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+)

• ClinicalTrials.gov Identifier: NCT05405361
• Recruitment Status: Recruiting
• First Posted: June 6, 2022
• Last Update Posted: April 9, 2024
• Sponsor: argenx
• Information provided by (Responsible Party): argenx

Tracking Information

• First Submitted Date: May 17, 2022
• First Posted Date: June 6, 2022
• Last Update Posted Date: April 9, 2024
• Actual Study Start Date: January 18, 2023
• Estimated Primary Completion Date: November 1, 2025 (Final data collection date for primary outcome measure)
• Current Primary Outcome Measures (submitted: June 1, 2022): Safety outcomes based on adverse event (AE) monitoring. [ Time Frame: Until marketing authorization of ARGX-117, assessed up to 70 months or treatment discontinuation, whichever comes first ]
• Original Primary Outcome Measures: Same as current

Current Secondary Outcome Measures (submitted: February 28, 2023)

• Value from baseline in the modified Medical Research Council (mMRC) -10 sum score [ Time Frame: On day 1, 8, 15, 22 followed by every 4 weeks during 12 weeks followed by every 8 weeks until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation. ]
  The mMRC sum score evaluates motor strength/weakness from predetermined muscle groups (upper and lower limbs). The higher the score, the better the muscle strength.
• Change from baseline in the modified Medical Research Council (mMRC) -10 sum score [ Time Frame: On day 1, 8, 15, 22 followed by every 4 weeks during 12 weeks followed by every 8 weeks until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation. ]
  The mMRC sum score evaluates motor strength/weakness from predetermined muscle groups (upper and lower limbs). The higher the score, the better the muscle strength
• Proportion of participants showing a deterioration of at least 2 points in Medical Research Council (mMRC)-10 sum score [ Time Frame: On day 1, 8, 15, 22 followed by every 4 weeks during 12 weeks followed by every 8 weeks until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation ]
  The mMRC sum score evaluates motor strength/weakness from predetermined muscle groups (upper and lower limbs). The higher the score, the better the muscle strength.
• Value from baseline in the modified Medical Research Council (mMRC) -14 sum score [ Time Frame: On day 1, 8, 15, 22 followed by every 4 weeks during 12 weeks followed by every 8 weeks until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation. ]
  The mMRC sum score evaluates motor strength/weakness from predetermined muscle groups (upper and lower limbs). The higher the score, the better the muscle strength.
• Change from baseline in the modified Medical Research Council (mMRC) -14 sum score [ Time Frame: On day 1, 8, 15, 22 followed by every 4 weeks during 12 weeks followed by every 8 weeks until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation ]
  The mMRC sum score evaluates motor strength/weakness from predetermined muscle groups (upper and lower limbs). The higher the score, the better the muscle strength.
• Proportion of participants showing a deterioration of at least 2 points in the Medical Research Council (mMRC)-14 sum score [ Time Frame: On day 1, 8, 15, 22 followed by every 4 weeks during 12 weeks followed by every 8 weeks until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation. ]
  The mMRC sum score evaluates motor strength/weakness from predetermined muscle groups (upper and lower limbs). The higher the score, the better the muscle strength.
• Proportion of participants showing a deterioration of 1 or more points in at least 2 muscle groups as assessed by the Medical Research Council (mMRC)-14 sum score [ Time Frame: On day 1, 8, 15, 22 followed by every 4 weeks during 12 weeks followed by every 8 weeks until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation ]
  The mMRC sum score evaluates motor strength/weakness from predetermined muscle groups (upper and lower limbs). The higher the score, the better the muscle strength.
• Proportion of participants with no deterioration in 2 or more muscle groups as assessed by Medical Research Council (mMRC)-14 sum score [ Time Frame: On day 1, 8, 15, 22 followed by every 4 weeks during 12 weeks followed by every 8 weeks until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation. ]
  The mMRC sum score evaluates motor strength/weakness from predetermined muscle groups (upper and lower limbs). The higher the score, the better the muscle strength.
• Value from baseline in the average score of the 2 most important muscle groups as assessed by the Medical Research Council (mMRC)-14 sum score [ Time Frame: On day 1, 8, 15, 22 followed by every 4 weeks during 12 weeks followed by every 8 weeks until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation. ]
