Argenx suffered a major clinical setback on October 8, 2026, when it discontinued a Phase 3 trial of its blockbuster drug Vyvgart in Sjögren's disease because the treatment failed to outperform a placebo. The announcement sent Argenx shares tumbling up to 18%, wiping out approximately $9.5 billion in market value and overshadowing the company's concurrent decision to advance a newly acquired celiac disease drug into late-stage development.
Discontinuation of Sjögren's disease trial
- ▪Argenx discontinued a Phase 3 clinical trial of its drug efgartigimod, commercialized as Vyvgart, in adults with Sjögren's disease on October 8, 2026
- ▪An independent data monitoring committee recommended stopping the Sjögren's disease study after an interim analysis concluded it was unlikely to meet its primary endpoint
- ▪Argenx's drug Vyvgart failed to outperform a placebo in the clinical trial of patients with Sjögren's disease, a chronic autoimmune disorder that damages tear and saliva glands
Stock market reaction
- ▪On October 8, 2026, Argenx shares fell between 13% and 18%, erasing approximately €8.5 billion ($9.5 billion) from its market value, wiping out year-to-date gains, on track for its largest one-day decline since December 2023
- ▪On October 8, 2026, Argenx shares became the biggest decliner on Europe's healthcare index, which fell 1.8% overall
Story comments
Loading comments…