argenx SE (Euronext & Nasdaq: ARGX) reported on August 17 that its Phase 3 ALKIVIA trial of subcutaneous efgartigimod (marketed as VYVGART Hytrulo) achieved its primary goal in adults with autoimmune myositis, a chronic inflammatory muscle disease with few treatment options.
Across the combined cohort of immune-mediated necrotizing myopathy (IMNM) and dermatomyositis (DM) patients, those receiving efgartigimod posted a 15.4-point edge over placebo on the Total Improvement Score at one year (47.95 versus 32.56; p=0.0011). Benefits appeared as early as week four and held through a full year of dosing, even as background steroids were tapered.
Notably, IMNM patients, a group with no approved targeted therapy, showed a statistically significant 14.8-point gain over placebo. DM patients improved by a comparable 14.5 points, though this subgroup narrowly missed statistical significance given its smaller size. Investigators noted gains spanned muscle strength, physical function, and, in DM, skin involvement, with a tolerability profile consistent with efgartigimod’s established record.
“These results confirm that pathogenic IgG antibodies drive this disease, and blocking FcRn can meaningfully change outcomes for patients who have long relied only on steroids,” said Dr. Luc Truyen, argenx’s Chief Medical Officer.
The company plans to present full data at a forthcoming scientific congress and will discuss the readout on an investor call later today. argenx is also studying efgartigimod in Sjogren’s disease and systemic sclerosis. Zai Lab, argenx’s partner for Greater China, contributed patients to the global trial through its regional license for VYVGART Hytrulo.
Written By: Sayan Das
Graphics by: Pramit Hazra
