US Stock Market Move | Argenx (ARGX.US) pre-market rose over 10% as its autoimmune myositis drug Vyvgart reached its primary endpoint in Phase III trials.

On Monday before the U.S. stock market opened, shares of European biotechnology company Argenx (ARGX.US) surged 10.38%. The company announced on Monday that its autoimmune myositis drug Vyvgart met its primary endpoint in a Phase III study. Argenx stated that, compared to the placebo group, patients receiving the drug displayed statistically significant improvements in their average total improvement score by week 52. Autoimmune myositis is a disease in which the immune system attacks muscles, potentially swiftly depriving patients of their ability to care for themselves. Argenx is expanding the indications for its core drug Vyvgart, aiming to cover a broader patient population and solidify its leading position in the field of autoimmune diseases. Analyst Michael Shah noted that these results could serve as a basis for Vyvgart's approval in the U.S. Patients with such diseases have long relied mainly on steroids and other broad-spectrum immunosuppressants. Rohit Aggarwal, a professor at the University of Pittsburgh School of Medicine and one of the leads on the study, stated that this result represents a significant advancement in helping patients move away from steroids, which have serious side effects. However, the trial results are not entirely consistent, as Vyvgart did not show statistically significant efficacy in another cohort of patients with concurrent skin symptoms. Shah indicated that it remains unclear how regulators will interpret this outcome.