A Study of Empasiprubart as Add-On Therapy to IVIg in Adult Participants With Guillain-Barré Syndrome

Phase 2Not Yet RecruitingNCT07821762

argenx63 enrolled

Overview

The main purpose of this study is to learn whether empasiprubart, when given in addition to intravenous immunoglobulin (IVIg), helps adults with Guillain-Barré syndrome (GBS) recover and whether it is safe. About 63 participants will be assigned by chance to receive either empasiprubart or placebo by intravenous infusion; all participants will also receive IVIg. The study includes screening for up to 72 hours, study treatment through Day 12, and follow-up through Week 67 (15 months after the last dose of study treatment). Participation lasts up to 67 weeks.

Study Type

INTERVENTIONAL

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

QUADRUPLE

Enrollment

Conditions

Guillain-Barré Syndrome (GBS)

Interventions

Eligibility

Sex: ALLMin age: 18 Years

Medical Language ↔ Plain English

Inclusion Criteria: * At least 18 years old * Clinically diagnosed with Guillain-Barré syndrome (GBS) according to NINDS (National Institute of Neurological Disorders and Stroke) diagnostic criteria * GBS-related weakness beginning within 7 days before the first study treatment * GBS Disability Scale (GBS-DS) score of 3, 4, or 5 at screening and baseline * Was able to walk approximately 10 m or more without assistance before the onset of GBS symptoms * Agrees to receive antibiotic prophylaxis against N. meningitidis and S. pneumoniae for the first 90 days of the study or until a completed vaccination schedule against these bacterial pathogens per local guidelines has been shown. Exclusion Criteria: * History of a previous GBS episode or diagnosis of an atypical GBS variant * Clinical diagnosis of systemic lupus erythematosus (SLE) or known complement deficiency * Autoimmune or neuromuscular diseases or medical conditions (eg, clinically significant renal, hepatic, cardiac, pulmonary, hematologic, or neurological conditions or clinically significant laboratory abnormalities) that would interfere with an accurate assessment of clinical symptoms of GBS, confound the study results, or put the participant at undue risk * IVIg therapy contraindications or another medical condition that, in the opinion of the investigator, would make IVIg administration unsafe * Recent treatment with IVIg or plasma exchange (PLEX), or recent use of certain immune-modulating or immunosuppressive therapies

Outcomes

Primary Outcomes

Proportion of Participants With a Guillain-Barré Syndrome Disability Scale (GBS-DS) Score ≤2 at Week 4

The Guillain-Barré Syndrome Disability Scale (GBS-DS) is a clinician-reported measure of global functional disability. It has 7 categories ranging from 0 (healthy) to 6 (death), with higher scores indicating greater disability. A GBS-DS score ≤2 indicates the participant is able to walk 10 meters or more without assistance.

Time frame: at week 4

Secondary Outcomes

Number of calendar days in the intensive care unit (ICU) within the first 4 weeks of investigational medicinal product (IMP) administration

ICU means intensive care unit; IMP means investigational medicinal product

Time frame: Up to 4 weeks

Number of calendar days receiving invasive mechanical ventilation within the first 4 weeks of investigational medicinal product (IMP) administration

IMP means investigational medicinal product

Time frame: Up to 4 weeks

Time From First Investigational Medicinal Product (IMP) Administration to Achieving a Guillain-Barré Syndrome Disability Scale (GBS-DS) Score ≤2

IMP means investigational medicinal product; The Guillain-Barré Syndrome Disability Scale (GBS-DS) is a clinician-reported measure of global functional disability with 7 categories ranging from 0 (healthy) to 6 (death), with higher scores indicating greater disability.

Time frame: Up to 52 weeks

Actual values in the Inflammatory Rasch-Built Overall Disability Scale (I-RODS) Scores at weeks 13 and 26

The Inflammatory Rasch-Built Overall Disability Scale (I-RODS) is a 24-item participant-reported measure of disability that assesses limitations in activities and social participation. Raw scores range from 0 to 48 and are converted to a centile metric score ranging from 0 (most severe activity and social participation limitations) to 100 (no activity and social participation limitations). Higher scores indicate less disability.

