The US Food and Drug Administration (FDA) has approved the first treatments for all serotypes of patients living with generalised myasthenia gravis (gMG). 

The FDA’s label expansion of Vyvgart (efgartigimod alfa-fcab) and Vyvgart Hytrulo (efgartigimod alfa and hyaluronidase-qvfc) now means gMG adult patients can treat all serotypes, including anti-AChR-Ab positive, anti-MuSK-Ab positive, anti-LRP4-Ab positive, and triple seronegative. 

The approval is based on data from the Phase III study of patients with gMG, who did not have detectable anti-acetylcholine receptor antibodies (AChR-Ab), across three serotypes. These serotypes included anti-MuSK-Ab positive, anti-LRP4-Ab positive, and triple seronegative.  

The overall population showed rapid, significant and sustained improvements in their gMG symptoms, including speech, vision, physical function and swallowing, among others. Vyvgart was also well tolerated across serotypes, with safety consistent with the established profile in patients with anti-AChR Ab positive gMG. 

“[This] approval means that all adult gMG patients, regardless of serotype, can now benefit from Vyvgart’s rapid onset, sustained disease control, and favourable safety profile,” said Luc Truyen, Chief Medical Officer at argenx, the immunology company that developed the treatments. 

“For clinicians, this simplifies treatment decisions, representing a major advancement in reaching as many patients living with gMG as possible.” 

“For too long, gMG patients who do not have detectable AChR-Ab have been left behind, feeling disengaged and excluded from receiving treatments that specifically treat their disease, which has led to patients experiencing a higher burden of suffering,” added Allison Foss, Executive Director of the Myasthenia Gravis Association.  

“This approval validates that gMG patients without AChR-Ab can benefit from a targeted treatment, bringing a sense of hope to thousands in our community.”