EFGARTIGIMOD ALFA for Generalized myasthenia gravis

Inclusion criteria

• {"criterion_text":"- 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.\n- The participant is aged 2 to <18 years at the time of informed consent/assent.\n- The participant has been diagnosed with generalised Myasthenia Gravis that is supported by a physical examination and confirmed seropositivity for anti-acetylcholine receptor antibodies\n- 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.\n- 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

• {"criterion_text":"- 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.\n- Has worsening muscle weakness secondary to a concurrent infection or as a result of a medication.\n- Has a documented lack of clinical response to plasma exchange (PLEX).\n- Received a live or live-attenuated vaccine within <4 weeks before screening.\n- Received a thymectomy within 3 months before screening or is planning to get a thymectomy during their participation in the study.\n- 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.\n- 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\n- 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\n- Has a positive PCR test for SARS-CoV-2 at screening.\n- 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.\n- Has received a different study drug in another clinical study within <12 weeks before screening.\n- Is currently participating in another interventional clinical study.\n- Has previously participated in an efgartigimod clinical study and received at least one dose of study drug.\n- Has a known hypersensitivity to study drug or any of its excipients\n- Has a history of or current episode of alcohol, drug, or medication abuse as assessed by the investigator.\n- 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."}

Primary endpoints

• {"endpoint_text":"- Efgartigimod serum concentrations as input for compartmental, model-driven analysis to determine age and size dependency of CL and Vd\n- PD parameters: total IgG levels and AChR-Ab as input for PK/PD modeling analysis","definition_or_measurement_approach":"Serum efgartigimod concentrations will be used as input for compartmental, model-driven PK analysis to determine clearance (CL) and volume of distribution (Vd) dependency on age and size. PD parameters (total IgG levels and anti-acetylcholine receptor antibodies (AChR-Ab)) will be measured and used as inputs for PK/PD modelling analyses."}

Secondary endpoints

• {"endpoint_text":"- Incidence and severity of adverse events (AEs), including serious AEs and AEs of special interest\n- Changes in vital signs, electrocardiogram (ECGs), and clinical laboratory tests\n- Efgartigimod serum concentrations\n- Total IgG and AChR-Ab levels: absolute values, changes from baseline values, and percent (%) reductions from baseline values","definition_or_measurement_approach":"Safety endpoints assessed as incidence and severity of AEs (including SAEs and AEs of special interest); vital signs, ECGs, and laboratory tests monitored per protocol. Efgartigimod serum concentrations and total IgG / AChR-Ab levels measured at specified timepoints; analyses include absolute values, change from baseline, and percent reductions for PK/PD evaluation."}
• {"endpoint_text":"- Prevalence and incidence of antidrug antibodies (ADA) against efgartigimod and antibodies against rHuPH20\n- Myasthenia Gravis Activities of Daily Living (MG-ADL) total score: absolute value and change from baseline appropriate for pediatric use\n- Quantitative Myasthenia Gravis (QMG): absolute value and change from baseline","definition_or_measurement_approach":"ADA and anti-rHuPH20 antibodies measured in serum to assess immunogenicity. MG-ADL and QMG scores collected to evaluate clinical activity: absolute scores and changes from baseline appropriate for pediatric populations."}
• {"endpoint_text":"- EQ-5D-Y: absolute value and change from baseline\n- Quality of Life in Neurological Disorders Questionnaire (Neuro-QoL) Pediatric Fatigue Score: change from baseline\n- Clinical Global Impression of Improvement (CGI-I): change from baseline\n- Changes in protective antibody titers to vaccines","definition_or_measurement_approach":"Patient-reported outcome measures (EQ-5D-Y, Neuro-QoL pediatric fatigue) and clinician-rated CGI-I assessed at scheduled visits; vaccine antibody titers measured to evaluate effects on protective antibody responses."}

Methods

• Country-specific recruitment arrangements documents (K1) detailing local recruitment procedures (documents available for DE, FR, PL, IT, NL, BE, ES, CZ).
• Study posters, flyers and patient brochures (K2 items) used as recruitment materials (multiple language versions per country).
• Patient study guides and brochures (K2) and study-specific educational materials (e.g., playing cards, study backpack, patient card) to engage participants and families.
• Site-led recruitment via participating hospital/clinic neurology and pediatric neurology departments (site contact details provided in Part II).

