Written By: Pharmacally Medical News Desk
The U.S. Food and Drug Administration has expanded the indication of Uplizna (inebilizumab-cdon) to include adults with generalized myasthenia gravis who are positive for anti-AChR or anti-MuSK antibodies. The decision is based on the phase 3 MINT trial, which showed clinically meaningful improvements in MG symptoms, activities of daily living, and muscle strength compared with placebo on top of standard of care.
Uplizna is marketed by Amgen and was previously approved for neuromyelitis optica spectrum disorder (NMOSD) in adults with anti-AQP4 antibodies, making gMG its second major autoimmune neurology indication. With this approval, Uplizna becomes a novel option for patients who often experience fluctuating weakness affecting eye movements, bulbar function, respiration, and limb strength despite existing therapies.
Jay Bradner, M.D., Executive Vice President, Research and Development, Amgen, said the approval highlights UPLIZNA’s potential to address the biological root cause of generalized myasthenia gravis while offering durable efficacy with a convenient twice-yearly dosing schedule.
Understanding Generalized Myasthenia Gravis
Generalized myasthenia gravis is a rare, long-term autoimmune condition in which pathogenic antibodies disrupt neuromuscular transmission. Patients typically experience:
- Muscle weakness affecting the eyes, face, limbs, and respiratory muscles
- Fatigability that worsens with activity
- Fluctuating symptoms that can significantly impair daily functioning
Most cases are driven by autoantibodies against acetylcholine receptors (AChR), while others involve MuSK or related targets. Despite available therapies, many patients continue to have residual symptoms or require long-term immunosuppression.
UPLIZNA
UPLIZNA works by depleting CD19-positive B cells, a population that includes precursor and mature B cells responsible for producing pathogenic antibodies. By targeting CD19 rather than CD20, UPLIZNA affects a broader spectrum of antibody-producing cells, potentially leading to deeper and more sustained immune modulation.
This mechanism is designed to reduce autoantibody levels over time, addressing an upstream driver of disease activity rather than only managing symptoms.
Clinical Evidence Supporting Approval
The FDA approval was based on data from the Myasthenia Gravis Inebilizumab Trial (MINT), a pivotal Phase 3 clinical trial evaluating UPLIZNA in adults with generalized myasthenia gravis. Key findings included:
- Significant improvement in MG-ADL scores compared with placebo at 26 weeks, with benefits sustained through longer follow-up Sustained symptom control across multiple muscle groups
- Reduced disease activity with a durable response over the treatment period
- Consistent benefit across clinically relevant patient subgroups
These outcomes demonstrated that UPLIZNA meaningfully improved daily functioning and disease burden in patients with gMG.
Dosing and Administration
UPLIZNA is administered as an intravenous infusion, with:
- Two initial loading doses
- Followed by maintenance dosing every six months
This infrequent dosing schedule may reduce treatment fatigue and improve adherence compared with therapies requiring more frequent administration.
Safety Profile
The safety profile of UPLIZNA in gMG was generally consistent with its known use in other autoimmune indications. Commonly reported adverse events included:
- Infusion-related reactions
- Upper respiratory tract infections
- Headache and nasopharyngitis
Serious infections were infrequent, but as with other B-cell-depleting therapies, appropriate patient screening and monitoring are recommended.
The approval of UPLIZNA for generalized myasthenia gravis is significant because it:
- Expands access to targeted B-cell therapy in gMG
- Offers a low-frequency dosing option, addressing long-standing treatment burden
- Reinforces the role of precision immunotherapy in antibody-driven neuromuscular diseases
For patients with persistent symptoms despite standard care, UPLIZNA provides a new option focused on long-term disease control.
Richard J. Nowak, M.D., M.S., Global Principal Investigator of the MINT study and Director of the Myasthenia Gravis Clinic at Yale University, said UPLIZNA demonstrated strong efficacy in both AChR-positive and MuSK-positive patients, with sustained improvement and reduced dependence on long-term steroid therapy.
Samantha Masterson, President and Chief Executive Officer of the Myasthenia Gravis Foundation of America, said the approval represents a meaningful milestone by reducing treatment burden and allowing patients extended treatment-free periods between maintenance doses.
References
FDA approves uplizna® for adults with generalized myasthenia gravis, 11 December 2025, Amgen, https://investors.amgen.com/news-releases/news-release-details/fda-approves-upliznar-adults-generalized-myasthenia-gravis
Myasthenia Gravis Inebilizumab Trial (MINT), ClinicalTrials.gov ID NCT04524273, https://clinicaltrials.gov/study/NCT04524273