  The mMRC sum score evaluates motor strength/weakness from predetermined muscle groups (upper and lower limbs). The higher the score, the better the muscle strength.
• Change from baseline in the average score of the 2 most important muscle groups as assessed by the Medical Research Council (mMRC)-14 sum score [ Time Frame: On day 1, 8, 15, 22 followed by every 4 weeks during 12 weeks followed by every 8 weeks until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation ]
  The mMRC sum score evaluates motor strength/weakness from predetermined muscle groups (upper and lower limbs). The higher the score, the better the muscle strength.
• Values from baseline in grip strength (GS) [ Time Frame: On day 1, 8, 15, 22 followed by every 4 weeks during 12 weeks followed by every 8 weeks until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation. ]
  GS measurement consists of 3 repeated contractions with the participant's maximal effort. The duration of each contraction will be 3 seconds. Each test begins with gripping with the right hand followed by the left. Measurement of GS will be done using the Martin vigorimeter in kPa.
• Change from baseline in grip strength (GS) [ Time Frame: On day 1, 8, 15, 22 followed by every 4 weeks during 12 weeks followed by every 8 weeks until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation ]
  GS measurement consists of 3 repeated contractions with the participant's maximal effort. The duration of each contraction will be 3 seconds. Each test begins with gripping with the right hand followed by the left. Measurement of GS will be done using the Martin vigorimeter in kPa.
• Percent change from baseline in grip strength (GS) [ Time Frame: On day 1, 8, 15, 22 followed by every 4 weeks during 12 weeks followed by every 8 weeks until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation. ]
  GS measurement consists of 3 repeated contractions with the participant's maximal effort. The duration of each contraction will be 3 seconds. Each test begins with gripping with the right hand followed by the left. Measurement of GS will be done using the Martin vigorimeter in kPa.
• Proportion of participants with a decline of >30% in grip strength (GS). [ Time Frame: On day 1, 8, 15, 22 followed by every 4 weeks during 12 weeks followed by every 8 weeks until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation. ]
  GS measurement consists of 3 repeated contractions with the participant's maximal effort. The duration of each contraction will be 3 seconds. Each test begins with gripping with the right hand followed by the left. Measurement of GS will be done using the Martin vigorimeter in kPa.
• Proportion of participants with a grip strength (GS) decrease of 8 kilopascals (kPa) or more. [ Time Frame: On day 1, 8, 15, 22 followed by every 4 weeks during 12 weeks followed by every 8 weeks until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation. ]
  GS measurement consists of 3 repeated contractions with the participant's maximal effort. The duration of each contraction will be 3 seconds. Each test begins with gripping with the right hand followed by the left. Measurement of GS will be done using the Martin vigorimeter in kPa.
• Values from baseline in the Rasch-built overall disability scale for Multifocal Motor Neuropathy (MMN-RODS©). [ Time Frame: On day 1, 8, 15, 22 followed by every 4 weeks during 12 weeks followed by every 8 weeks until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation. ]
  MMN-RODS© consists of 25 items that are scored 0 (unable to perform), 1 (able to perform, but with difficulty), or 2 (able to perform without difficulty) for each item, yielding a total score from 0 to 50.
• Change from baseline in the Rasch-built overall disability scale for Multifocal Motor Neuropathy (MMN-RODS©). [ Time Frame: On day 1, 8, 15, 22 followed by every 4 weeks during 12 weeks followed by every 8 weeks until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation. ]
  MMN-RODS© consists of 25 items that are scored 0 (unable to perform), 1 (able to perform, but with difficulty), or 2 (able to perform without difficulty) for each item, yielding a total score from 0 to 50.
• Values from baseline in the average time for the upper extremity (arm and hand) function (9-Hole Peg Test [9-HPT], or timed pegboard test). [ Time Frame: On day 1, 8, 15, 22 followed by every 4 weeks during 12 weeks followed by every 8 weeks until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation. ]
  The 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).
• Change from baseline in the average time for the upper extremity (arm and hand) function (9-Hole Peg Test [9-HPT], or timed pegboard test). [ Time Frame: On day 1, 8, 15, 22 followed by every 4 weeks during 12 weeks followed by every 8 weeks until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation. ]
  The 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).
