Early fecal calprotectin levels at week 8 may guide therapeutic decisions on Ustekinumab therapy in patients with Crohn's disease.

Continuation of UST therapy without endoscopic response evaluation may be considered in patients with a decrease in FC levels of ≥500 µg/g at week 8. The decision on continuation of UST therapy or therapy optimization needs reconsideration in patients without a decrease of FC level. In all other patients, endoscopic response evaluation of induction therapy remains essential for therapeutic decisions.