Efficacy and safety of rituximab in myasthenia gravis: a French multicentre real‐life study

Abstract

Background and purpose: Fifteen percent of patients with myasthenia gravis (MG) are refractory to conventional treatment. Case reports and a few studies show probable benefit of rituximab in these cases. Our objective was to assess the efficacy and the safety of rituximab in patients with MG, in a multicentric real-life study. Method: Inclusion criteria were: age > 18 years; MG with anti-acetylcholine receptor (AChR) antibodies, anti-muscle-specific kinase (MuSk) antibodies or significant decrement after repetitive nerve stimulation; Myasthenia Gravis Foundation of America (MGFA) class >II; refractory or steroid-dependent MG; and treatment with rituximab. Efficacy was assessed at 6 months using the MGFA-post-intervention status (PIS) score, the myasthenic muscle score (MMS) and the number of patients receiving steroids <10 mg/day. Data on adverse events were collected. Results: Twenty-nine patients were included: 20 with anti-AChR MG, five with anti-MuSK MG and four with seronegative MG. MGFA-PIS score was improved or better (improved, minimal manifestations or remission) in 86.2% of patients after 6 months of treatment (P < 0.0001). The mean MMS increased from 68.8 to 83.1 (P < 0.0001). A decrease in steroid dosage (<10 mg/day) was effective in 57.9% of treated patients. In all, 42.8% of patients experienced adverse events: infections (21.4% of patients); infusion reaction (7%); bradycardia (3.7%); and cytopenia (7%). Conclusion: The present study demonstrates the efficacy and safety of rituximab in patients with MG. Additional studies remain necessary to determine the role of rituximab in the pharmacopeia of MG treatment and to establish precise recommendations for the infusion protocol.

Immunoactive treatment for myasthenia gravis; a Chinese experience

“…The only controlled study of rituximab in MG (BeatMG) reported negative results for the primary study outcome, so far only by abstract 7 . In contrast, several open studies have reported positive results in up to 80% of the patients, 8,9 similar to Zhang et al 1 Retention rates for rituximab in MG have not been communicated until this new Chinese study. However, in MS, rituximab is clearly superior to all other examined treatments regarding maintenance over time.…”

Rituximab for the Treatment of Myasthenia Gravis: A 2021 Update

“…These studies made formal or informal comparisons from before treatment to after treatment and described outcomes in cohorts of patients who all received rituximab. Three studies 18,23,26 were multi-centre, and 6 studies [19][20][21][22]24,25 were conducted at a single centre.…”

“…The non-randomized studies were conducted in Austria, 26 China, 21,24 France, 18 India, 25 Italy, 20 the Republic of Korea, 23 and the US. 19,22…”

Monoclonal Antibodies as Neurological Therapeutics

“…Rituximab is commonly used in refractory cases of myasthenia gravis (MG) in which conventional immunomodulatory therapies have failed, even though evidence suggests that rituximab performs better in new-onset generalized MG than in cases that have become refractory to conventional immunosuppressants [89]. Uncontrolled studies have provided evidence of efficacy in several measures of efficacy such as clinical improvement, time to relapse, reduction in steroid use [90], decrease in antibody titers [91] and reduced inhospital costs in a proportion of MG patients [92][93][94][95][96][97]. The efficacy of rituximab may be more pronounced in anti-Musk Ab MG, in which clinical improvement is associated with significant reduction in anti-Musk Ab titers, even to levels below detection [94,95,97,98].…”