Assessing the symptom control provided by ravulizumab or efgartigimod in myasthenia gravis: an evaluation of the patient experience of two different treatment approaches

Abstract

Objective: To introduce patient-centric perspectives of symptom control using a novel modeling approach to estimate time spent in health states for the generalized myasthenia gravis (gMG) therapies ravulizumab (terminal complement inhibitor) and efgartigimod (neonatal Fc receptor antagonist). Methods: Myasthenia Gravis Activities of Daily Living (MG-ADL), Quantitative Myasthenia Gravis (QMG), and Myasthenia Gravis Quality of Life 15-item revised (MG-QOL15r) scores were extracted from the phase 3 CHAMPION MG (ravulizumab; seven time points) and ADAPT (efgartigimod; nine time points) trials and compared with the preceding score to define health states of improving, stable, or worsening, with extrapolation to 1 year. Stable state was evaluated across threshold ranges of 0.2–1.0-point change between observations. The proportion of time spent across health states was calculated for each stability threshold and then averaged for an overall summary across the range of cut points. Results: When extrapolated to 1 year, patients receiving ravulizumab spent more time with stable symptoms compared with patients on efgartigimod as measured by MG-ADL, QMG, and MG-QOL15r across stability thresholds. On average, patients receiving ravulizumab spent more time in stable or improving health states combined according to MG-ADL, QMG, MG-QOL15r (100%, 91%, and 79% of the year, respectively) compared to worsening states (0%, 9%, 21%). Patients receiving efgartigimod also spent more time, on average, stable or improving (83%, 75%, 77%) than worsening (17%, 25%, 23%). Variation in symptom control was smaller with ravulizumab than with efgartigimod. Conclusions: In this analysis, fixed-dose ravulizumab treatment was associated with stable symptom control in patients with gMG, whereas treatment with variable-dose efgartigimod resulted in initial improvement but more variable symptom control over time. Patients’ personal goals and quality-of-life should be considered when choosing a gMG therapy.