Vyvgart

Vyvgart Overview:

Vyvgart (efgartigimod alfa-fcab) is a first-in-class biologic for adults with generalized myasthenia gravis (gMG), a chronic autoimmune disease that causes muscle weakness and fatigue. Vyvgart was first FDA approved on December 17, 2021, and is made by argenx. In May 2026, the FDA expanded the indication to cover adult gMG of every antibody type, including anti-MuSK, anti-LRP4, and triple-seronegative patients. Before that, it was limited to AChR antibody-positive patients.

Understanding Vyvgart:

In myasthenia gravis, IgG autoantibodies attack the junction where nerves signal muscles, which causes weakness in the eyes, face, throat, limbs, and breathing muscles. Vyvgart is a neonatal Fc receptor (FcRn) blocker. FcRn normally recycles IgG antibodies and keeps them circulating. When Vyvgart blocks FcRn, IgG, including the harmful autoantibodies, breaks down faster and IgG levels drop. This can improve symptoms such as drooping eyelids, double vision, difficulty swallowing or speaking, limb weakness, and shortness of breath. Vyvgart does not suppress the whole immune system.

Unlocking Vyvgart’s Potential:

Vyvgart is given as an intravenous infusion in treatment cycles. Approval was based on the Phase 3 ADAPT trial, in which significantly more anti-AChR antibody–positive patients responded on the MG-ADL (Activities of Daily Living) scale. For seronegative patients, the Phase 3 ADAPT SERON trial showed a 3.35-point MG-ADL improvement, with benefit in the MuSK, LRP4, and triple-negative subgroups. A subcutaneous form, Vyvgart Hytrulo (efgartigimod alfa and hyaluronidase-qvfc), is also available. Vyvgart Hytrulo is also approved for adults with chronic inflammatory demyelinating polyneuropathy (CIDP).

Navigating Dosage and Administration:

• Dose: 10 mg/kg, infused IV over about one hour, once weekly for 4 weeks. This makes up one treatment cycle.
• Weight cap: Patients weighing 120 kg or more receive a maximum of 1,200 mg per infusion.
• Later cycles: Further cycles are scheduled based on the patient’s clinical evaluation. The safety of starting a new cycle sooner than 50 days after the start of the previous one has not been established.
• Monitoring: Patients are watched during and after each infusion for hypersensitivity or infusion-related reactions.

Preparing for Vyvgart Treatment:

Before starting treatment, the care team reviews:

• The patient’s diagnosis and medical history
• Any current infections
• Vaccination status
• Current medications
• Pregnancy or breastfeeding plans

Vaccinations should be brought up to date before treatment starts. Live or live-attenuated vaccines are not recommended during treatment. Vyvgart can lower the levels, and possibly the effectiveness, of other drugs that depend on FcRn, such as IV immunoglobulin (IVIG) and some monoclonal antibodies, so the care team considers timing with these products.

Vyvgart Side Effects:

Vyvgart is generally well tolerated. The most common side effects include:

• Respiratory tract infections
• Headache
• Urinary tract infections
• Tingling or prickling sensations (paresthesia)
• Muscle pain (myalgia)

Serious but less common risks include:

• Infections: Because Vyvgart lowers IgG levels, it may increase infection risk. Starting treatment is delayed if a patient has an active infection.
• Hypersensitivity reactions: These can include rash, angioedema, shortness of breath, and in rare cases anaphylaxis.
• Infusion-related reactions: These can include high blood pressure, chills, shivering, and chest, abdominal, or back pain.

Patients with a history of serious hypersensitivity to efgartigimod or any of its ingredients should not receive Vyvgart. Healthcare providers monitor patients closely and act promptly if any reaction occurs.

Empowering Myasthenia Gravis Management with Vyvgart:

Vyvgart is a targeted way to manage generalized myasthenia gravis. It lowers the disease-causing autoantibodies directly rather than broadly suppressing the immune system. Its cycle-based infusion schedule can be adjusted to each patient’s needs, and it is now approved for adults regardless of antibody status. For many people living with gMG, it offers a path to better muscle strength, daily function, and quality of life.