Remission maintained by monotherapy after biological plus immunosuppressive combination for Crohn's disease in clinical practice

Background and Aim: The optimal time towithdraw combined biological + immunosuppressive therapy in Crohn's disease is debated. Following remission of 6months with the combined therapy, we assessed the efficacy of monotherapy in maintaining remission. Methods: Crohn's disease patients (n = 75) were retrospectively selected from clinical records for having achieved remission within 6months of receiving combined biological + immunosuppressive therapy. Treatment continued for a further year with one or the other of the combination drugs withdrawn. Clinical remission was defined as Crohn's Disease Activity Index (CDAI) < 150 and endoscopic remission as CDAI< 150 + absence of mucosal lesions + no signs of active inflammation on ileocolonoscopy. Crohn's disease relapse was defined as CDAI > 250. Results: Twenty-eight percent (21/75) patients were relapsers. Withdrawal of biological therapy was more frequent than immunosuppressive (73.3% vs 26.7%) with no significant differences in relapse rates (30.9% vs 20%; P = 0.401). Endoscopic remission was more accurate than clinical remission (relapse rates: 10.5% vs 33.9%; P = 0.05). C-reactive-protein was higher in relapsers (19.2 +/- 23.7mg/L vs 2.5 +/- 4.7mg/L; P = 0.009). Multivariate analysis indicated C-reactive protein > 5mg/L (odds ratios [OR]: 30.12; 95% confidence intervals [95% CI]: 5.91-153.38; P = 0.0001) and younger age at diagnosis (OR: 1.10; 95% CI: 1.01-1.19; P = 0.047) as independent factors predicting relapse. There was a strong trend toward a protective effect of endoscopic remission (OR: 0.17; 95% CI: 0.02-1.22; P = 0.077). Conclusion: A subgroup of Crohn's disease patients treated with combination therapy can be identified (C-reactive protein < 5mg/L, endoscopic remission, and older age at Crohn's disease diagnosis) who would continue in remission despite cessation of the biological (expensive) component of the combination therapy.