Amgen announced new data from the Phase 3, registrational MINT trial evaluating the efficacy and safety of UPLIZNA^® (inebilizumab-cdon) in adults living with generalized myasthenia gravis (gMG). The results demonstrated durable and sustained efficacy of UPLIZNA in patients with acetylcholine receptor autoantibody-positive (AChR+) gMG with two doses a year, following an initial loading dose. Findings will be presented as a late-breaking oral presentation during the American Academy of Neurology (AAN) Annual Meeting on April 8, 2025, in San Diego.

The Phase 3 MINT trial, which was a randomized-control trial, evaluated UPLIZNA in muscle-specific kinase autoantibody-positive (MuSK+) and AChR+ gMG patients, with the MuSK+ group followed for 26 weeks and the AChR+ group followed for 52 weeks. The trial demonstrated continued improvement in efficacy of UPLIZNA compared to placebo (adjusted difference, −2.8, 95% CI, −3.9 to −1.7) as measured by the change in baseline of Myasthenia Gravis Activities of Daily Living (MG-ADL) score in the AChR+ subpopulation through week 52. Among the AChR+ patients in the UPLIZNA group, 72.3% had a ≥3 point improvement in the MG-ADL score, compared to 45.2% in placebo.¹

As previously disclosed at the 2024 American Association of Neuromuscular & Electrodiagnostic Medicine Annual Meeting, the trial met its primary endpoint, with a statistically significant change from baseline in MG-ADL score for UPLIZNA (-4.2) compared with placebo (-2.2) (difference: –1.9, p<0.0001) at Week 26 for the combined study population.

"The 52-week MINT trial results highlight the potential for a new standard of care in gMG, offering durable symptom relief with a simplified treatment regimen," said Jay Bradner, M.D., executive vice president of Research and Development at Amgen. "These findings reinforce UPLIZNA's ability to provide sustained symptom relief with just two doses per year—an important advancement for patients living with generalized myasthenia gravis—while underscoring our commitment to developing transformative  therapies for people facing complex autoimmune diseases."

Change from baseline in the Quantitative Myasthenia Gravis (QMG) score was also greater for patients in the UPLIZNA group as compared to placebo at Week 52 (adjusted difference, −4.3, 95% CI, −5.9 to −2.8). Among the AChR+ patients in the UPLIZNA group, 69.2% improved by ≥3 points in the QMG score, compared to 41.8% in the placebo group.

MINT was the first and only Phase 3 trial for a biologic to incorporate a corticosteroid taper into its protocol. Patients who entered the study taking corticosteroids were tapered down starting at Week 4 to prednisone 5 mg per day by Week 24.

"I'm looking forward to further examining the 52-week MINT data with my colleagues in the neurology community at AAN," said Richard J. Nowak, M.D., M.S., global principal study investigator and director of the Myasthenia Gravis Clinic at Yale University. "These results showed that UPLIZNA consistently relieved burdensome symptoms and improved activities of daily living for gMG patients."

No new safety signals were identified. The overall TEAE profile during the study period is consistent with the known safety profile for the approved indication (NMOSD). The most common adverse events included infusion-related reactions, nasopharyngitis and urinary tract infections.

UPLIZNA is currently approved for the treatment of adult patients with anti-aquaporin-4 (AQP4) antibody positive neuromyelitis optica spectrum disorder (NMOSD) and is under priority FDA review for the treatment of Immunoglobulin G4-related disease (IgG4-RD) with a PDUFA date of April 3, 2025. The FDA has granted UPLIZNA Orphan Drug Designation for the treatment of gMG. Regulatory filing activities are underway with submission anticipated to be complete in H1 2025.