgG1 antibody, significantly improved symptoms in patients with generalized myasthenia gravis, with 68% of treated patients showing a meaningful response compared to only 30% in the placebo group, indicating strong efficacy.

The treatment was well tolerated, with similar rates of adverse events between efgartigimod and placebo groups, suggesting it is a safe option for patients, with no deaths reported during the trial.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Safety, efficacy, and tolerability of efgartigimod in patients with generalised myasthenia gravis (ADAPT): a multicentre, randomised, placebo-controlled, phase 3 trial. Howard, JF., Bril, V., Vu, T., et al.[2022]

Efgartigimod was found to be safe and well-tolerated in a phase 2 study involving 24 patients with generalized myasthenia gravis, with no serious adverse events reported.

The treatment led to a significant reduction in pathogenic IgG autoantibodies and resulted in a rapid and long-lasting improvement in disease symptoms for 75% of patients, suggesting its potential as an effective therapy for myasthenia gravis.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Randomized phase 2 study of FcRn antagonist efgartigimod in generalized myasthenia gravis. Howard, JF., Bril, V., Burns, TM., et al.[2020]

Citations

1. argenx.com argenx.com/news/2025/press-release-3176635

argenx Presents New Data at AANEM and MGFA ... “The ADAPT SERON trial showed that efgartigimod generated tangible improvements in daily functioning, marking an important advancement for the ...

2. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC10212825/

Efgartigimod Alfa in Generalised Myasthenia Gravis Among the 44 AChR antibody positive MG-ADL responders in the efgartigimod alfa group, the onset of response occurred by week 2 in 84% of patients, and the ...

3. vyvgarthcp.com vyvgarthcp.com/gmg/clinical-data

Clinical Trial Data - VYVGART Hytrulo Clinical Data · Significantly more patients had improvement in daily function that was sustained for ≥4 weeks · >4x as many patients had reduction in muscle ...

4. rheumatologyadvisor.com rheumatologyadvisor.com/news/efgartigimod-iv-beneficial-in-achr-ab-seronegative-generalized-myasthenia-gravis/

Efgartigimod IV Beneficial in AChR-Ab Seronegative ... Findings showed treatment with efgartigimod IV was associated with a statistically significant and clinically meaningful improvement in MG-ADL ...

5. sciencedirect.com sciencedirect.com/science/article/pii/S2950221724000485

Long-term use of efgartigimod alfa in treating a young adult ... EFG-α may be effective not only for MG but also for SLE, maintaining low disease activity and antibody levels. Long-term use could reduce steroid requirement.

6. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC12041031/

A real-world pharmacovigilance study of efgartigimod alfa ... Myasthenia gravis was the most reported indication (68.52%), and as for reported serious outcomes, hospitalization was the most reported (53.22 ...

7. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC12258281/

Postmarketing adverse events of efgartigimod alfa: a real- ... This study aims to identify adverse event (AE) signals associated with efgartigimod alfa using the Food and Drug Administration Adverse Event ...

8. neurology.org neurology.org/doi/10.1212/WNL.0000000000211132

Infections-related Safety Profile of Efgartigimod Alpha and ... This analysis identified a potential risk of infections in myasthenia gravis patients treated with efgartigimod alfa or immunoglobulins in clinical practice.

9. neurologylive.com neurologylive.com/view/evaluating-risk-clarifying-safety-data-behind-efgartigimod

Clarifying the Safety Data Behind Efgartigimod Josh Bryson, PhD, head of Medical Affairs at Argenx, discussed the safety profile of efgartigimod in light of recent FAERS-based infection data.

10. argenx.com argenx.com/news/2024/argenx-highlights-data-showing-patient-impact-across-multiple-im

argenx Highlights Data Showing Patient Impact Across ... It is the first approved FcRn blocker in the United States, EU, China and Canada for the treatment of adults with generalized myasthenia gravis ...