N Engl J Med

AAN 2025: Inebilizumab shows promise in treating generalized myasthenia gravis

April 11, 2025

Inebilizumab offers a promising new treatment option for patients with generalized myasthenia gravis (gMG), particularly those with anti-acetylcholine receptor (AChR) or anti-muscle-specific kinase (MuSK) antibodies, by significantly improving functional outcomes and reducing disease severity. These findings were presented as a late-breaking oral presentation during the American Academy of Neurology (AAN) Annual Meeting.

Study details: The phase 3 randomized, placebo-controlled Myasthenia Gravis Inebilizumab Trial (MINT) evaluated the efficacy and safety of inebilizumab in 238 patients with gMG who had AChR or MuSK antibodies. Participants were randomized 1:1 to receive IV inebilizumab (300 mg on days 1 and 15, and on day 183 for AChR antibody-positive patients) or placebo over 26 or 52 weeks, depending on antibody status. Glucocorticoid therapy was tapered to a target of 5 mg/day by week 24.

Results: Inebilizumab significantly reduced the Myasthenia Gravis Activities of Daily Living (MG-ADL) score compared with placebo (adjusted difference, -1.9; 95% confidence interval [CI], -2.9 to -1.0; P<0.001) at week 26. Similarly, the Quantitative Myasthenia Gravis (QMG) score showed greater reduction with inebilizumab. Among the AChR+ patients in the inebilizumab group, 69.2% improved by ≥3 points in the QMG score, compared with 41.8% in the placebo group (adjusted difference, -2.5; 95% CI, -3.8 to -1.2; P<0.001). Common adverse events included headache, cough, nasopharyngitis, infusion-related reactions, and urinary tract infections, with no increase in serious adverse events.

Sources:

Nowak RJ, et al; MINT Investigators. (2025, April 8). N Engl J Med. A Phase 3 Trial of Inebilizumab in Generalized Myasthenia Gravis. https://pubmed.ncbi.nlm.nih.gov/40202593/

(2025, March 13). Amgen. Uplizna (inebilizumab-cdon) significantly improves generalized myasthenia gravis symptoms in acetylcholine receptor autoantibody-positive patients over 52 weeks. [Press release]. https://www.amgen.com/newsroom/press-releases/2025/03/uplizna-inebilizumabcdon-significantly-improves-generalized-myasthenia-gravis-symptoms-in-acetylcholine-receptor-autoantibodypositive-patients-over-52-weeks