Ultrasound and Proteomics for Guselkumab Response Assessment in Crohn's Disease (UPGRADE).

This study uses intestinal ultrasound and blood protein analysis (proteomics) to monitor how well people with Crohn's disease respond to the biologic drug guselkumab (an IL-23 inhibitor). The goal is to find measurable markers that can tell doctors early whether the treatment is working without relying solely on colonoscopy. **You may be eligible if...** - You are 18 to 80 years old - You have Crohn's disease with active inflammation in the small intestine (ileum) visible on intestinal ultrasound - You have not previously received guselkumab - You may have either a non-stricturing or stricturing (narrowing) type of disease **You may NOT be eligible if...** - You have already received guselkumab - You are currently on medications that would interfere with the study drug or assessments - You have active infections or other conditions that preclude biologic therapy Talk to your doctor to see if this trial is right for you.