France

Earliest CTIS Part Ii Submission Date

27-05-2024

Latest Decision Or Authorization Date

19-06-2025

Processing Time Days

388

Number Of Sites

1

Number Of Participants

1

Czechia

Earliest CTIS Part Ii Submission Date

25-11-2024

Latest Decision Or Authorization Date

20-05-2025

Processing Time Days

176

Number Of Sites

2

Number Of Participants

2

Poland

Earliest CTIS Part Ii Submission Date

01-07-2024

Latest Decision Or Authorization Date

10-06-2025

Processing Time Days

345

Number Of Sites

3

Number Of Participants

3

Germany

Earliest CTIS Part Ii Submission Date

04-07-2024

Latest Decision Or Authorization Date

05-06-2025

Processing Time Days

336

Number Of Sites

1

Number Of Participants

1

Belgium

Earliest CTIS Part Ii Submission Date

02-07-2024

Latest Decision Or Authorization Date

25-06-2025

Processing Time Days

358

Number Of Sites

1

Number Of Participants

1

Spain

Earliest CTIS Part Ii Submission Date

01-07-2024

Latest Decision Or Authorization Date

26-06-2025

Processing Time Days

361

Number Of Sites

1

Number Of Participants

1

Italy

Earliest CTIS Part Ii Submission Date

29-04-2024

Latest Decision Or Authorization Date

14-07-2025

Processing Time Days

441

Number Of Sites

1

Number Of Participants

1

Netherlands

Earliest CTIS Part Ii Submission Date

08-07-2024

Latest Decision Or Authorization Date

11-07-2025

Processing Time Days

368

Number Of Sites

1

Number Of Participants

1

Primary sponsor

Full Name

Argenx

Organisation Type

Pharmaceutical company

Country Of Registered Address

Belgium

Contract research organisations

Name

PPD Development LP

Responsibilities

Clinical operations / vendor management and multiple sponsor duties (codes: 1,11,12,13,15 Vendor management,2,5)

Name

IQVIA Limited

Responsibilities

Responsibilities code 8 (per sponsor duties list)

Name

Endpoint Clinical Inc.

Responsibilities

Responsibilities code 3 (per sponsor duties list)

Third parties

• {"country":"France","full_name":"SGS France","duties_or_roles":"[{\"code\":\"4\"}]","organisation_type":"Pharmaceutical company"}
• {"country":"United States","full_name":"PPD Development LP","duties_or_roles":"[{\"code\":\"1\"},{\"code\":\"11\"},{\"code\":\"12\"},{\"code\":\"13\"},{\"code\":\"15\",\"value\":\"Vendor management\"},{\"code\":\"2\"},{\"code\":\"5\"}]","organisation_type":"Pharmaceutical company"}
• {"country":"Belgium","full_name":"SGS Belgium","duties_or_roles":"[{\"code\":\"10\"},{\"code\":\"13\"},{\"code\":\"5\"},{\"code\":\"6\"},{\"code\":\"7\"}]","organisation_type":"Pharmaceutical company"}
• {"country":"Germany","full_name":"Azenta Germany GmbH","duties_or_roles":"[{\"code\":\"15\",\"value\":\"Long term storage of study samples\"}]","organisation_type":"Pharmaceutical company"}
• {"country":"United States","full_name":"Eresearchtechnology Inc.","duties_or_roles":"[{\"code\":\"15\",\"value\":\"ECG Analysis / review\"}]","organisation_type":"Pharmaceutical company"}
• {"country":"Switzerland","full_name":"Fisher Clinical Services GmbH (Allschwil)","duties_or_roles":"[{\"code\":\"15\",\"value\":\"IMP packaging, labelling, storage and distribution\"}]","organisation_type":"Pharmaceutical company"}
• {"country":"United States","full_name":"Q Squared Solutions LLC","duties_or_roles":"[{\"code\":\"4\"}]","organisation_type":"Laboratory/Research/Testing facility"}
• {"country":"Germany","full_name":"Fisher Clinical Services GmbH (Weil Am Rhein)","duties_or_roles":"[{\"code\":\"15\",\"value\":\"QP release, storage and distribution\"}]","organisation_type":"Pharmaceutical company"}
• {"country":"United States","full_name":"Endpoint Clinical Inc.","duties_or_roles":"[{\"code\":\"3\"}]","organisation_type":"Pharmaceutical company"}
• {"country":"United States","full_name":"Labcorp Central Laboratory Services LP","duties_or_roles":"[{\"code\":\"4\"}]","organisation_type":"Pharmaceutical company"}
• {"country":"Belgium","full_name":"PPD Global Central Labs","duties_or_roles":"[{\"code\":\"4\"},{\"code\":\"5\"},{\"code\":\"6\"}]","organisation_type":"Pharmaceutical company"}
• {"country":"United Kingdom","full_name":"IQVIA Limited","duties_or_roles":"[{\"code\":\"8\"}]","organisation_type":"Pharmaceutical company"}