• Proportion of participants by level of severity on each dimension of the Euro-Quality of Life 5 Dimensions 5 Levels (EQ-5D-5L) scale. [ Time Frame: On day 1 and 15 followed by every 4 weeks during 12 weeks followed by every 8 weeks until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation. ]
  The descriptive system 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.
• Value from baseline in EQ-5D-5L visual analog scale (VAS). [ Time Frame: On day 1 and 15 followed by every 4 weeks during 12 weeks followed by every 8 weeks until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation. ]
  A vertical 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).
• Change from baseline in EQ-5D-5L visual analog scale (VAS). [ Time Frame: On day 1 and 15 followed by every 4 weeks during 12 weeks followed by every 8 weeks until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation. ]
  A vertical 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).
• Values from baseline in the Chronic Acquired Polyneuropathy Patient-Reported Index (CAP-PRI). [ Time Frame: On day 1 and 15 followed by every 4 weeks during 12 weeks followed by every 8 weeks until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation. ]
  The Chronic Acquired Polyneuropathy Patient-Reported Index (CAP-PRI) includes the assessment of 15 items. Items will be scored 0 (not at all), 1 (a little bit), or 2 (a lot), yielding a total score that ranges from 0 to 30
• Change from baseline in the Chronic Acquired Polyneuropathy Patient-Reported Index (CAP-PRI). [ Time Frame: On day 1 and 15 followed by every 4 weeks during 12 weeks followed by every 8 weeks until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation. ]
  The Chronic Acquired Polyneuropathy Patient-Reported Index (CAP-PRI) includes the assessment of 15 items. Items will be scored 0 (not at all), 1 (a little bit), or 2 (a lot), yielding a total score that ranges from 0 to 30.
• Values from baseline in the 9-item Fatigue Severity Scale (FSS). [ Time Frame: On day 1 and 15 followed by every 4 weeks during 12 weeks followed by every 8 weeks until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation. ]
  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.
• Change from baseline in the 9-item Fatigue Severity Scale (FSS). [ Time Frame: On day 1 and 15 followed by every 4 weeks during 12 weeks followed by every 8 weeks until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation. ]
  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.
• Value change as assessed by the Patient Global Impression of Change (PGIC) scale. [ Time Frame: On day 15 followed by every 4 weeks during 12 weeks followed by every 8 weeks until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation. ]
  PGIC is a 7-point scale depicting a participant's rating of overall improvement. The lower the score, the better the improvement.
• Proportion of participants by level of severity of MMN as assessed by the Patient Global Impression of Severity (PGIS). [ Time Frame: On day 1, 8, 15, 22 followed by every 4 weeks during 12 weeks followed by every 8 weeks until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation. ]
  PGIS is a 7-point scale depicting a participant's rating of overall illness severity. Higher scores mean a higher severity.
• Values for work-related and household chore activities of the Health-Related Productivity Questionnaire (HRPQ). [ Time Frame: On day 1 and 15 followed by every 4 weeks during 12 weeks followed by every 8 weeks until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation. ]
  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.
• Area Under The Curve (AUC). [ Time Frame: On day 1, 8, 15, 22 followed by every 4 weeks during 12 weeks followed by every 8 weeks until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation. ]
• Maximum serum concentrations (Cmax). [ Time Frame: On day 1, 8, 15, 22 followed by every 4 weeks during 12 weeks followed by every 8 weeks until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation. ]
• Values from baseline in free C2, total C2, functional complement activity (CH50). [ Time Frame: On day 1, 8, 15, 22 followed by every 4 weeks during 12 weeks followed by every 8 weeks until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation. ]
• Change from baseline in free C2, total C2, functional complement activity (CH50). [ Time Frame: On day 1, 8, 15, 22 followed by every 4 weeks during 12 weeks followed by every 8 weeks until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation. ]
• Incidence of antidrug antibodies (ADA) against ARGX-117. [ Time Frame: On day 1, 15, 29, 113 followed by every 8 weeks until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation. ]
• Prevalence of antidrug antibodies (ADA) against ARGX-117. [ Time Frame: On day 1, 15, 29, 113 followed by every 8 weeks until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation. ]

