This study is testing a medicine called amlitelimab in adults aged 18 to 75 with non-responsive celiac disease (NRCD). Celiac disease is a condition where eating gluten—a protein found in wheat, barley, and rye—causes damage to the intestines. Some people with celiac disease don't get better even on a gluten-free diet (GFD). The study will see if amlitelimab can help these patients by comparing it to a placebo, which is a "fake" medicine with no active ingredients.

Participants will be closely monitored and have multiple visits to the doctor over a period of either 48 weeks or up to 172 weeks if they choose to join an optional long-term study extension. The treatment phase lasts up to 28 weeks, during which the effect on gut health and symptoms will be recorded. This study will help understand how safe and effective amlitelimab is.

• Study duration: 48 weeks or up to 172 weeks with optional extension.
• 10 to 22 doctor visits required.
• Participants must follow a strict gluten-free diet and undergo specific medical tests.