We evaluated outcomes of anti-IL6R therapy in MOGAD, focusing on relapse prevention.

Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) has severe attacks that can be life-threatening and disability accumulates with each attack. Interleukin-6 receptor blockade (anti-IL6R) has shown promise in acute treatment and attack-prevention, though real-world evidence remains limited.

We conducted a single-center observational cohort study including MOGAD patients per 2023 criteria at Mayo Clinic who received anti-IL6R therapy between January 2015 and September 2025. Relapses and adverse events were recorded. Relapse rate prior and after anti-IL6R were assessed.

Twenty-five patients with MOGAD (18 female [72%], median age at onset 34.6 years [IQR 28.2–49.6]) received anti-IL6R therapy (tocilizumab, n=21; satralizumab, n=4) for relapse prevention—either as first-line treatment (n=9), after prior treatment failure (n=12), or due to intolerance to previous therapy (n=4). Eight patients (32%) had concurrent autoimmune diseases; in four with rheumatoid arthritis, anti-IL6R therapy provided dual benefit. Most patients (23/25, 92%) had a relapsing course. Initial attacks included optic neuritis (n=18, 72%), acute disseminated encephalomyelitis (n=4), myelitis (n=2), and cerebral cortical encephalitis (n=1). Before starting anti-IL6R therapy, the median number of attacks was 4 (IQR 2–6) over 2.5 years (IQR 0.8–10.0). During therapy (median duration 1.2 years [IQR 0.6–2.1]), two patients (8%) relapsed. Relapse rate decreased from 1.2 (IQR 0.6–3.3) to 0.0 (IQR 0.0–0.0) attacks/person-year (p<0.001). Any kind of adverse events occurred in 19 patients (76%), and three patients (12%) had a serious infection (that is requiring intravenous antibiotics or hospitalization). Anti-IL6R therapy was discontinued in nine patients (36%): seven for adverse effects, one for persistent disease activity, and one for insurance-related reasons.

Anti-IL6R therapy may be useful for attack-prevention in MOGAD and can be considered as an empiric treatment option while results from prospective, randomized placebo-controlled clinical trials are awaited.