P.056 Real-world reduction in oral corticosteroid utilization following efgartigimod initiation in patients with generalized myasthenia gravis

Abstract

Background: Reducing oral corticosteroids (OCS) use can alleviate the risk of many adverse events related to long-term OCS use. Here, we evaluate real-world utilization of OCS among patients with generalized myasthenia gravis (gMG) over the first 6 months following efgartigimod initiation. Methods: Patients with gMG using OCS who initiated efgartigimod treatment were identified retrospectively from an open US medical and pharmacy claims database (IQVIA Longitudinal Access and Adjudication Data [LAAD], April 2016-April 2023). Average daily dose (ADD) of OCS was analyzed during the 3-month period preceding efgartigimod initiation, and at 3 and 6 months post-efgartigimod initiation. Results: Of 231 patients assessed, 17 (7.4%), 109 (47.1%), and 105 (45.5%) had baseline OCS ADD of 0–5 mg, 5–20 mg, or >20 mg, respectively. At 3 and 6 months post-efgartigimod, 82 (35%) and 99 (43%) patients, respectively, reduced ADD by ≥5 mg. Proportion of patients with ADD of 0–5 mg increased >3-fold (7% baseline vs. 26% 6 months post-efgartigimod) and proportion of patients with ADD of >20 mg decreased by 35% (45% baseline vs. 29% 6 months post-efgartigimod) following efgartigimod initiation. Conclusions: Approximately 43% of patients were able to decrease steroid use or achieved steroid-free status within 6 months of efgartigimod treatment initiation.