Original Secondary Outcome Measures (submitted: June 1, 2022)

• Value from baseline in the modified Medical Research Council (mMRC) -10 sum score [ Time Frame: On day 1, 8, 15, 22 followed by every 4 weeks during 12 weeks followed by every 8 weeks until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation. ]
  The mMRC sum score evaluates motor strength/weakness from predetermined muscle groups (upper and lower limbs). The higher the score, the better the muscle strength.
• Change from baseline in the modified Medical Research Council (mMRC) -10 sum score [ Time Frame: On day 1, 8, 15, 22 followed by every 4 weeks during 12 weeks followed by every 8 weeks until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation. ]
  The mMRC sum score evaluates motor strength/weakness from predetermined muscle groups (upper and lower limbs). The higher the score, the better the muscle strength
• Proportion of participants showing a deterioration of at least 2 points in Medical Research Council (mMRC)-10 sum score [ Time Frame: On day 1, 8, 15, 22 followed by every 4 weeks during 12 weeks followed by every 8 weeks until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation ]
  The mMRC sum score evaluates motor strength/weakness from predetermined muscle groups (upper and lower limbs). The higher the score, the better the muscle strength.
• Value from baseline in the modified Medical Research Council (mMRC) -14 sum score [ Time Frame: On day 1, 8, 15, 22 followed by every 4 weeks during 12 weeks followed by every 8 weeks until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation. ]
  The mMRC sum score evaluates motor strength/weakness from predetermined muscle groups (upper and lower limbs). The higher the score, the better the muscle strength.
• Change from baseline in the modified Medical Research Council (mMRC) -14 sum score [ Time Frame: On day 1, 8, 15, 22 followed by every 4 weeks during 12 weeks followed by every 8 weeks until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation ]
  The mMRC sum score evaluates motor strength/weakness from predetermined muscle groups (upper and lower limbs). The higher the score, the better the muscle strength.
• Proportion of participants showing a deterioration of at least 2 points in the Medical Research Council (mMRC)-14 sum score [ Time Frame: On day 1, 8, 15, 22 followed by every 4 weeks during 12 weeks followed by every 8 weeks until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation. ]
  The mMRC sum score evaluates motor strength/weakness from predetermined muscle groups (upper and lower limbs). The higher the score, the better the muscle strength.
• Proportion of participants showing a deterioration of 1 or more points in at least 2 muscle groups as assessed by the Medical Research Council (mMRC)-14 sum score [ Time Frame: On day 1, 8, 15, 22 followed by every 4 weeks during 12 weeks followed by every 8 weeks until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation ]
  The mMRC sum score evaluates motor strength/weakness from predetermined muscle groups (upper and lower limbs). The higher the score, the better the muscle strength.
• Proportion of participants with no deterioration in 2 or more muscle groups as assessed by Medical Research Council (mMRC)-14 sum score [ Time Frame: On day 1, 8, 15, 22 followed by every 4 weeks during 12 weeks followed by every 8 weeks until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation. ]
  The mMRC sum score evaluates motor strength/weakness from predetermined muscle groups (upper and lower limbs). The higher the score, the better the muscle strength.
• Value from baseline in the 2 most important muscle groups as assessed by the Medical Research Council (mMRC)-14 sum score [ Time Frame: On day 1, 8, 15, 22 followed by every 4 weeks during 12 weeks followed by every 8 weeks until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation. ]
  The mMRC sum score evaluates motor strength/weakness from predetermined muscle groups (upper and lower limbs). The higher the score, the better the muscle strength.
• Change from baseline in the 2 most important muscle groups as assessed by the Medical Research Council (mMRC)-14 sum score [ Time Frame: On day 1, 8, 15, 22 followed by every 4 weeks during 12 weeks followed by every 8 weeks until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation ]
  The mMRC sum score evaluates motor strength/weakness from predetermined muscle groups (upper and lower limbs). The higher the score, the better the muscle strength.
