Efgartigimod for Myasthenia Gravis

(ADAPT NXT Trial)

No longer recruiting at 42 trial locations

Overseen By Antonio Guglietta, MD

Age: 18+

Sex: Any

Trial Phase: Phase 3

Sponsor: argenx

Must not be taking: IVIg, Rituximab, Eculizumab, others

Disqualifiers: Infections, Autoimmune diseases, Cancer, others

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

Pivotal Trial (Near Approval) This treatment is in the last trial phase before FDA approval

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

Approved in 4 Jurisdictions This treatment is already approved in other countries

Compensation: Varies

Number of Visits: 5

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial examines the effects of efgartigimod, a treatment for Generalized Myasthenia Gravis (gMG), a condition that causes muscle weakness. The researchers aim to compare two different dosing schedules to determine which is more effective and better tolerated. The trial is open to individuals diagnosed with gMG, particularly those experiencing symptoms like muscle weakness or difficulty with daily activities. Participants can expect a combination of weekly and less frequent visits throughout the trial. As a Phase 3 trial, this study represents the final step before FDA approval, offering participants an opportunity to contribute to the potential availability of a new treatment.

Will I have to stop taking my current medications?

You may not need to stop your current medications for Generalized Myasthenia Gravis, as the trial allows certain treatments like nonsteroidal immunosuppressive drugs, steroids, and acetylcholinesterase inhibitors if they are stable for at least a month before screening. However, some specific treatments like intravenous immunoglobulin, rituximab, and eculizumab must be stopped for a certain period before starting the trial.

Is there any evidence suggesting that efgartigimod is likely to be safe for humans?

Research has shown that efgartigimod is generally well-tolerated by people with generalized myasthenia gravis (gMG). Studies have identified the most common side effects as respiratory infections, headaches, and urinary tract infections. There is also an increased risk of infections and some allergic reactions.

The FDA has already approved efgartigimod for treating gMG, indicating a certain level of established safety. However, individual reactions can vary, and ongoing studies continue to provide more information. Discuss any concerns with a healthcare provider. ^{1 2 3 4 5}

Why are researchers excited about this trial's treatment for Myasthenia Gravis?

Researchers are excited about efgartigimod for myasthenia gravis because it offers a novel approach to treatment. Unlike standard therapies that often rely on immunosuppressants, efgartigimod works by targeting and reducing the levels of pathogenic IgG antibodies, which are key players in the disease's progression. This targeted mechanism is expected to provide relief with potentially fewer side effects. Additionally, efgartigimod can be administered intravenously in both continuous and cyclic regimens, offering flexibility in treatment scheduling that could improve patient convenience and adherence.

What evidence suggests that efgartigimod might be an effective treatment for Myasthenia Gravis?

Research has shown that efgartigimod offers promising results for treating generalized Myasthenia Gravis (gMG). In this trial, participants will receive efgartigimod through different intravenous regimens. Studies have found that patients can perform daily activities more easily, with improvements measured by a score reflecting better muscle function. Efgartigimod lowers the number of antibodies that mistakenly attack the body's muscles. Previous studies confirmed its effectiveness and tolerability. Overall, efgartigimod is considered a strong option for helping those with gMG. ^{6 7 8 9 10}

Are You a Good Fit for This Trial?

Adults diagnosed with Generalized Myasthenia Gravis (gMG) who have muscle weakness and are positive for anti-acetylcholine receptor antibodies. Participants must be able to consent, follow study procedures, and use contraception if applicable. Excluded are those with serious diseases, recent major surgery, pregnancy or lactation, certain prior treatments including efgartigimod itself, active infections including COVID-19, other autoimmune diseases that could interfere with the study or pose a risk.

Inclusion Criteria

Capable of giving signed informed consent, which includes compliance with the requirements and restrictions listed in the informed consent form (ICF) and in this protocol

My daily activities are significantly affected by my Myasthenia Gravis symptoms.

I have been diagnosed with gMG and tested positive for AChR antibodies.

Exclusion Criteria

You have had a bad reaction to efgartigimod or any of its ingredients before.

You have another autoimmune disease that might make it hard to understand the symptoms of the condition being studied or put you at risk.

