FDA Approves Argenx's Vyvgart To Treat Myasthenia Gravis

(RTTNews) - The U.S. Food and Drug Administration has granted approval for argenx BV's Vyvgart (efgartigimod) for the treatment of generalized myasthenia gravis or gMG in adults who test positive for the anti-acetylcholine receptor (AChR) antibody.

Myasthenia gravis is a chronic autoimmune, neuromuscular disease that causes weakness in the skeletal muscles, also called voluntary muscles, that worsens after periods of activity and improves after periods of rest.

The disease affects voluntary muscles, especially those that are responsible for controlling the eyes, face, mouth, throat, and limbs. In myasthenia gravis, the immune system produces AChR antibodies that interfere with communication between nerves and muscles, resulting in weakness. Severe attacks of weakness can cause breathing and swallowing problems that can be life-threatening.

The agency noted that Vyvgart is the first approval of a new class of medication for the rare, chronic, autoimmune, neuromuscular disease.

The approval was based on 26-week clinical study of 167 patients with myasthenia gravis to evaluate safety and efficacy of Vyvgart. The patients were randomized to receive either Vyvgart or placebo. The study showed that more patients with myasthenia gravis with antibodies responded to treatment during the first cycle of Vyvgart compared to those who received placebo.

The FDA granted this application Fast Track and Orphan Drug designations.

Billy Dunn, director of the Office of Neuroscience in the FDA's Center for Drug Evaluation and Research, said, "There are significant unmet medical needs for people living with myasthenia gravis, as with many other rare diseases. Today's approval is an important step in providing a novel therapy option for patients and underscores the agency's commitment to help make new treatment options available for people living with rare diseases."