A Clinical Trial to Investigate the Long-term Safety and Tolerability, Efficacy, Pharmacodynamics, Pharmacokinetics, and Immunogenicity of ARGX-117 in Adults With Multifocal Motor Neuropathy (ARDA+)

A Long-term Extension of the ARGX-117-2002 Trial to Evaluate the Long-term Safety and Tolerability, Efficacy, Pharmacodynamics, Pharmacokinetics, and Immunogenicity of ARGX-117 in Adults With Multifocal Motor Neuropathy

This trial is an extension of the antecedent trial ARGX-117-2002. It is a multicenter trial that has been designed to evaluate the long-term safety and tolerability, efficacy, immunogenicity, Pharmacokinetics (PK), and Pharmacodynamics (PD) of ARGX-117 Intravenously (IV) in adults with Multifocal Motor Neuropathy (MMN). The trial will include a double-blinded rollover treatment period (DTP), an open-label treatment period (OTP), and a safety follow-up period.

Study Overview

• Status: Active, not recruiting
• Conditions: Multifocal Motor Neuropathy (MMN)
• Intervention / Treatment: Biological: ARGX-117; Other: Placebo

• Study Type: Interventional
• Enrollment (Actual): 51
• Phase: Phase 2

Contacts and Locations

Study Locations

• Austria
  • Vienna, Austria, 1090
    • Medizinische Universität Wien (Medical University of Vienna)
• Belgium
  • Ghent, Belgium, 9000
    • AZ Sint-Lucas
• Canada
  • Toronto, Canada
    • University Health Network
• France
  • Bordeaux, France, 33076
    • CHU Bordeaux - Groupe Hospitalier Pellegrin
  • Lille, France, 59037
    • Hôpital Roger Salengro (CHU de Lille)
  • Nice, France, 06001
    • CHU de Nice
  • Paris, France, 75651
    • Hôpital de la Pitié Salpêtrière
• Germany
  • Essen, Germany, 45147
    • Universitätsklinikum Essen
  • Göttingen, Germany, 37075
    • Universitatsmedizin Gottingen (UMG) Georg-August-Universitaet
• Italy
  • Milan, Italy, 20132
    • IRCCS Ospedale San Raffaele S.r.l.
  • Pisa, Italy, 56126
    • Azienda Ospedaliero Universitaria Pisana
  • Rome, Italy, 00189
    • Azienda Ospedaliera Sant' Andrea
  • Rozzano, Italy, 20089
    • IRCCS Humanitas Research Hospital
• Netherlands
  • Utrecht, Netherlands, 3584 CX
    • Universitair Medisch Centrum Utrecht
• Poland
  • Krakow, Poland, 31-426
    • Michalski i Partnerzy Lekarze Spolka Partnerska
  • Warsaw, Poland, 02-097
    • Warszawski Uniwersytet Medyczny
• Spain
  • Barcelona, Spain, 08035
    • Hospital Universitario Vall d'Hebron
  • Barcelona, Spain, 08041
    • Hospital De La Santa Creu I Sant Pau
  • Valencia, Spain, 46026
    • Hospital Universitari i Politecnic La Fe de Valencia
• United Kingdom
  • Glasgow, United Kingdom, G51 4TF
    • Queen Elizabeth University Hospital
  • Oxford, United Kingdom, OX3 9DU
    • Oxford University Hospitals NHS Trust
• United States
  • Arizona
    • Scottsdale, Arizona, United States, 85251
      • HonorHealth Neurology
  • Illinois
    • Glenview, Illinois, United States, 60026
      • Northshore University Healthsystem
  • Minnesota
    • Minneapolis, Minnesota, United States, 55414
      • University of Minnesota
  • Ohio
    • Cleveland, Ohio, United States, 44195
      • The Cleveland Clinic Foundation
  • Pennsylvania
    • Philadelphia, Pennsylvania, United States, 19104
      • University of Pennsylvania - Perelman Center for Advanced Medicine
  • Texas
    • Austin, Texas, United States, 78759
      • Austin Neuromuscular Center

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Capable of providing signed informed consent and complying with protocol requirements. Participants must be able to read and write.
• Must have completed the double-blinded treatment period of the ARGX-117-2002 trial and considered to be eligible for treatment with ARGX-117.

Exclusion Criteria:

• Clinically significant uncontrolled active or chronic bacterial, viral, or fungal infection.
• Clinical evidence of other significant serious diseases, have had a recent major surgery, or who have any other condition, in the opinion of the investigator, that could confound the results of the trial or put the participant at undue risk.
• Currently participating in another interventional clinical study.
• Pregnant or lactating or intend to become pregnant during the trial or within 15 months after last dose of the study drug.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Triple

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: ARGX-117; Participants receiving ARGX-117 during the double-blinded treatment period (DTP) and the open-label treatment period (OLTP)	Biological: ARGX-117; Intravenous administration of ARGX-117
Experimental: Placebo; Participants receiving placebo during the double-blinded treatment period (DTP) and receiving ARGX-117 during the open-label treatment period (OLTP)	Biological: ARGX-117; Intravenous administration of ARGX-117; Other: Placebo; Intravenous administration of placebo

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Safety outcomes based on adverse event (AE) monitoring.	Until marketing authorization of ARGX-117, assessed up to 70 months or treatment discontinuation, whichever comes first