• Values from baseline in grip strength (GS) [ Time Frame: On day 1, 8, 15, 22 followed by every 4 weeks during 12 weeks followed by every 8 weeks until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation. ]
  GS measurement consists of 3 repeated contractions with the participant's maximal effort. The duration of each contraction will be 3 seconds. Each test begins with gripping with the right hand followed by the left. Measurement of GS will be done using the Martin vigorimeter in kPa.
• Change from baseline in grip strength (GS) [ Time Frame: On day 1, 8, 15, 22 followed by every 4 weeks during 12 weeks followed by every 8 weeks until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation ]
  GS measurement consists of 3 repeated contractions with the participant's maximal effort. The duration of each contraction will be 3 seconds. Each test begins with gripping with the right hand followed by the left. Measurement of GS will be done using the Martin vigorimeter in kPa.
• Percent change from baseline in grip strength (GS) [ Time Frame: On day 1, 8, 15, 22 followed by every 4 weeks during 12 weeks followed by every 8 weeks until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation. ]
  GS measurement consists of 3 repeated contractions with the participant's maximal effort. The duration of each contraction will be 3 seconds. Each test begins with gripping with the right hand followed by the left. Measurement of GS will be done using the Martin vigorimeter in kPa.
• Proportion of participants with a decline of >30% in grip strength (GS). [ Time Frame: On day 1, 8, 15, 22 followed by every 4 weeks during 12 weeks followed by every 8 weeks until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation. ]
  GS measurement consists of 3 repeated contractions with the participant's maximal effort. The duration of each contraction will be 3 seconds. Each test begins with gripping with the right hand followed by the left. Measurement of GS will be done using the Martin vigorimeter in kPa.
• Proportion of participants with a grip strength (GS) decrease of 8 kilopascals (kPa) or more. [ Time Frame: On day 1, 8, 15, 22 followed by every 4 weeks during 12 weeks followed by every 8 weeks until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation. ]
  GS measurement consists of 3 repeated contractions with the participant's maximal effort. The duration of each contraction will be 3 seconds. Each test begins with gripping with the right hand followed by the left. Measurement of GS will be done using the Martin vigorimeter in kPa.
• Values from baseline in the Rasch-built overall disability scale for Multifocal Motor Neuropathy (MMN-RODS©). [ Time Frame: On day 1, 8, 15, 22 followed by every 4 weeks during 12 weeks followed by every 8 weeks until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation. ]
  MMN-RODS© consists of 25 items that are scored 0 (unable to perform), 1 (able to perform, but with difficulty), or 2 (able to perform without difficulty) for each item, yielding a total score from 0 to 50.
• Change from baseline in the Rasch-built overall disability scale for Multifocal Motor Neuropathy (MMN-RODS©). [ Time Frame: On day 1, 8, 15, 22 followed by every 4 weeks during 12 weeks followed by every 8 weeks until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation. ]
  MMN-RODS© consists of 25 items that are scored 0 (unable to perform), 1 (able to perform, but with difficulty), or 2 (able to perform without difficulty) for each item, yielding a total score from 0 to 50.
• Values from baseline in the average time for the upper extremity (arm and hand) function (9-Hole Peg Test [9-HPT], or timed pegboard test). [ Time Frame: On day 1, 8, 15, 22 followed by every 4 weeks during 12 weeks followed by every 8 weeks until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation. ]
  The 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).
• Change from baseline in the average time for the upper extremity (arm and hand) function (9-Hole Peg Test [9-HPT], or timed pegboard test). [ Time Frame: On day 1, 8, 15, 22 followed by every 4 weeks during 12 weeks followed by every 8 weeks until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation. ]
  The 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).
• Proportion of participants by level of severity on each dimension of the Euro-Quality of Life 5 Dimensions 5 Levels (EQ-5D-5L) scale. [ Time Frame: On day 1 and 15 followed by every 4 weeks during 12 weeks followed by every 8 weeks until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation. ]
  The descriptive system 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.
