Single-institution experience with efgartigimod in patients with GFAP astrocytopathy: Treatment response and adverse...

Autoimmune glial fibrillary acidic protein astrocytopathy (GFAPA) is a recently recognized autoimmune disorder of the central nervous system. While many patients respond to conventional immunotherapies, a subset exhibits suboptimal responses, highlighting the need for alternative treatment strategies.

To report real-world clinical experience with efgartigimod in GFAPA patients, providing preliminary data on its safety and effectiveness.

This retrospective case-control study was conducted at a single center in China and included patients with GFAPA who received efgartigimod, with a minimum follow-up of 8 weeks.

We analyzed data from 36 patients diagnosed with GFAPA between January 2021 and July 2024. Patients were categorized into two groups: those treated with efgartigimod (n = 16) and those who were not (control group, n = 20). Clinical outcomes were evaluated using the modified Rankin Scale, Clinical Assessment Scale in Autoimmune Encephalitis (CASE), Glasgow Coma Scale (GCS), and assessment of clinical symptoms. Additionally, we monitored treatment-emergent adverse events (TEAEs), changes in cerebrospinal fluid (CSF) parameters (total protein, leukocyte count, anti-GFAP antibody titers), and serum immunoglobulin G (IgG) levels.

Compared to the control group, patients receiving efgartigimod demonstrated greater clinical improvement, as reflected by borderline significant reductions in CASE scores at discharge (p = 0.04). Improvements in GCS scores were also observed at both time points. The efgartigimod group showed significant decreases in CSF total protein, leukocyte count, anti-GFAP antibody titers, and serum IgG levels. The most common TEAEs were mild to moderate infections; no serious safety concerns were identified.

Efgartigimod appears to be safe and potentially effective in patients with GFAPA, and may be associated with improvements in clinical symptoms and neurological function. However, larger prospective, randomized controlled trials are warranted to confirm these findings and establish its role in the treatment algorithm.