Evaluation of the Acceptability and Therapeutic Maintenance After Substitution of Ustekinumab With a Biosimilar

This study is evaluating whether switching from Stelara® (ustekinumab) to a biosimilar version called Uzpruvo® is acceptable to patients with Crohn's disease who are in stable remission, and whether they continue to stay well after the switch. **You may be eligible if...** - You are 18 years or older - You have moderate-to-severe Crohn's disease being treated with Stelara® (ustekinumab) via pre-filled syringe every 8 or 12 weeks - You are in stable remission — meaning your dose has not changed in 24 weeks and you have been off steroids for at least 3 months - You and your doctor have already agreed to switch from Stelara® to Uzpruvo® - Your inflammatory markers (CRP, calprotectin) and symptom scores are within acceptable ranges **You may NOT be eligible if...** - You are under 18 years old - Your Crohn's disease is not in stable remission - You have not agreed to participate or allow use of your health data Talk to your doctor to see if this trial is right for you.