Previous participation in a clinical study or patient access program during which they were treated with efgartigimod

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Regimen Comparison

Participants receive either a continuous or cyclic regimen of efgartigimod to evaluate efficacy, safety, and tolerability

21 weeks

Weekly visits (including virtual)

Extension

Participants continue treatment to further assess long-term efficacy and safety

up to 105 weeks

Every 5 weeks (including virtual)

Follow-up

Participants are monitored for safety and effectiveness after treatment

up to 9 weeks

What Are the Treatments Tested in This Trial?

Interventions

• Efgartigimod

Trial Overview The trial is testing Efgartigimod IV's effectiveness in two dosing regimens: continuous versus cyclic. It aims to determine which regimen offers better efficacy while assessing safety over a period of up to 138 weeks. The first part compares regimens over 21 weeks; the second extends treatment up to an additional 105 weeks.

How Is the Trial Designed?

Group I: Efgartigimod IV - cyclic regimen Experimental Treatment 1 Intervention

Participants receiving efgartigimod IV on a cyclic regimen

Group II: Efgartigimod IV - continuous regimen Experimental Treatment 1 Intervention

Participants receiving efgartigimod IV on a continuous regimen

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

Approved in European Union as Vyvgart for:

• Generalized Myasthenia Gravis (gMG)

Approved in United States as Vyvgart for:

• Generalized Myasthenia Gravis (gMG)
• Chronic Inflammatory Demyelinating Polyneuropathy (CIDP)

Approved in Canada as Vyvgart for:

• Generalized Myasthenia Gravis (gMG)

Approved in Japan as Vyvgart for:

• Generalized Myasthenia Gravis (gMG)

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, 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, 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 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, 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 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 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 ... These positive results in MG-ADL score mean patients experienced significant improvements in one or a combination of their abilities in ...

2. uspharmacist.com uspharmacist.com/article/study-vyvgart-yields-positive-results-in-myasthenia-gravis-patients

Vyvgart Yields Positive Results in Myasthenia Gravis Patients Study: Vyvgart Yields Positive Results in Myasthenia Gravis Patients. Recently, argenx announced positive topline data from the pivotal phase ...

3. clinicaltrials.gov clinicaltrials.gov/study/NCT02965573

NCT02965573 | A Study to Evaluate the Safety, Efficacy, ... A Study to Evaluate the Safety, Efficacy, and Pharmacokinetics of ARGX-113 in Patients With Myasthenia Gravis Who Have Generalized Muscle Weakness.

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

Efgartigimod Alfa in Generalised Myasthenia Gravis Efgartigimod alfa is a novel, effective and generally well-tolerated treatment option for patients with gMG.

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

Clinical Trial Data - VYVGART Hytrulo The ADAPT trial established the effectiveness of VYVGART for IV infusion in the treatment of gMG in adults who are anti-AChR antibody positive.

6. accessdata.fda.gov accessdata.fda.gov/drugsatfda_docs/label/2024/761195s004,761304s003lbl.pdf

VYVGART® (efgartigimod alfa-fcab) injection, for intravenous ... The safety of immunization with live vaccines and the immune response to vaccination during treatment with VYVGART are unknown. Because VYVGART causes a ...

7. vyvgarthcp.com vyvgarthcp.com/gmg/safety

Safety - VYVGART Hytrulo The most common adverse reactions for VYVGART-treated patients were respiratory tract infection, headache, and urinary tract infection.

8. vyvgart.com vyvgart.com/gmg

VYVGART (efgartigimod alfa-fcab) for IV infusion and ... VYVGART and VYVGART Hytrulo may increase the risk of infection and can cause allergic, infusion or injection-related reactions. The most common side effects ...

9. clinicaltrials.gov clinicaltrials.gov/study/NCT03770403

A Safety and Tolerability Study of ARGX-113 in Patients ... This is a Long-Term, Single-Arm, Open-Label, Multicenter Phase 3 follow-on trial of the ARGX-113-1704 study to evaluate the safety and tolerability of ...

10. aetna.com aetna.com/cpb/medical/data/1000_1099/1002.html

Efgartigimod Alfa-fcab (Vyvgart) and ... Safety, efficacy, and tolerability of efgartigimod in patients with generalised myasthenia gravis (ADAPT): A multicentre, randomised, placebo-controlled ...