IVIg and Plasma Exchange Show Comparable Functional Outcomes in Guillain-Barre Syndrome

A large prospective observational analysis drawn from the International GBS Outcome Study (IGOS) found no statistically significant difference in functional outcomes between patients with Guillain-Barre syndrome (GBS) treated with intravenous immunoglobulin (IVIg) versus plasma exchange (PE) after multivariable adjustment.¹

The findings, featured in a poster at the 2026 Peripheral Nerve Society (PNS) Annual Meeting in Maastricht, Netherlands add real-world observational weight to the longstanding clinical consensus that both therapies produce comparable outcomes, while also highlighting meaningful baseline differences between patients who receive each treatment in practice.

Study Design

Led by Anmol Rajpar, MSc, of the Department of Neurology at Erasmus MC University Medical Center in Rotterdam, Netherlands, the analysis drew on data from the IGOS, a prospective, observational study enrolling patients with confirmed GBS across 21 countries worldwide, with a total cohort of 2,000 patients. The current analysis included 1,420 patients who received either IVIg or PE and had available outcome data.

The primary analysis investigated the difference in GBS disability score (GBS-DS) at 4 and 26 weeks from study entry between treatment groups. Multivariable ordinal regression was used, adjusting for age, baseline MRC sum score, preceding diarrhea, GBS-DS at inclusion, time from onset of weakness to treatment, GBS variant at inclusion, and country of inclusion.¹

Key Findings

Of the 1,420 patients analyzed, 1,227 (86%) received IVIg and 193 (14%) received PE. Age was comparable between groups (median 54 years, IQR 37 to 67 for IVIg versus median 55 years, IQR 40 to 65 for PE). However, patients treated with PE had lower MRC sum scores at entry (median 42, IQR 38 to 55) compared with those receiving IVIg (median 48, IQR 32 to 52; P < .05), suggesting that PE was preferentially used in more severely affected patients.¹

The proportion of patients treated with PE varied substantially by country, ranging from 0.83% in the Netherlands to 63.4% in China, underscoring how geographic and institutional factors drive treatment selection independent of disease severity. Patients in the PE group also had a longer median time from onset of weakness to treatment (median 6 days, IQR 3 to 8) versus those receiving IVIg (median 4 days, IQR 2 to 7; P < .05).¹

After multivariable ordinal regression adjusting for these differences, no significant difference in GBS-DS was found at week 4 (OR 0.74, 95% CI 0.51 to 1.05) or week 26 (OR 0.79, 95% CI 0.54 to 1.15) between groups.¹ The investigators concluded that functional outcomes are comparable for patients receiving IVIg and PE after accounting for important confounding factors, with further analyses to be presented at the meeting.

Clinical Context

The equivalence of IVIg and PE in GBS has been established through randomized trials and Cochrane meta-analyses dating to the 1990s, with both therapies shown to hasten recovery compared with supportive care alone.^2,3 Current AAN guidelines recommend both as first-line options for patients with severe or early GBS, with IVIg generally preferred due to its more favorable side effect profile and ease of administration.⁴ Despite this established equivalence, up to 20% of patients treated with either therapy are unable to walk at 6 months, and nearly 5% die, highlighting the persistent unmet need for more effective treatments.⁵

The IGOS dataset is one of the largest prospective GBS registries ever assembled, and its multinational scope allows for the kind of real-world confounding adjustment that single-center retrospective studies cannot achieve. The wide variation in PE use by country observed in this analysis reflects both resource availability and historical practice patterns, factors that are difficult to disentangle from clinical decision-making even in large observational datasets.

Limitations

As an observational study, IGOS cannot fully account for unmeasured confounders driving treatment selection, particularly given the significant baseline differences in disease severity between groups. The substantially smaller PE group (n = 193) relative to IVIg (n = 1,227) may limit statistical power to detect differences. Further subgroup analyses planned for the PNS meeting presentation may clarify outcomes in high-severity patients or specific GBS variants.

Click here for more PNS 2026 coverage.

REFERENCES
1. Rajpar A, de Jong S, van Doorn PA, Querol L, Jacobs B, Wiegers E. Efgartigimod versus plasma exchange in Guillain-Barre syndrome: a real-world comparative efficacy and safety study. Abstract submitted to: Peripheral Nerve Society Annual Meeting; 2026; Maastricht, Netherlands.
2. Hughes RAC, Swan AV, van Doorn PA. Intravenous immunoglobulin for Guillain-Barre syndrome. Cochrane Database Syst Rev. 2014;(9):CD002063. doi:10.1002/14651858.CD002063.pub6. https://doi.org/10.1002/14651858.CD002063.pub6
3. Chevret S, Hughes RAC, Annane D. Plasma exchange for Guillain-Barre syndrome. Cochrane Database Syst Rev. 2017;(2):CD001798. doi:10.1002/14651858.CD001798.pub3. https://doi.org/10.1002/14651858.CD001798.pub3
4. American Academy of Neurology. Immunotherapy for Guillain-Barre syndrome: guideline summary for clinicians. Accessed June 13, 2026. https://www.aan.com/Guidelines/home/GetGuidelineContent/115
5. Stino AM, Doyle MF, Ha C, et al. Intravenous immunoglobulin and plasma exchange prescribing patterns for Guillain-Barre syndrome in the United States, 2001 to 2018. Muscle Nerve. 2024;70(5):876-884. doi:10.1002/mus.28265. https://doi.org/10.1002/mus.28265