From the Research
Rituximab is a highly effective treatment option for myasthenia gravis (MG), particularly in patients with muscle-specific kinase (MuSK) antibodies or those with refractory disease, with a recommended low-dose regimen showing improved efficacy and safety compared to conventional dosing. The use of rituximab in MG has been explored in several studies, with the most recent and highest quality study being the 2025 single-arm meta-analysis 1, which demonstrated that low-dose rituximab is more effective than conventional-dose rituximab in achieving minimal manifestation status (MMS) or better, with a higher proportion of patients achieving MMS or better (76.6% vs 51.6%) and a more significant decrease in Quantitative MG Score (QMGs) from baseline (-9.04 vs -3.62).
Key points to consider when using rituximab for MG include:
- The typical dosing regimen for rituximab in MG is not well established, but low-dose regimens (below 375 mg/m²) have shown improved efficacy and safety compared to conventional dosing 1
- Rituximab is especially effective in MuSK-antibody positive MG patients, with response rates of 70-80% 2
- Patients should be aware that clinical improvement may take 1-3 months to become apparent after treatment initiation 2
- Before starting rituximab, patients should be screened for hepatitis B, as the medication can cause reactivation of the virus 2
- Common side effects include infusion reactions, increased risk of infections, and potential long-term effects on immunoglobulin levels 2
The 2022 RINOMAX randomized clinical trial 3 also demonstrated the efficacy and safety of rituximab as an add-on to standard of care for new-onset generalized MG, with a single dose of 500 mg of rituximab associated with a greater probability of minimal MG manifestations and reduced need of rescue medications compared to placebo. However, the 2025 meta-analysis 1 provides the most up-to-date and comprehensive evidence for the use of rituximab in MG, and its findings should be prioritized in clinical decision-making. Overall, rituximab offers a targeted approach to treating MG by addressing the underlying autoimmune mechanism, and its use should be considered in patients with refractory or MuSK-antibody positive disease.