A Phase 2 interventional study of Empasiprubart IV and Empasiprubart Placebo IV in Guillain-Barré Syndrome (GBS), sponsored by argenx. Not yet recruiting. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-10-28.
Sponsored by argenx · Phase 2, Interventional, and Treatment
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 for the first two weeks, and follow-up through Week 67 (15 months after the last dose of study treatment). Participation lasts up to 67 weeks.
96 studies on the registry are indexed under Guillain-Barre Syndrome; 28 are open to participants now.
This study's planned enrollment of 63 is above the median of 50 across 43 interventional studies indexed under Guillain-Barre Syndrome.
Browse Guillain-Barre Syndrome studies →argenx is the lead sponsor of 87 studies on the registry; 29 are open to participants now.
Of its 22 completed or terminated interventional studies of FDA-regulated products, 16 (73%) have results posted.
Counted across the registry records on this site, refreshed daily.
The criteria were revised on the registry on Oct 28, 2026. See what changed
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
A condition in which the immune system attacks the body’s own tissues, such as rheumatoid arthritis, lupus, psoriasis, type 1 diabetes or inflammatory bowel disease.
Immunotherapy studies often leave out active autoimmune disease, and some name exceptions, such as thyroid disease on replacement hormone. Check the exceptions this study lists.
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
A weakened immune system. It can come from an illness, such as HIV or some blood cancers, or from medicines that turn the immune system down, for example after an organ transplant or for an autoimmune disease; steroids at higher doses count.
Read whether the line is about a condition or about medicines, and which medicines and doses it means.
Autoimmune disease
A condition in which the immune system attacks the body’s own tissues, such as rheumatoid arthritis, lupus, psoriasis, type 1 diabetes or inflammatory bowel disease.
Immunotherapy studies often leave out active autoimmune disease, and some name exceptions, such as thyroid disease on replacement hormone. Check the exceptions this study lists.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Clinically significant
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraindication
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Investigational drug or device
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Immunosuppression
A weakened immune system. It can come from an illness, such as HIV or some blood cancers, or from medicines that turn the immune system down, for example after an organ transplant or for an autoimmune disease; steroids at higher doses count.
Read whether the line is about a condition or about medicines, and which medicines and doses it means.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Participants receive empasiprubart by intravenous infusion and IVIg by intravenous infusion.
Biological: Empasiprubart IV · Biological: Intravenous immunoglobulin (IVIg)
Participants receive placebo by intravenous and IVIg by intravenous infusion.
Other: Empasiprubart Placebo IV · Biological: Intravenous immunoglobulin (IVIg)
Intravenous infusion of Empasiprubart
Intravenous infusion of Placebo
Intravenous infusion of IVIg
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
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 ranges from 0 to 60 and is used to evaluate the severity of weakness and changes in motor function over time. Higher scores indicate better muscle strength/better outcome, while lower scores indicate greater weakness.
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
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.
Time frame: Up to 52 weeks
Actual Inflammatory Rasch-Built Overall Disability Scale (I-RODS) Scores Over Time
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 52 weeks
Actual Overall Neuropathy Limitations Scale (ONLS) Score Over Time
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 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
No study locations are listed for this record.
Plan to share: No
No publications or documents are linked to this record.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
This study is not yet recruiting, as verified in Oct 2026. You cannot join it, but the record below documents what was studied.
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Studies of the drug tested here: Empasiprubart