Amgen’s Uplizna wins European Commission approval for generalized myasthenia gravis | iPharmaCenter

Amgen has secured European Commission clearance for Uplizna (inebilizumab) as an add‑on therapy for adults with generalized myasthenia gravis (gMG) who test positive for anti‑acetylcholine receptor (AChR) or anti‑muscle‑specific tyrosine kinase (MuSK) antibodies.

The decision introduces a targeted B‑cell–depleting option that can be given as two loading infusions followed by maintenance dosing twice a year, with the aim of providing sustained disease control alongside existing standard treatments.

Generalized myasthenia gravis is a rare, chronic, B‑cell–mediated autoimmune disorder characterised by fluctuating skeletal‑muscle weakness that can impair daily activities and quality of life; across Europe, myasthenia gravis as a whole is thought to affect tens of thousands of people, a subset of whom have the generalized form.

The EC decision rests on results from the phase 3 Myasthenia Gravis Inebilizumab Trial (MINT), the largest biologic study in gMG to enrol both AChR‑positive and MuSK‑positive patients and the first in this setting to prospectively embed a structured steroid‑tapering protocol.

In MINT, 238 adults with gMG (190 AChR‑positive and 48 MuSK‑positive) were randomly assigned to inebilizumab or placebo on top of stable background immunosuppression, with entry criteria requiring MGFA class II–IV disease, defined thresholds on MG‑ADL and QMG scores, and stable use of corticosteroids and/or other immunosuppressants.

Steroid‑treated participants began a protocol‑guided taper from week 4, targeting a daily prednisone dose of 5 mg by week 24, and by week 26 more than four out of five patients in both arms had reduced to 5 mg or less, underscoring the feasibility of steroid minimisation within this regimen.

The primary outcome, change from baseline in MG‑ADL at week 26 in the overall study population, favoured Uplizna with a 1.9‑point greater improvement versus placebo (–4.2 versus –2.2), a difference regarded as clinically meaningful on the 0–24 scale that captures the impact of gMG on eight key daily‑function domains.

Key secondary endpoints showed a 2.5‑point advantage on the QMG score for the combined population at week 26 (–4.8 with inebilizumab versus –2.3 with placebo), and consistent benefits in MG‑ADL and QMG in the AChR‑positive subgroup, while MuSK‑positive patients experienced significant MG‑ADL improvements and numerically better, though not statistically significant, QMG changes. Longer‑term exploratory analyses indicated that AChR‑positive patients maintained and deepened responses through week 52, with larger MG‑ADL and QMG improvements versus placebo at one year.

The new indication extends Uplizna’s European footprint beyond neuromyelitis optica spectrum disorder (NMOSD) in AQP4‑IgG–positive adults and active immunoglobulin G4‑related disease (IgG4‑RD), where the medicine is already authorised as a B‑cell–depleting therapy targeting CD19‑expressing cells. With the addition of gMG, Uplizna now spans three rare, antibody‑mediated conditions in Europe, positioning the drug as an important option for patients who require durable immunomodulation with infrequent intravenous dosing