Efficacy and Safety of Rituximab for New-Onset Generalized Myasthenia Gravis: The RINOMAX Randomized Clinical Trial.

Importance: Rituximab is a third-line option for refractory generalized myasthenia gravis (MG) based on empirical evidence, but its effect in new-onset disease is unknown. Objective: To investigate the efficacy and safety of rituximab compared with placebo as an add-on to standard of care for MG. Design, Setting, and Participants: This 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. Interventions: Participants were randomized 1:1 without stratification to a single intravenous infusion of 500 mg of rituximab or matching placebo. Main Outcomes and Measures: Minimal 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. Results: Of 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 Relevance: A 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 Registration: ClinicalTrials.gov Identifier: NCT02950155.

Safety and efficacy of rituximab versus dimethyl fumarate in patients with relapsing-remitting multiple sclerosis or clinically isolated syndrome in Sweden: a rater-blinded, phase 3, randomised controlled trial.

BACKGROUND: B-cell depleting therapies are highly efficacious in relapsing-remitting multiple sclerosis but one such therapy, rituximab, is not approved for multiple sclerosis and no phase 3 trial data are available. We therefore examined the safety and efficacy of rituximab compared with dimethyl fumarate in patients with relapsing-remitting multiple sclerosis to obtain data that might allow inclusion of rituximab in treatment guidelines. METHODS: RIFUND-MS was a multicentre, rater-blinded, active-comparator, phase 3, randomised controlled trial done at 17 Swedish university and community hospitals. Key inclusion criteria for participants were: age 18-50 years; relapsing-remitting multiple sclerosis or clinically isolated syndrome according to prevailing McDonald criteria; 10 years or less since diagnosis; untreated or only exposed to interferons or glatiramer acetate; and with clinical or neuroradiological disease activity in the past year. Patients were automatically randomly assigned (1:1) by the treating physician using a randomisation module in the Swedish multiple sclerosis registry, without stratification, to oral dimethyl fumarate 240 mg twice daily or to intravenous rituximab 1000 mg followed by 500 mg every 6 months. Relapse evaluation, Expanded Disability Status Scale rating, and assessment of MRI scans were done by examining physicians and radiologists masked to treatment allocation. The primary outcome was the proportion of patients with at least one relapse (defined as subacute onset of new or worsening neurological symptoms compatible with multiple sclerosis with a duration of more than 24 h and preceded by at least 30 days of clinical stability), assessed in an intention-to-treat analysis using log-binomial regression with robust standard errors. This trial is registered at ClinicalTrials.gov, NCT02746744. FINDINGS: Between July 1, 2016, and Dec 18, 2018, 322 patients were screened for eligibility, 200 of whom were randomly assigned to a treatment group (100 assigned to rituximab and 100 assigned to dimethyl fumarate). The last patient completed 24-month follow-up on April 21, 2021. 98 patients in the rituximab group and 97 patients in the dimethyl fumarate group were eligible for the primary outcome analysis. Three (3%) patients in the rituximab group and 16 (16%) patients in the dimethyl fumarate group had a protocol-defined relapse during the trial, corresponding to a risk ratio of 0·19 (95% CI 0·06-0·62; p=0·0060). Infusion reactions (105 events [40·9 per 100 patient-years]) in the rituximab group and gastrointestinal reactions (65 events [47·4 per 100 patient-years]) and flush (65 events [47·4 per 100 patient-years]) in the dimethyl fumarate group were the most prevalent adverse events. There were no safety concerns. INTERPRETATION: RIFUND-MS provides evidence that rituximab given as 1000 mg followed by 500 mg every 6 months is superior to dimethyl fumarate in preventing relapses over 24 months in patients with early relapsing-remitting multiple sclerosis. Health economic and long-term safety studies of rituximab in patients with multiple sclerosis are needed. FUNDING: Swedish Research Council.

Patient-Reported Symptom Severity in a Nationwide Myasthenia Gravis Cohort: Cross-sectional Analysis of the Swedish GEMG Study.

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, P adj=0.017, 0.013 and 0.008) and inversely correlated with high educational attainment (OR=0.59, P adj=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.

Pharmacokinetics of levetiracetam during pregnancy, delivery, in the neonatal period, and lactation.

PURPOSE: To study pharmacokinetics of levetiracetam (LEV) during pregnancy, delivery, lactation, and in the neonatal period. METHODS: Fourteen women with epilepsy receiving LEV treatment during pregnancy and lactation contributed with 15 pregnancies to this prospective study in which LEV concentrations in plasma and breast milk were determined. Trough maternal plasma samples were collected each trimester, and at baseline after delivery. Blood samples were obtained at delivery from mothers, from the umbilical cord, and from newborns during 2 days after delivery. LEV concentration was also determined in breast milk and in plasma collected from 11 of the mothers and their suckling infants after birth. RESULTS: The umbilical cord/maternal plasma concentration ratios ranged from 0.56-2.0 (mean 1.15, n=13). LEV plasma concentrations in the neonates declined with an estimated half-life of 18 h (n=13). The mean milk/maternal plasma concentration ratio was 1.05 (range, 0.78-1.55, n=11). The infant dose of LEV was estimated to 2.4 mg/kg/day, equivalent to 7.9% of the weight-normalized maternal dose. Plasma concentrations in breastfed were approximately 13% of the mother's plasma levels. Maternal plasma concentrations during third trimester were only 40% of baseline concentrations outside pregnancy (p<0.001, n=7) CONCLUSIONS: Our observations suggest considerable transplacental transport of LEV and fairly slow elimination in the neonate. Plasma concentrations of LEV in nursed infants are low despite an extensive transfer of LEV into breast milk. Pregnancy appears to enhance the elimination of LEV resulting in marked decline in plasma concentration, which suggests that therapeutic monitoring may be of value.