Abstract Details

Title Long-term Corticosteroid Treatment Patterns and Steroid-sparing Effects of Approved Treatments for Generalized Myasthenia Gravis in the United States

Topic Neuromuscular and Clinical Neurophysiology (EMG)

Presentation(s) C5 - Peripheral Nervous System Autoimmunity (2:28 PM-2:35 PM)
P2 - Poster Session 2 (2:45 PM-3:45 PM)

Poster/Presentation
Number 095

Background Corticosteroids are prevalent in the treatment of gMG despite evidence of adverse effects of long-term corticosteroid use.

Objective To evaluate (1) long-term corticosteroid use patterns in adult patients with generalized myasthenia gravis (gMG) and (2) corticosteroid dose changes after initiating approved biologic treatments for gMG.

Design/Methods A retrospective cohort study was conducted in which patients with gMG were identified in US commercial claims data from January 2016 to September 2023. For Objective 1, descriptive statistics and longitudinal figures were used to describe and illustrate corticosteroid utilization over 24 months of follow-up since first gMG claim. For Objective 2, a multivariable regression model was used to estimate changes in corticosteroid dose pre- and post-initiation of C5 inhibitor therapies (C5iTs; eculizumab, ravulizumab) or a neonatal Fc receptor antagonist (FcRn-a; efgartigimod alfa).

Results Overall, 2237 patients met inclusion criteria comprising three treatment cohorts: no biologic (n=2006); C5iT (n=125); FcRn-a (n=106). Steroid dose journey varied widely, but 454 patients (22.6%) started at doses >10 mg and of those, 194 (42.7%) remained at doses >10 mg at 24 months. In the multivariable analysis, patients had an average reduction in annualized total corticosteroid use of 1562 mg (–36%; p=0.017) following initiation of C5iT and 668 mg (–21%; p=0.08) following initiation of FcRn-a therapy.

Conclusions Steroid use patterns vary widely in adult patients with gMG, but persistent high-dose corticosteroid use is common, despite adverse effects. This study demonstrated that C5iTs facilitated significant steroid sparing within the first year of their initiation.

Authors/Disclosures
Christopher A. Scheiner, MD, PhD (TCNI) PRESENTER	Dr. Scheiner has received personal compensation in the range of $5,000-$9,999 for serving on a Scientific Advisory or Data Safety Monitoring board for Alexion Pharmaceuticals . Dr. Scheiner has received personal compensation in the range of $500-$4,999 for serving on a Scientific Advisory or Data Safety Monitoring board for CSL Behring . Dr. Scheiner has received personal compensation in the range of $500-$4,999 for serving on a Scientific Advisory or Data Safety Monitoring board for Argenx Pharmaceuticals. Dr. Scheiner has received personal compensation in the range of $10,000-$49,999 for serving on a Speakers Bureau for CSL Behring . Dr. Scheiner has received personal compensation in the range of $10,000-$49,999 for serving on a Speakers Bureau for Alexion Pharmaceuticals . The institution of Dr. Scheiner has received research support from Alexion Pharmaceuticals .
Michael Blackowicz, PhD (Alexion)	Dr. Blackowicz has received personal compensation for serving as an employee of Alexion Pharmaceuticals. Dr. Blackowicz has stock in Alexion Pharmaceuticals.
Emma Weiskopf, MD (Alexion Pharmaceuticals)	Dr. Weiskopf has received personal compensation for serving as an employee of Alexion AstraZeneca Rare Disease. Dr. Weiskopf has stock in Alexion Astrazeneca Rare Disease.
Kathryn Clark	No disclosure on file
Jeremy Grant (Definitive healthcare)	No disclosure on file