Efgartigimod achieved remission from impending myasthenic crisis in a median of 8 days compared to 12 days with intravenous immunoglobulin, with comparable overall remission rates of approximately 90% in both groups.
- Efgartigimod and IVIg both achieved ~90% remission rates in patients with impending myasthenic crisis
- Efgartigimod worked 4 days faster (8 days vs 12 days median time to remission)
- Both treatments showed similar safety profiles with minimal progression to full crisis
How this compares to prior research
Intravenous immunoglobulin has been a standard treatment for impending myasthenic crisis, typically requiring five days of infusions. Previous research established IVIg\’s efficacy in preventing progression to full crisis requiring mechanical ventilation. Efgartigimod, a newer FcRn antagonist that reduces pathogenic antibodies, had shown promise in stable myasthenia gravis but lacked data in acute crisis situations until this study.
Myasthenia gravis prevalence trends, global data, 1980–1989
Key findings
- Efgartigimod achieved remission in a median of 8 days versus 12 days with IVIg, a statistically significant difference
- Overall remission rates were comparable: 90.48% with efgartigimod and 94.12% with IVIg within one month
- Progression to full myasthenic crisis was rare in both groups, occurring in approximately 5% of patients
What this means in practice
- Ask your neurologist about efgartigimod if you have myasthenia gravis and experience rapidly worsening swallowing or breathing symptoms
- Consider that faster remission may reduce hospital stays and complications in severe myasthenia gravis exacerbations
- If you have acetylcholine receptor antibody-positive myasthenia gravis, note that efgartigimod offers a rapid treatment alternative to IVIg
Frequently asked questions
What is impending myasthenic crisis?
It is a rapid worsening of myasthenia gravis symptoms affecting swallowing or breathing within two weeks, requiring urgent treatment to prevent respiratory failure requiring mechanical ventilation.
How does efgartigimod compare to standard treatment?
Efgartigimod achieved similar remission rates to IVIg but worked significantly faster, reducing time to remission by four days on average.
Is efgartigimod safe for myasthenia gravis patients?
In this study, efgartigimod showed no treatment-emergent adverse events and had a similar safety profile to IVIg, with minimal progression to full crisis.
Key terms explained
Impending myasthenic crisis
Rapid worsening of myasthenia gravis affecting swallowing or breathing that may progress to respiratory failure within days or weeks
Acetylcholine receptor antibody
Autoantibodies that attack neuromuscular junctions, blocking nerve signals to muscles and causing myasthenia gravis symptoms
FcRn antagonist
A drug that blocks the receptor responsible for recycling antibodies, thereby reducing levels of disease-causing autoantibodies in the blood
Source: Efficacy and safety of efgartigimod in the treatment of impending myasthenic crisis. · DOI: doi: 10.3389/fimmu.2026.1760953