The share of MS patients in Sweden who are treated with rituximab is very high, and also rapidly increasing. Taken into account the off-label use, cases with adverse medical conditions that could possibly be related to rituximab use should be reported thoroughly.

ImportanceRituximab is a third-line option for refractory generalized myasthenia gravis (MG) based on empirical evidence, but its effect in new-onset disease is unknown.ObjectiveTo investigate the efficacy and safety of rituximab compared with placebo as an add-on to standard of care for MG.Design, Setting, and ParticipantsThis randomized, double-blind, placebo-controlled study took place throughout 48 weeks at 7 regional clinics in Sweden. Key inclusion criteria were age older than 18 years, onset of generalized symptoms within 12 months or less, and a Quantitative Myasthenia Gravis (QMG) score of 6 or more. Patients were screened from October 20, 2016, to March 2, 2020. Key exclusion criteria included pure ocular MG, suspected thymoma, previous thymectomy, and prior noncorticosteroid immunosuppressants or high doses of corticosteroids.InterventionsParticipants were randomized 1:1 without stratification to a single intravenous infusion of 500 mg of rituximab or matching placebo.Main Outcomes and MeasuresMinimal disease manifestations at 16 weeks defined as a QMG score of 4 or less with prednisolone, 10 mg or less daily, and no rescue treatment.ResultsOf 87 potentially eligible patients, 25 were randomized to rituximab (mean [SD] age, 67.4 [13.4] years; 7 [28%] female) and 22 to placebo (mean [SD] age, 58 [18.6] years; 7 [32%] female). Compared with placebo, a greater proportion with rituximab met the primary end point; 71% (17 of 24) in the rituximab group vs 29% (6 of 21) in the placebo group (Fisher exact test P = .007; probability ratio, 2.48 [95% CI, 1.20-5.11]). Secondary end points, comparing changes in Myasthenia Gravis Activities of Daily Living and Myasthenia Gravis Quality of Life at 16 weeks with QMG at 24 weeks did not differ between groups with censoring for rescue treatment (per-protocol analysis) but were in favor of active treatment when rescue treatment was taken into account by worst rank imputation (post hoc analysis). Rescue treatments were also more frequent in the placebo arm (rituximab: 1 [4%]; placebo, 8 [36%]). One patient in the placebo arm had a myocardial infarction with cardiac arrest and 1 patient in the active arm experienced a fatal cardiac event.Conclusions and RelevanceA single dose of 500 mg of rituximab was associated with greater probability of minimal MG manifestations and reduced need of rescue medications compared with placebo. Further studies are needed to address long-term benefit-risk balance with this treatment.Trial RegistrationClinicalTrials.gov Identifier: NCT02950155

Objectives:To describe Myasthenia Gravis-Activities of Daily Living (MG-ADL) in relation to clinical characteristics in a large Swedish nationwide cohort.Methods:In a cross-sectional prevalent cohort study, the Genes and Environment in Myasthenia Gravis study (GEMG), performed November 2018 - August 2019, Myasthenia gravis (MG) patients were invited to submit an extensive 106-item life environment questionnaire, including the MG-ADL score. Patients were classified into early onset MG (EOMG, <50 years), late onset MG (LOMG, ≥50 years) or thymoma-associated MG (TAMG). Comparisons of disease-specific characteristics were made between subgroups, sex and different MG-ADL scores.Results:A total of 1077 patients were included, yielding a 74% response rate: 505 (47%) were classified as EOMG, 520 (48%) LOMG and 45 (4%) TAMG. Mean age at inclusion was 64.3 years (SD 15.7) and mean disease duration was 14.6 years (SD 14.0). Complete MG-ADL scores (n=1035) ranged from 0-18p, where 26% reported a score of 0p. Higher MG-ADL scores were associated with female sex, obesity and diagnostic delay (OR=1.62, 1.72 and 1.69, Padj=0.017, 0.013 and 0.008) and inversely correlated with high educational attainment (OR=0.59, Padj=0.02), but not with age at inclusion, disease subtype nor disease duration. Almost half the population (47%) reported MG-ADL ≥3p, corresponding to an unsatisfactory symptom state.Conclusions:In this nationwide study, comprising more than 40% of the prevalent MG population in Sweden, we observe that almost half of patients report current disease symptoms associated to an unsatisfactory symptom state, indicating the need for improved treatment options.