Myasthenia Gravis: Cochrane Review on Benefits and Harms of Immunoglobulin
Intravenous immunoglobulins do not appear to be much more effective than placebo and are less effective than plasmapheresis in treating myasthenia gravis. This is suggested by a Cochrane review of twelve controlled studies. However, the quality of the studies is rather limited.
Key messages
- Intravenous immunoglobulin may slightly improve symptoms and the ability to carry out daily activities in people with myasthenia gravis. However, the effects may not be large enough to matter to patients.
- Compared to plasma exchange intravenous immunoglobulin may be less beneficial in improving symptoms and may prolong hospital stay, but we are not confident in the evidence for these results.
- Intravenous immunoglobulin probably causes headache in up to one-third of patients and may lead to the breakdown of red blood cells, though it is unclear whether this would make a real difference to patients’ health.
- For many results, we have little or no confidence in the evidence due to limited data and study quality, highlighting the need for further well‑designed studies.
Objectives
To assess the benefits and harms of immunoglobulin in people with generalized MG. Specifically, we aimed to compare 1) intravenous immunoglobulin (IVIg) versus subcutaneous immunoglobulin (SCIg), and 2) immunoglobulin administered via either route (irrespective of treatment duration, dosage, and regimen) versus no treatment, placebo, plasma exchange (PLEX), corticosteroids, acetylcholinesterase inhibitors, or any other treatment.
We wanted to find out if immunoglobulin provides more benefit than other treatments, , in reducing physician-assessed disease symptoms, and improving patients' ability to carry out daily activities.
We also investigated whether immunoglobulin affects length of hospital stay, leads to myasthenia gravis-related hospitalizations, and causes specific treatment-related unwanted effects, such as hypotension (low blood pressure), headache or breakdown of red blood cells.
What did we do?
On 17 September 2024, we searched the Cochrane Neuromuscular's Specialised Register, Cochrane Central Register of Controlled Trials, MEDLINE, Embase, and ClinicalTrials.gov. We also searched the World Health Organization's International Clinical Trials Registry Platform to May 2022. Additionally, we reviewed the references of included studies.
We searched for studies comparing immunoglobulin to other treatments in people who still had symptoms despite receiving other therapies, including only those that randomly assigned people to treatment groups.
What did we find?
We included 12 studies with 515 people conducted in Europe, North America, and Asia between 1997 and 2025. All studies evaluated IVIg; no studies evaluated subcutaneous immunoglobulin.
IVIg versus placebo: IVIg may slightly improve physician-assessed symptoms and self-reported ability to carry out daily activities for up to six months, though the effects may not be large enough to matter to patients, but we have little confidence in the evidence. We are moderately confident that IVIg probably causes headache in up to one-third of patients. It may lead to the breakdown of red blood cells, though it is unclear whether this would make a real difference to patients’ health, and we have little confidence in the evidence. IVIg may not change the length of hospital stay, but we are not confident in the evidence for this. It may also not lead to more myasthenia gravis‑related hospitalizations, but again, we have little confidence in the evidence.
IVIg versus plasma exchange: IVIg may be less beneficial than plasma exchange in improving physician-assessed symptoms, but both treatments may improve self-reported ability to carry out daily activities to a similar degree in the first two weeks. However, we are not confident in the evidence for these results. IVIg may also lead to longer hospital stays than plasma exchange, but we have little confidence in the evidence. The two treatments may not differ in their unwanted effects, but again, we are not confident in the evidence.
IVIg versus corticosteroids: IVIg and corticosteroids may not differ in physician-assessed symptom improvement in the first two weeks, but we are not confident in the evidence. No evidence was available for other outcomes.
IVIg versus subcutaneous immunoglobulin: no studies evaluated subcutaneous immunoglobulin or compared it to IVIg or other treatments.
What are the limitations of the evidence?
Our confidence in the evidence was reduced due to limited data, concerns about how people were assigned to treatments, and because many outcomes were only reported by one study. There was no evidence evaluating subcutaneous immunoglobulin or its comparison to IVIg or plasma exchange. We also found no usable data for many outcomes we had planned to study.
Authors' conclusions
We found low-certainty evidence that IVIg may improve symptoms and functional capacity in the medium term in people with MG, compared to placebo, though the effects did not reach commonly used thresholds for clinical significance and were based on sensitivity analyses. Based on moderate-certainty evidence, IVIg probably also increases the incidence of headache. Based on very low to low-certainty evidence, IVIg may be less beneficial than PLEX for short-term improvement in symptoms and may prolong hospital stay, though we found no differences in adverse events. No firm conclusions can be drawn for the comparison of IVIg with corticosteroids. Overall, due to the low or very low certainty of evidence, high-quality trials are needed, including evaluations of SCIg and newer therapies.
Source: Cochrane