LAUSR

BACKGROUND AND AIMS The therapeutic efficacy and safety of ustekinumab for Crohn's disease (CD) have been reported from randomized controlled trials and real-world data. However, there are few studies describing the identification of patients most suitable for ustekinumab therapy. The aim of this study was to prospectively evaluate the patients receiving ustekinumab and identify predictors of the treatment efficacy. METHODS Patients with moderate to severe active CD scheduled to receive ustekinumab were enrolled. The responders and nonresponders were compared at weeks 0, 8, 24, and 48 by evaluating patient demographics, simple endoscopic scores (SES-CD), ustekinumab and cytokine concentrations, and cellular fractions. RESULTS The clinical response and clinical remission rates in the 22 enrolled patients were 59.1% and 31. 8% at week 8, 68.2% and 45.5% at week 24, and 54.4% and 40.9% at week 48, respectively. There were no significant differences in patients' demographic and disease characteristics at baseline between responders and nonresponders. A combination of low SES-CD and high serum TNF-α concentration at baseline showed a good correlation with the clinical response. Serum TNF-α concentration was decreased because of the therapy. The ratio of CD4+TNF-α cells at baseline was significantly higher in responders than in nonresponders; however, the ratios of CD45+CD11b+TNF-α and CD45+CD11c+TNF-α cells were not different. The ratio of CD4+ TNF-α cells decreased with the treatment in the responders but not in the nonresponders. CONCLUSIONS The combination of 2 factors, namely higher serum TNF-α concentration and lower SES-CD at baseline, may assist clinicians in selecting the appropriate therapy for patients with moderate to severe CD.