argenx Preview on FDA's CIDP decision

CIDP could become the second marketed neuromuscular indication for efgartigimod in the US following gMG, pending expected FDA approval on June 21, 2024. In July 2023, argenx announced that it obtained positive topline data in its ADHERE study, featuring a 67% response rate in Stage A, and a primary endpoint hit in Stage B with a 61% reduction in risk of relapse versus placebo. We believe that efgartigimod could confer a treatment benefit over current treatment standards with sustained efficacy over a 48-week window, a clean safety profile and improved patient convenience. We anticipate that Vyvgart could obtain a broad label for CIDP, spanning all CIDP variants and both naïve and previously treated patients. Taking into account an addressable patient population of 36k patients across the US/EU-5 and a slight pricing premium over gMG, we anticipate CIDP peak sales could reach $ 3.05bn. CIDP represents 25% in our overall SOTP, while we reiterate our € 420 TP and Buy rating.