argenx Halts Phase 3 Sjogren's Disease Trial After Futility Review, Stock Drops 15%

argenx discontinued its Phase 3 UNITY study of subcutaneous efgartigimod in moderate-to-severe Sjogren's disease after an independent data monitoring committee determined the trial could not meet its primary endpoint, the Week 48 clinESSDAI score, at an interim futility review. No new safety signals were identified. The company said the decision was based solely on the trial's inability to demonstrate efficacy at the prespecified threshold.

The news sent argenx shares down roughly 13 to 15.6 percent in premarket trading on October 8, making it one of the largest premarket decliners of the session. The Sjogren's indication had been a closely watched expansion target for efgartigimod, which is already approved in myasthenia gravis.

Separately, argenx reported favorable Phase 2 results for FB102 in celiac disease, an asset acquired through its purchase of Forte Biosciences, and said it plans to advance that program into Phase 3 development. The positive celiac data offered a partial offset to the Sjogren's setback but was insufficient to halt the broad selloff in the stock.