Amgen has secured approval from the European Commission (EC) for Uplizna (inebilizumab) as an add-on treatment to standard therapy for adults with generalised myasthenia gravis (gMG) who are anti-acetylcholine receptor (AChR) or anti-muscle-specific tyrosine kinase (MuSK) antibody positive.
This approval provides a new option for long-term disease control in patients, with twice-yearly maintenance dosing after two initial loading doses. gMG is a rare, chronic, B-cell-mediated autoimmune condition resulting in fluctuating muscle weakness and affecting quality of life. The decision by the EC was supported by data from the Myasthenia Gravis Inebilizumab Trial (MINT).
MINT Trial Data
The MINT study is the largest Phase III biologic study to include both acetylcholine receptor-positive (AChR+) and muscle-specific tyrosine kinase-positive (MuSK+) patients, as well as the first to incorporate a structured steroid-tapering protocol.
Steroid Reduction Results: In the trial, patients receiving steroids at baseline began tapering at week four, aiming for prednisone 5mg per day by week 24. By week 26, 87.4% of patients on Uplizna and 84.6% on placebo reduced their steroid dose to 5mg or less per day.
MINT enrolled 238 adults with gMG, including 190 AChR+ and 48 MuSK+ patients. Criteria included Myasthenia Gravis Foundation of America (MGFA) classification of II–IV, myasthenia gravis activities of daily living (MG-ADL) score requirements, and stable steroid/immunosuppressive therapy at randomisation.
Uplizna previously received EC approval for active immunoglobulin G4-related disease in November 2025 and is also approved as a monotherapy for neuromyelitis optica spectrum disorder (NMOSD) in adults who are aquaporin-4 immunoglobulin G (AQP4-IgG) seropositive.
This regulatory milestone follows Amgen's September 2025 announcement of a significant $650m investment plan to enhance its manufacturing operations in the US.
