FDA Accepts Filing for Efgartigimod for the Treatment of Generalized Myasthenia Gravis 

The Food and Drug Administration (FDA) has accepted a Biologics License Application for intravenous (IV) efgartigimod (ARGX-113; Argenx, Breda, Netherland) for treatment of generalized myasthenia gravis (gMG). The FDA has set a 10-month review process with a Prescription Drug User Fee Act (PDUFA) target action date of December 17, 2021. 

The BLA is supported by results from the pivotal phase 3 ADAPT trial (NCT03669588), in which 67% of individuals with gMG who were positive for antibodies to the acetylcholine receptor (antiAChR+) responded to efgartigimod treatment as measured by the Myasthenia Gravis Activities of Daily Living (MG-ADL) scale. In comparison, 30% of participants treated with placebo had improvements on the MG-ADL (P<.0001). Minimal symptom expression, defined as a score of 0 on MG-ADL, was achieved by 40% of participants treated with efgartigimod vs 11% of those treated with placebo. For the open-label extension trial of efgartigimod, 90% of participants opted to continue or start treatment with efgartigimod. 
 
“This is an important milestone for Argenx in our transition to a commercial-stage company and brings us closer to our mission to reach patients living with gMG, a debilitating neuromuscular disease,” said Tim Van Hauwermeiren, chief executive officer of Argenx. “We look forward to closely collaborating with the FDA through the BLA review process and to potentially making our first medicine available.”

Argenx has a preapproval access (PAA) program in the US, which will allow eligible people living with gMG to receive treatment with efgartigimod.