Argenx: FB102 achieves primary endpoint in Phase 2 celiac disease, moving toward Phase 3
Argenx obtained, on October 8, 2026, the first clinical readout of FB102 following the acquisition of Forte Biosciences in August 2026, and this Phase 2 study met its primary endpoint versus placebo. The group indicated that these data support advancing the candidate into Phase 3 in celiac disease, a condition for which no drug is currently approved.
For a group that already commercializes the first approved FcRn receptor blocker and achieved revenue of $4.25 billion for the 2025 fiscal year (accounts published March 24, 2026), this result represents the first clinical test of an asset acquired externally and based on a distinct mechanism, CD122 blockade. At the end of September, Argenx presented new data on Vyvgart, its marketed product, at the AANEM and MGFA congresses.
Significant improvement in intestinal mucosa at day 78
The FB102-301 study is randomized, double-blind, and placebo-controlled. It enrolled 126 adults with confirmed celiac disease without symptoms on a strict gluten-free diet for at least 12 months. Participants were allocated in a 2:2:1 ratio between two dose levels of FB102, administered by intravenous infusion, and placebo, while undergoing controlled oral gluten challenge for eight weeks.
The primary endpoint measured the change from baseline in the ratio of villous height to crypt depth in the intestinal mucosa at day 78. This indicator aims to determine whether the treatment protects the mucosa from damage caused by gluten. The difference versus placebo is statistically significant, with a p-value of 0.0176.
According to Argenx, other efficacy measures are consistent with this finding: density of intraepithelial lymphocytes, composite score combining histology and inflammation, as well as patient symptoms.
Safety profile consistent with prior data
From a safety perspective, the observed profile is consistent with previous studies and with the known profile of FB102, with no new signals identified. The group places these results in line with the Phase 1b trial, emphasizing that the protective effect was observed in the context of a more intense gluten challenge.
For Luc Truyen, Chief Medical Officer of Argenx, these data "reinforce our conviction" in the potential of FB102 and validate CD122 as a promising therapeutic target in celiac disease. The results communicated at this stage are preliminary results: detailed data will be presented at an upcoming medical congress.
This is also a Phase 2 trial involving 126 patients. In its forward-looking statement disclaimers, the group recalls that early-stage clinical trials may not be predictive of results from more advanced or larger-scale trials, and that interpretation of the data by regulatory authorities remains a step to be overcome.
Acceleration toward Phase 3 with FDA Fast Track designation
Argenx indicated that these results support the advancement of FB102 into Phase 3 in celiac disease. The U.S. Food and Drug Administration (FDA) has granted the candidate Fast Track designation in this indication. FB102 is also being evaluated in other autoimmune diseases, notably vitiligo and alopecia areata.
The medical need is based on data cited by the group: approximately 1% of the global population is affected by celiac disease, and studies report an increasing incidence of approximately 7.5% per year. Current management is limited to a strict gluten-free diet, while unintended gluten exposures from commonly consumed products are frequent.
The most structuring element of the announcement remains the achievement of the primary histological endpoint versus placebo, with a p-value of 0.0176 in 126 patients, which paves the way toward Phase 3 development as announced.
