argenx reports Phase 2 FB102 celiac trial met primary endpoint

A biopsy-based endpoint was met in a Phase 2 celiac study on Thursday as argenx SE EBRARGX NASDAQARGX said its FB102 antibody beat placebo following a gluten challenge. The Oct. 8 topline announcement reported a p value of 0.0176 and a plan to advance the drug into Phase 3 development.

The trial measured the change from baseline in the ratio of villus height to crypt depth at day 78, a biopsy measure of intestinal damage. Argenx said the improvement over placebo was statistically significant, but it has not given a date for the planned Phase 3 study in the topline text reviewed.

The Amsterdam-based immunology company sells VYVGART for autoimmune diseases and develops other antibody medicines across its pipeline.

The NASDAQARGX quote page showed argenx's depositary shares closed Wednesday at US$928.44 as of 4:00:01 p.m. EDT. That close preceded Thursday's announcement, so it does not measure a market reaction to the celiac result.

Argenx Plans Phase 3 Development

The trial enrolled adults with celiac disease undergoing a gluten challenge and compared FB102 with placebo. A smaller loss of villus height relative to crypt depth would indicate less intestinal injury, but the p value alone does not give the size of the difference between the treatment arms.

The portion of the topline statement available for this report did not establish the number of evaluable patients or the arm-level changes. Argenx said measures of inflammatory cell density, a composite biopsy score and symptoms were consistent with the primary endpoint, without providing numerical results for those measures in the text reviewed.

The company said the observed safety profile matched prior FB102 studies and identified no new safety signals. It plans to share detailed results at a future medical meeting, although the statement did not give a presentation date.

"Combined with the consistent safety profile observed across studies, these findings support advancing FB102 into Phase 3 development and further exploring its broader potential across immune-mediated diseases," argenx chief medical officer Luc Truyen said in the release.

The result is the first FB102 clinical readout since argenx completed its acquisition of Forte Biosciences on Aug. 27. Forte had reported an earlier positive celiac signal in June 2025, and argenx acquired the anti-CD122 antibody along with programs in other immune diseases.

Argenx reported US$1.5 billion in second-quarter product sales and US$472 million in quarterly profit in its July 23 results. Its topline celiac announcement did not set out the cost, enrollment or FDA feedback for a Phase 3 study, leaving the design of that next test to be disclosed.

Teva Reported a Separate Celiac Signal

Teva Pharmaceutical Industries Ltd. NYSETEVA reported a Phase 2a celiac result on Sept. 2 for TEV '408, an antibody that blocks IL-15. Its study enrolled 50 adults. The least squares mean changes in the same biopsy ratio were minus 0.43 with TEV '408 and minus 0.88 with placebo at week eight.

Teva reported a treatment difference of 0.45, with a 95 per cent confidence interval of 0.06 to 0.84. Those figures come from a separate trial and do not establish which drug performs better; the FB102 topline text reviewed did not give corresponding arm-level figures.

Argenx's July 23 update forecast a fourth-quarter 2026 readout from the separate registrational EMPASSION study in multifocal motor neuropathy. That result will show whether empasiprubart met the study's endpoint.