Disease burden among patients with generalized myasthenia gravis in the United States receiving standard of care therapy: the patient perspective

OBJECTIVE: Examination of disease burden experienced by patients with gMG treated with standard of care and not with advanced biologics can inform treatment decision-making. METHODS: A cross-sectional, online survey was completed by adults with generalized myasthenia gravis (gMG; patients self-reported a confirmed diagnosis) in the United States. Patients had received treatment with standard of care (acetylcholinesterase inhibitors, non-steroidal immunosuppressants, corticosteroids, rituximab, immunoglobulins, plasmapheresis) but not advanced biologics (eculizumab, ravulizumab, zilucoplan, efgartigimod, rozanolixizumab, nipocalimab). Responses were compared between patients with mild or moderate/severe gMG (Myasthenia Gravis Activites of Daily Living [MG-ADL] score 0-4 or 5-24). Linear elastic-net regression analysis explored associations between MG-ADL score and selected variables. RESULTS: Overall, 157 eligible patients completed the survey (87.3% female, mean [SD] age 49.5 [14.4] years, mean [SD] time since diagnosis 11.0 [10.9] years). Mean (SD) MG-QoL-15R score was 16.2 (7.2), EQ5D-5L score was 0.6 (0.3), and FACIT-fatigue subscale score was 20.2 (11.3). Overall, 51.6% received additional support/care. Patients with moderate/severe gMG (136/157 [86.6%]) had greater symptom occurence, reduced treatment satisfaction, greater health-related quality of life impairment, and greater support/care needs, compared with patients with mild gMG. In a regression analysis, gMG severity was associated with severity of health-related quality of life impairment (as measured by MG-ADL score and MG-QOL-15R score; coefficient 0.103 [95% CI 0.043, 0.191]). CONCLUSION: Patients in the United States with gMG who are receiving only standard of care report a significant disease burden and impaired quality of life, with greater impairment among patients with severe gMG.