• Value from baseline in EQ-5D-5L visual analog scale (VAS). [ Time Frame: On day 1 and 15 followed by every 4 weeks during 12 weeks followed by every 8 weeks until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation. ]
  A vertical 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).
• Change from baseline in EQ-5D-5L visual analog scale (VAS). [ Time Frame: On day 1 and 15 followed by every 4 weeks during 12 weeks followed by every 8 weeks until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation. ]
  A vertical 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).
• Values from baseline in the Chronic Acquired Polyneuropathy Patient-Reported Index (CAP-PRI). [ Time Frame: On day 1 and 15 followed by every 4 weeks during 12 weeks followed by every 8 weeks until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation. ]
  The Chronic Acquired Polyneuropathy Patient-Reported Index (CAP-PRI) includes the assessment of 15 items. Items will be scored 0 (not at all), 1 (a little bit), or 2 (a lot), yielding a total score that ranges from 0 to 30
• Change from baseline in the Chronic Acquired Polyneuropathy Patient-Reported Index (CAP-PRI). [ Time Frame: On day 1 and 15 followed by every 4 weeks during 12 weeks followed by every 8 weeks until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation. ]
  The Chronic Acquired Polyneuropathy Patient-Reported Index (CAP-PRI) includes the assessment of 15 items. Items will be scored 0 (not at all), 1 (a little bit), or 2 (a lot), yielding a total score that ranges from 0 to 30.
• Values from baseline in the 9-item Fatigue Severity Scale (FSS). [ Time Frame: On day 1 and 15 followed by every 4 weeks during 12 weeks followed by every 8 weeks until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation. ]
  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.
• Change from baseline in the 9-item Fatigue Severity Scale (FSS). [ Time Frame: On day 1 and 15 followed by every 4 weeks during 12 weeks followed by every 8 weeks until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation. ]
  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.
• Proportion of participants by level of change as assessed by the Patient Global Impression of Change (PGIC). [ Time Frame: On day 15 followed by every 4 weeks during 12 weeks followed by every 8 weeks until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation. ]
  PGIC is a 7-point scale depicting a participant's rating of overall improvement. The lower the score, the better the improvement.
• Proportion of participants by level of severity of MMN as assessed by the Patient Global Impression of Severity (PGIS). [ Time Frame: On day 1, 8, 15, 22 followed by every 4 weeks during 12 weeks followed by every 8 weeks until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation. ]
  PGIS is a 7-point scale depicting a participant's rating of overall illness severity. Higher scores mean a higher severity.
• Values for work-related and household chore activities of the Health-Related Productivity Questionnaire (HRPQ). [ Time Frame: On day 1 and 15 followed by every 4 weeks during 12 weeks followed by every 8 weeks until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation. ]
  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.
• Area Under The Curve (AUC). [ Time Frame: On day 1, 8, 15, 22 followed by every 4 weeks during 12 weeks followed by every 8 weeks until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation. ]
• Maximum serum concentrations (Cmax). [ Time Frame: On day 1, 8, 15, 22 followed by every 4 weeks during 12 weeks followed by every 8 weeks until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation. ]
• Values from baseline in free C2, total C2, functional complement activity (CH50). [ Time Frame: On day 1, 8, 15, 22 followed by every 4 weeks during 12 weeks followed by every 8 weeks until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation. ]
• Change from baseline in free C2, total C2, functional complement activity (CH50). [ Time Frame: On day 1, 8, 15, 22 followed by every 4 weeks during 12 weeks followed by every 8 weeks until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation. ]
• Incidence of antidrug antibodies (ADA) against ARGX-117. [ Time Frame: On day 1, 15, 29, 113 followed by every 8 weeks until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation. ]
• Prevalence of antidrug antibodies (ADA) against ARGX-117. [ Time Frame: On day 1, 15, 29, 113 followed by every 8 weeks until market authorization of ARGX-117, assessed up to 70 months or treatment discontinuation. ]