Time frame: Up to 26 weeks

Actual values in the Overall Neuropathy Limitations Scale (ONLS) Score at weeks 13 and 26

The Overall Neuropathy Limitations Scale (ONLS) is a clinician-reported measure of functional limitations in the upper and lower limbs. The upper-limb section is scored from 0 to 5 and the lower-limb section from 0 to 7. A score of 0 indicates no limitations, while scores of 5 (upper limbs) or 7 (lower limbs) indicate no purposeful movement. Higher scores therefore indicate greater functional limitation.

Time frame: Up to 26 weeks

Change from baseline in the Medical Research Council Sum Score (MRC-SS) over time

The Rasch-built Medical Research Council Sum Score (MRC-SS) is a clinician-assessed measure of muscle strength in selected upper and lower extremity muscle groups bilaterally. The resulting score is used to evaluate the severity of weakness and changes in motor function over time, with higher scores reflecting greater muscle strength.

Time frame: Up to 52 weeks

Change from baseline in the Medical Research Council Sum Score (MRC-SS) neck flexion assessment over time

The Rasch-built Medical Research Council Sum Score (MRC-SS) neck flexion assessment evaluates the strength of the neck flexion muscles. The participant is asked to flex the neck (bring the chin toward the chest) while the examiner evaluates muscle strength using a Rasch-modified MRC grading system that ranges from 0 (no visible contraction) to 3 (normal strength).

Time frame: Up to 52 weeks

Change from baseline in the Guillain-Barré Syndrome Disability Scale (GBS-DS) score over time

Time frame: Up to 52 weeks

Actual Inflammatory Rasch-Built Overall Disability Scale (I-RODS) Scores Over Time

Time frame: Up to 52 weeks

Actual Overall Neuropathy Limitations Scale (ONLS) Score Over Time

Time frame: Up to 52 weeks

Number of calendar days receiving invasive mechanical ventilation through week 52

Time frame: Up to 52 weeks

Proportion of participants who require invasive mechanical ventilation over time and at any time through the week 52

Time frame: Up to 52 weeks

Number of calendar days in the Intensive Care Unit (ICU) through week 52

ICU means intensive care unit.

Time frame: Up to 52 weeks

Proportion of participants in the Intensive Care Unit (ICU) over time and at any time through week 52

ICU means intensive care unit.

Time frame: Up to 52 weeks

Number of calendar days from the start of investigational medicinal product (IMP) until discharge from the acute care facility/department

IMP means investigational medicinal product

Time frame: Up to 52 weeks

Number of calendar days from the start of investigational medicinal product (IMP) until discharge from the last rehabilitation unit

IMP means investigational medicinal product

Time frame: Up to 52 weeks

All-cause mortality through week 52

Time frame: Up to 52 weeks

Incidence of Adverse events (AEs) and Adverse Events of Special Interest (AESIs)

AE = adverse event; AESI = adverse event of special interest

Time frame: Up to 67 weeks

Incidence of Serious Adverse Events (SAEs)

SAE = Serious adverse event.

Time frame: Up to 67 weeks

Serum concentrations of empasiprubart over time

Time frame: Up to 52 weeks

Percentage Change From Baseline in Free Complement Component 2 (C2) Over Time

C2 = complement component 2

Time frame: Up to 52 weeks

Percentage Change From Baseline in Total Complement Component 2 (C2) Over Time

C2 = complement component 2

Time frame: Up to 52 weeks

A Study of Empasiprubart as Add-On Therapy to IVIg in Adult Participants With Guillain-Barré Syndrome

Overview

Conditions

Interventions

Eligibility

Outcomes

Primary Outcomes

Secondary Outcomes

Central Contacts