On December 17, 2021, global immunology company argenx SE (“argenx”) shared on its website that its therapy VYVGART (efgartigimod alfa-fcab) was approved by the FDA for the treatment of AChR-antibody positive adults with generalized myasthenia gravis (gMG). The approval, which hinged on data from a Phase 3 clinical trial, will now place a new and effective therapeutic option in the hands of those who need it.

VYVGART

To begin, let’s look at what VYVGART is. According to argenx, VYVGART is:

a first-in-class investigational [human IgG1] antibody fragment to target the neonatal Fc receptor (FcRn).

By targeting and binding to FcRn, VYVGART stops IgG antibodies from moving throughout the body. These antibodies can sometimes drive gMG progression and muscle weakness. As an estimated 85% of people with gMG are AChR-antibody-positive, this therapy has the potential to greatly improve quality of life (QOL).

As described above, the approval hinged on data from the Phase 3 ADAPT clinical trial. Altogether, 167 participants enrolled. Some findings, which were also published here, include:

• Overall, patients receiving VYVGART saw significantly higher overall response rates compared to a placebo. Patients saw significantly reductions on various scales which highlight gMG burden.
• VYVGART was relatively safe and well-tolerated. While some side effects did occur, these include headaches, rashes or hypersensitivity reactions, respiratory tract infections, and urinary tract infections.

Moving forward, argenx began My VYVGART Path to assist patients, families, and doctors throughout treatment. Through My VYVGART Path, argenx will offer various educational resources, financial assistance resources, and other options to maintain efficacy and accessibility for patients. This program also seeks to ensure that VYVGART is cost-friendly for patients. While the program is still in its earlier phases, you will be able to find more information on it here in the future.

Generalized Myasthenia Gravis (gMG)

Myasthenia gravis (MG) is aptly named, coming from the Greek and Latin for “grave muscle weakness.” This autoimmune neuromuscular disorder causes the body to mistakenly attack itself; in particular, autoantibodies attack the neuromuscular junction. As this occurs, the nerves and muscles cannot communicate properly, preventing normal muscle contraction. Although myasthenia gravis is treatable, a portion of patients are treatment-averse (meaning their conditions do not respond well to treatment). Ultimately, this causes them to develop generalized myasthenia gravis (gMG). Symptoms associated with gMG include:

• Severe fatigue
• Changes in vision, such as blurred or double vision
• Difficulty chewing and swallowing
• Slurred speech
• Eyelid drooping (on one or both sides)
• Shortness of breath and/or difficulty breathing
• Weakness of the upper and lower extremities
• Respiratory failure