Comparison of outcomes parameters for induction of remission in new onset pediatric Crohn's disease: Evaluation of the porto IBD group "growth relapse and outcomes with therapy" (GROWTH CD) study

Background: Robust evaluation of induction therapies using both clinical and inflammatory outcomes in pediatric Crohn's disease (CD) are sparse. We attempted to evaluate clinical, inflammatory, and composite outcomes of induction of remission therapies (normal C reactive protein [CRP] remission) in a large pediatric prospective multicenter study. Methods: Patients enrolled at diagnosis into the growth relapse and outcomes with therapy in Crohn's disease study were evaluated for disease activity, CRP, and fecal calprotectin at 8, 12 and 52 weeks after starting treatment. The primary endpoint was week-12 steroid-free remission defined by pediatric Crohn's disease activity index and CRP <0.5 mg/dL. The protocol required tapering off corticosteroids by week 11. Results: We analyzed 222 patients (mean age, 12.9±3.2 yr) main evaluated treatment options included: 5-ASA (n = 29), exclusive enteral nutrition (n = 43), and corticosteroids (n = 114). Clinical remission at week 12 was achieved in 155 (73%) patients; both exclusive enteral nutrition and steroids were associated with normal CRP remission at week 12, although in a post hoc subgroup analysis exclusive enteral nutrition was superior in mild-tomoderate disease for this outcome. Among those in steroid-free remission in week 12, normal CRP predicted 1-year sustained remission (86% for normal CRP versus 61% for elevated CRP; P = 0.02). Baseline severity and early immunomodulation were similar in both groups. Conclusions: Normal CRP steroid-free remission at week 12 was impacted by type of induction therapy, but not by early immunomodulation. It was associated with more corticosteroids-free remission at week 52 and a trend for less relapses.