This study tests a drug called **amlitelimab** on adults with celiac disease who don't get better on a gluten-free diet. Celiac disease is when the body can't handle gluten, a protein in wheat and other grains. Amlitelimab is given through a shot under the skin, and the study wants to see if it helps the gut heal and reduces symptoms like stomach pain or bloating.

Participants will be randomly given either amlitelimab or a placebo (a fake treatment) without knowing which one they receive. The main goal is to check if amlitelimab works better than the placebo by looking at gut health and symptoms. Safety and how the body handles the drug will also be studied.

• The study lasts up to 48 weeks with 10 visits, or up to 172 weeks with 22 visits if you join the optional long-term part.
• Participants must be 18-75 years old and willing to follow their current gluten-free diet during the study.
• Participants will have 2 endoscopies to check their gut health.

Not everyone can join. People with other serious gut problems or certain health conditions can't participate.