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change from baseline in the mMRC-10 sum score	The modified Medical Research Council (mMRC) sum score evaluates motor strength/weakness from predetermined muscle groups (upper and lower limbs). The higher the score, the better the muscle strength	Until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation, whichever comes first
Proportion of participants showing a deterioration of at least 2 points in mMRC-10 sum score	The modified Medical Research Council (mMRC) sum score evaluates motor strength/weakness from predetermined muscle groups (upper and lower limbs). The higher the score, the better the muscle strength.	Until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation, whichever comes first
Change from baseline in the mMRC-14 sum score	The modified Medical Research Council (mMRC) sum score evaluates motor strength/weakness from predetermined muscle groups (upper and lower limbs). The higher the score, the better the muscle strength.	Until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation, whichever comes first
Proportion of participants showing a deterioration of at least 2 points in the mMRC-14 sum score	The modified Medical Research Council (mMRC) sum score evaluates motor strength/weakness from predetermined muscle groups (upper and lower limbs). The higher the score, the better the muscle strength.	Until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation, whichever comes first
Change from baseline in the average score of the 2 most important muscle groups as assessed by the mMRC-14 sum score	The modified Medical Research Council (mMRC) sum score evaluates motor strength/weakness from predetermined muscle groups (upper and lower limbs). The higher the score, the better the muscle strength.	Until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation, whichever comes first
Change from baseline in GS	The grip strength (GS) will be measured by using a Martin-Vigorimeter. Each GS measurement will consist of 3 repeated contractions with the participant's maximal effort. The duration of each contraction will be 3 seconds. 3 repetitions will be executed consecutively by the right hand followed by 3 repetitions of the left hand. There will be a 30-second rest period between each of the 3 repetitions and a 2-minute rest period between each hand.	Until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation, whichever comes first
Proportion of participants with a decline of >30% in GS	The grip strength (GS) will be measured by using a Martin-Vigorimeter. Each GS measurement will consist of 3 repeated contractions with the participant's maximal effort. The duration of each contraction will be 3 seconds. 3 repetitions will be executed consecutively by the right hand followed by 3 repetitions of the left hand. There will be a 30-second rest period between each of the 3 repetitions and a 2-minute rest period between each hand.	Until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation, whichever comes first
Change from baseline in the MMN-RODS	The Rasch-Built Overall Disability Scale for MMN (MMN-RODS) is a disease specific patient-reported outcome instrument constructed specifically to capture activity limitations in patients with MMN. The total score varies between 0 (worst outcome) and 50 (best outcome).	Until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation, whichever comes first
Change from baseline in the average time for the upper extremity (arm and hand) function (9-HPT, or timed pegboard test)	The 9-Hole Peg Test (9-HPT) is a quantitative measure of upper extremity (arm and hand) function. Both the dominant and nondominant hands will be tested twice (2 consecutive trials of the dominant hand, followed immediately by 2 consecutive trials of the nondominant hand).	Until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation, whichever comes first
Proportion of participants by level of severity on each dimension of the EQ-5D-5L	The Euro-Quality of Life 5 Dimensions 5 Levels (EQ-5D-5L) comprises 5 dimensions: mobility, self-care, usual activities, pain/discomfort, and anxiety/depression. Scores for each dimension include 5 levels: no problem, slight problem, moderate problem, severe problem, and extreme problem.	Until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation, whichever comes first
Change from baseline in EQ-5D-5L visual analog scale (VAS)	A vertical visual analog scale (VAS) is included in the EQ-5D-5L. Participants mark their health status from 0 (the worst health you can imagine) to 100 (the best health you can imagine).	Until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation, whichever comes first
Change from baseline in the CAP-PRI	The Chronic Acquired Polyneuropathy Patient-Reported Index (CAP-PRI) includes the assessment of 15 items. The total score varies between 0 (best outcome) and 30 (worst outcome)	Until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation, whichever comes first
Change from baseline in the 9-item FSS	In the 9-item Fatigue Severity Scale (FSS) fatigue levels are rated from 1 to 7. A low value indicates that the statement is not very appropriate whereas a high value indicates agreement.	Until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation, whichever comes first
Values of the PGIC scale	The Patient Global Impression of Change (PGIC) is a 7-point scale depicting a participant's rating of overall improvement. The lower the score, the better the improvement.	Until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation, whichever comes first
Proportion of participants by level of severity of MMN as assessed by PGIS	The Patient Global Impression of Severity (PGIS) is a 7-point scale depicting a participant's rating of overall illness severity. Higher scores mean a higher severity.	Until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation, whichever comes first
Values for work-related and household chore activities of the HRPQ	The Health-Related Productivity Questionnaire (HRPQ) provides data related to missed hours at work or educational activities and reduced effectiveness during any attempted work. These criteria form an important portion of work-related productivity and will be used to assess health-related and work-related productivity in the trial.	Until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation, whichever comes first
Serum concentrations for ARGX-117		Until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation, whichever comes first
Change from baseline in free C2, total C2, functional complement activity (CH50).		Until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation, whichever comes first
Incidence of antidrug antibodies (ADA) against ARGX-117		Until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation, whichever comes first

Collaborators and Investigators

• Sponsor: argenx

Study record dates

Study Major Dates

• Study Start (Actual): January 18, 2023
• Primary Completion (Estimated): September 30, 2029
• Study Completion (Estimated): September 30, 2029

Study Registration Dates

• First Submitted: May 17, 2022
• First Submitted That Met QC Criteria: June 1, 2022
• First Posted (Actual): June 6, 2022

Study Record Updates

• Last Update Posted (Actual): March 11, 2026
• Last Update Submitted That Met QC Criteria: March 9, 2026
• Last Verified: March 1, 2026

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Nervous System Diseases; Neuromuscular Diseases; Peripheral Nervous System Diseases; Neuritis
• Other Study ID Numbers: ARGX-117-2003; 2023-507052-69-00 (Ctis)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No