argenx: Phase 2 shows FB102 protects intestine in celiac disease

Topline results

FB102, a first‑in‑class CD122 inhibitor, produced a statistically significant and clinically relevant treatment effect versus placebo in adults with celiac disease undergoing a controlled gluten challenge. The study met its primary endpoint of change from baseline in the villus height–to–crypt depth (Vh:Cd) ratio at day 78 versus placebo (p=0.0176). Secondary measures— intraepithelial lymphocyte (IEL) density, the VCIEL composite score, and symptom assessments—were consistent with the primary endpoint.

Study design

FB102‑301 (NCT06982963) was a randomized, double‑blind, placebo‑controlled Phase 2 trial that enrolled 126 patients with confirmed celiac disease who were symptom free on a strict gluten‑free diet for at least 12 months. Participants were randomized 2:2:1 to receive intravenous infusions of two FB102 dose levels or placebo while undergoing a controlled eight‑week oral gluten challenge to assess protection from gluten‑induced intestinal damage.

Safety and next steps

The observed safety profile was consistent with prior studies and the known profile of FB102, with no new safety signals identified. These topline data follow argenx’s August 2026 acquisition of Forte Biosciences and support plans to advance FB102 into Phase 3 development; FB102 is also being evaluated in vitiligo and alopecia areata, and has received FDA Fast Track designation for celiac disease.