• Current Other Pre-specified Outcome Measures: Not Provided
• Original Other Pre-specified Outcome Measures: Not Provided

Descriptive Information

• Brief Title: 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
• Official Title: 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
• Brief Summary: 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.
• Detailed Description: Not Provided
• Study Type: Interventional
• Study Phase: Phase 2

Study Design

Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Triple (Participant, Care Provider, Investigator)
Masking Description:

During the double-blinded rollover treatment period (DTP),the investigator, trial nurse/coordinator, participant, and the sponsor's designated contract research organization (CRO), and sponsor trial team (except the sponsor's clinical trial supplies team) are blinded to IMP. The interactive response technology (IRT) system is used for blinding.

Primary Purpose: Treatment

• Condition: Multifocal Motor Neuropathy (MMN)

Intervention

• Biological: ARGX-117
  Intravenous administration of ARGX-117
• Other: Placebo
  Intravenous administration of placebo

Study Arms

• Experimental: Dose regimen 1
  ARGX-117/Placebo IV
  Interventions:

  • Biological: ARGX-117
  • Other: Placebo
• Experimental: Dose regimen 2 or Dose regimen 3
  ARGX-117/Placebo IV
  Interventions:

  • Biological: ARGX-117
  • Other: Placebo

• Publications *: Not Provided

Recruitment Information

• Recruitment Status: Recruiting
• Estimated Enrollment (submitted: June 1, 2022): 48
• Original Estimated Enrollment: Same as current
• Estimated Study Completion Date: October 1, 2026
• Estimated Primary Completion Date: November 1, 2025 (Final data collection date for primary outcome measure)

Eligibility Criteria

Inclusion Criteria:

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

3. Agrees to use contraceptive measures consistent with local regulations and the following:

   1. Male participants: must use an acceptable contraceptive method that should be maintained at minimum until 15 months after last dose of Investigational Medicinal Product (IMP).
   2. Female participants (women) of childbearing potential must have a negative urine pregnancy test at baseline before Investigational Medicinal Product can be administered.

Exclusion Criteria:

1. Clinically significant uncontrolled active or chronic bacterial, viral, or fungal infection.
2. 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.
3. Currently participating in another interventional clinical study.
4. Pregnant or lactating or intend to become pregnant during the trial or within 15 months after last dose of the Investigational Medicinal Product.

Sex/Gender

• Sexes Eligible for Study: All

• Ages: 18 Years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No

Contacts

Contact: Sabine Coppieters, MD; 857-350-4834; ClinicalTrials@argenx.com

• Listed Location Countries: Austria, Belgium, Canada, France, Germany, Italy, Netherlands, Poland, Spain, United Kingdom, United States

Administrative Information

• NCT Number: NCT05405361
• Other Study ID Numbers: ARGX-117-2003
• Has Data Monitoring Committee: Yes

U.S. FDA-regulated Product

• Studies a U.S. FDA-regulated Drug Product: Yes
• Studies a U.S. FDA-regulated Device Product: No

IPD Sharing Statement

• Plan to Share IPD: No

• Current Responsible Party: argenx
• Original Responsible Party: Same as current
• Current Study Sponsor: argenx
• Original Study Sponsor: Same as current
• Collaborators: Not Provided
• Investigators: Not Provided
• PRS Account: argenx
• Verification Date: April 2024