Argenx’s Vyvgart Hytrulo (subcutaneous efgartigimod alfa) cleared a major Phase 3 milestone in immune-mediated necrotizing myopathy, with the drug meeting statistical significance in a key subgroup where no approved targeted therapies exist. The result follows Argenx’s push to translate its FcRn blockade franchise from intravenous use into self-administered formulations. Argenx said patients receiving Hytrulo showed rapid and sustained improvements, with efficacy driven particularly in the IMNM subset. The company also indicated Total Improvement Score gains with a steroid-tapering framework during treatment. The dataset is likely to shape the company’s next regulatory steps, with investors focused on whether the myositis label can expand meaningfully beyond dermatomyositis and into IMNM where unmet need is highest.