CHICAGO — Satralizumab (Enspryng), a humanized monoclonal antibody, was associated with a significant reduction in relapse risk compared with placebo in myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD), results from the phase 3 METEOROID trial show.

In what investigators say is the first randomized controlled trial to show positive outcomes in this patient population, participants receiving satralizumab had a 68% reduced risk for a new MOGAD relapse compared with those receiving placebo, and a greater percentage of the group remained relapse-free at 48 weeks.

Additionally, risk reductions for annualized relapse rate and active lesions rate were 66% and 78.5%, respectively, in the satralizumab vs placebo groups.

“If this gets approved, it would be a major breakthrough for patients with MOGAD,” chair of the study’s worldwide steering committee Friedemann Paul, MD, Charité-Universitätsmedizin Berlin and Max Delbrueck Center for Molecular Medicine, Berlin, Germany, told Medscape Medical News.

The findings were presented on April 21 at American Academy of Neurology (AAN) 2026 Annual Meeting.

Unmet Need

MOGAD is a demyelinating autoimmune disease of the central nervous system that can result in persistent neurologic and visual disability.

The condition, which has no approved therapy, is commonly treated with off-label medications, such as IV immunoglobulins and oral immunosuppressants. Corticosteroids are also often prescribed during a relapse.

Satralizumab, a humanized monoclonal antibody designed to block the interleukin-6 receptor, received FDA approval in 2020 for the treatment of aquaporin-4 immunoglobulin G-positive neuromyelitis optica spectrum disorder (NMOSD), often considered a “cousin” condition to MOGAD.

The drug’s anti-inflammatory properties and efficacy in NMOSD made it an attractive candidate for MOGAD, coordinating principal investigator for the US Michael Levy, MD, PhD, associate professor of neurology at Harvard Medical School, Boston, told Medscape Medical News.

For the double-blind, randomized controlled METEROID trial, the investigators enrolled 132 patients who were at least 12 years of age at baseline and had relapsing MOGAD, defined as one or more relapses in the previous 12 months or at least two attacks in the previous 24 months.

The treatment group (n = 68; mean age, 41.5 years; 50% women) received subcutaneous injections of satralizumab at baseline, at weeks 2 and 4, and every 4 weeks thereafter. Other participants (n = 64; mean age, 41.2 years; 69% women) received matching placebo plus immunosuppressive therapy. An open-label period of about 24 months followed.

The primary outcome was time to first relapse. Key secondary outcomes included safety, relapse rate, active MRI lesions, and the need for rescue therapy and hospitalization.

Primary Endpoint: Met

Results showed prolonged time to first relapse, resulting in a significant risk reduction for a new MOGAD relapse in the satralizumab group vs the placebo group (hazard ratio, 0.32; P = .00025) and meeting the study’s primary endpoint.

Adjudicated relapse was reported in 13% of satralizumab-treated participants vs 38% in placebo-treated participants. More patients were relapse free in the satralizumab group than the placebo group at 48 weeks (87% vs 67%) and at 96 weeks (84% vs 54%).

Participants receiving satralizumab also had a 66% risk reduction in annualized relapse rate (P = .003), a 79% reduction in annualized rate of active lesions (P = .003), and a 73% reduction in need for rescue therapy (P = .002) compared with those receiving placebo.

The overall number of reported hospitalizations was low, with no significant difference between groups.

Among the satralizumab and placebo groups, 85% vs 84% experienced adverse events (AEs), 11.8% vs 6.3% had serious AEs, and 56% vs 75% had infections. There was one instance of an AE leading to dose discontinuation in the novel drug group.

This safety profile was similar to what was reported with satralizumab in NMOSD trials, investigators said.

‘A Game Changer’

The findings demonstrate how immune modulation can improve neurologic outcomes, Paul M. George, MD, PhD, Department of Neurology and Neurological Sciences at Stanford Medicine, Palo Alto, California, and AAN Science Committee chair, told Medscape Medical News.

“Any time we have a good-quality phase 3 trial, it offers excitement to be able to treat patients; and in this case, those with MOGAD,” he said.

George, who was not involved with the research, added that it would be “a game changer” if this drug were to receive FDA approval, specifically because “there is currently no directed therapy for MOGAD available.”

Investigators said the manufacturer, Roche/Genentech, plans to submit applications to the FDA, the EMA, and to authorities in Japan.

The study was funded by Roche/Genentech. Paul reported having served as a paid consultant, on a Scientific Advisory or Data Safety Monitoring board, and/or on a Speakers Bureau for Roche and several other organizations including Alexion, Novartis, and Sanofi. Levy reported serving as paid consultant for and on scientific advisory boards for Genentech/Roche and other organizations including Alexion and Horizon. George reported serving as a consultant for ConductiveBio and as a adjudicator with Baim Institute.