FDA Priority Review Puts Satralizumab on Track as First MOGAD Drug

The FDA has granted priority review to satralizumab (Enspryng; Roche/Genentech) for myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD), a rare autoimmune CNS disorder for which no treatments are currently approved. If approved, satralizumab would become the first and only disease-modifying therapy for MOGAD, with an FDA decision expected by January 10, 2027.¹

The supplemental biologics license application is based on results from the phase 3 METEOROID study (NCT05271409), in which satralizumab met its primary end point of time to first adjudicated MOGAD relapse. The European Medicines Agency has separately validated a corresponding application, with a European Commission decision anticipated in the third quarter of 2027.

MOGAD is estimated to affect between 0.51 and 3.42 per 100,000 people and causes relapsing attacks on the optic nerves, brain, and spinal cord that can result in vision loss, weakness, and accumulating disability. The condition currently has no FDA-approved treatments, leaving clinicians reliant on off-label immunosuppressive therapies and high-dose steroids to manage relapses.

In the absence of an approved therapy, MOGAD has traditionally been managed with the same tools used for other relapsing CNS autoimmune diseases. Acute attacks are typically treated with high-dose intravenous corticosteroids, often followed by plasma exchange or intravenous immunoglobulin in patients with an incomplete response. For relapse prevention, clinicians have relied on off-label maintenance immunosuppression, most commonly rituximab, azathioprine, mycophenolate mofetil, or long-term intravenous immunoglobulin, none of which carry an indication specific to MOGAD and all of which are used based on extrapolation from related conditions and observational data rather than randomized trial evidence in this population.

METEOROID is a randomized, double-blind, placebo-controlled, event-driven phase 3 trial that enrolled adults and adolescents 12 years and older with relapsing MOGAD, concluding after 28 adjudicated relapses had occurred across the study population.^3,4 Findings were first presented at the 2026 American Academy of Neurology Annual Meeting.³

In the study, satralizumab reduced the risk of a first adjudicated relapse by 68% compared with placebo (P = .0025), meeting the trial's primary end point, with the treatment effect emerging as early as week 8.^1,2 At 48 weeks, 87% of satralizumab-treated patients remained relapse-free, compared with 67% of patients receiving placebo. Annualized relapse rate was reduced by 66% versus placebo (P = .0030), and active MRI lesion activity across the optic nerves, brain, and spinal cord was reduced by 79% in the annualized rate.²

The proportion of patients requiring rescue therapy, defined as steroids, plasma exchange, or intravenous immunoglobulin, was 73% lower with satralizumab (P = .0024). Inpatient hospitalizations were numerically reduced by 17%, though this difference was not statistically significant (P = .7528). The treatment benefit was reported as consistent across subgroups defined by age, sex, race, and background immunosuppressive therapy use.²

READ MORE: First Report of MOG-IgG in Breast Milk After Severe MOGAD

The safety profile of satralizumab in METEOROID was consistent with more than 10 years of clinical trial and postmarketing experience with the drug in neuromyelitis optica spectrum disorder, spanning more than 10,000 treated patients. Adverse events (AEs) occurring in 5% or more of satralizumab-treated patients included injection-related reactions (16%), influenza (9%), arthralgia (9%), back pain (9%), sinusitis (7%), and diarrhea (6%), and treatment interruptions occurred in 6% of satralizumab-treated patients versus 5% of those receiving placebo.² One death occurred during the study and was assessed as unrelated to treatment, and no serious AEs were attributed to satralizumab.

“MOGAD can be unpredictable and debilitating, with each relapse carrying the potential for lasting neurological damage, yet there are currently no approved treatments,” Levi Garraway, MD, PhD, Roche's chief medical officer and head of global product development, said in a statement.¹ “Enspryng has the potential to transform care for people living with MOGAD, significantly reducing serious attacks and decreasing the reliance on high-dose steroids and immunosuppressants.”

“This would be the first proven therapy, scientifically proven, hopefully FDA approved, that would essentially prevent relapses in our MOGAD population,” Michael Levy, MD, PhD, associate professor at Harvard Medical School and Massachusetts General Hospital, said in a presentation of the METEOROID data.³

REFERENCES
1. U.S. FDA grants priority review for Roche's Enspryng for MOGAD, an autoimmune disease with no approved treatments. News release. Published September 10, 2026. Accessed September 10, 2026. https://www.globenewswire.com/news-release/2026/09/10/3359176/0/en/u-s-fda-grants-priority-review-for-roche-s-enspryng-for-mogad-an-autoimmune-disease-with-no-approved-treatments.html
2. Genentech's Enspryng (satralizumab) reduces risk of relapses by 68%, demonstrating potential to become first treatment for MOGAD. News release. Published April 21, 2026. Accessed September 10, 2026. https://www.gene.com/media/press-releases/15108/2026-04-21/genentechs-enspryng-satralizumab-reduces
3. Levy M, et al. Safety and efficacy of satralizumab in patients with relapsing myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD): results from the phase 3 METEOROID trial. Presented at: 2026 American Academy of Neurology Annual Meeting; April 18-22, 2026; Chicago, Illinois.
4. A study to evaluate satralizumab in participants with MOGAD (METEOROID). ClinicalTrials.gov identifier: NCT05271409. Accessed September 10, 2026. https://clinicaltrials.gov/study/NCT05271409