Retreatment with anti-tumor necrosis factor therapy in combination with an immunomodulator for recurrence of Crohn's disease after ileocecal resection results in prolonged continuation as compared to anti-tumor necrosis factor monotherapy

Background: A considerable proportion of Crohn's disease patients that undergo ileocecal resection (ICR) have failed anti-tumor necrosis factor (TNF) therapy preoperatively. This study aimed to assess the effectiveness of retreatment of anti-TNF therapy in patients with postoperative recurrence. Methods: A real-world cohort study was performed on Crohn's disease patients who underwent primary ICR after anti-TNF therapy failure, and who were retreated with anti-TNF therapy for postoperative symptomatic Crohn's disease. The primary outcome was treatment failure (the need for (re)introduction of corticosteroids, immunosuppressants, or biologicals or the need for re-resection). Sub-analyses were performed on the nature of preoperative anti-TNF failure (primary non-response, secondary loss of response, intolerance), indication for ICR (refractory, stricturing, penetrating disease), combination therapy with immunomodulators, retreatment with the same anti-TNF agent and preoperative exposure to 1 vs. >1 anti-TNF agents. Results: In total, 66 of 364 patients retreated with anti-TNF therapy following ICR. Cumulative rates of treatment failure at 1 and 2 years were 28% and 47%. Treatment failure rate at 2 years was significantly lower in patients receiving combination therapy as compared to anti-TNF monotherapy (30% vs. 49%, P = 0.02). No difference in treatment failure was found with regards to the nature of preoperative anti-TNF failure (P = 0.76), indication for ICR (P = 0.88) switch of anti-TNF agent (P = 0.55) agent, and preoperative exposure to 1 vs. >1 anti-TNF agents (P = 0.88). Conclusion: Retreatment with anti-TNF therapy for postoperative Crohn's disease recurrence is a valid strategy after preoperative failure. Combination therapy is associated with a lower rate of treatment failure.</p

Validation and update of a prediction model for risk of relapse after cessation of anti-TNF treatment in Crohn's disease

Background Anti-tumor necrosis factor (TNF) therapy is effective for the treatment of Crohn's disease. Cessation may be considered in patients with a low risk of relapse. We aimed to externally validate and update our previously developed prediction model to estimate the risk of relapse after cessation of anti-TNF therapy. Methods We performed a retrospective cohort study in 17 Dutch hospitals. Crohn's disease patients in clinical, biochemical or endoscopic remission were included after anti-TNF cessation. Primary outcome was a relapse necessitating treatment. Discrimination and calibration of the previously developed model were assessed. After external validation, the model was updated. The performance of the updated prediction model was assessed in internal-external validation and by using decision curve analysis. Results 486 patients were included with a median follow-up of 1.7 years. Relapse rates were 35 and 54% after 1 and 2 years. At external validation, the discriminative ability of the prediction model was equal to that found at the development of the model [c-statistic 0.58 (95% confidence interval (CI) 0.54-0.62)], though the model was not well-calibrated on our cohort [calibration slope: 0.52 (0.28-0.76)]. After an update, a c-statistic of 0.60 (0.58-0.63) and calibration slope of 0.89 (0.69-1.09) were reported in internal-external validation. Conclusion Our previously developed and updated prediction model for the risk of relapse after cessation of anti-TNF in Crohn's disease shows reasonable performance. The use of the model may support clinical decision-making to optimize patient selection in whom anti-TNF can be withdrawn. Clinical validation is ongoing in a prospective randomized trial.Development and application of statistical models for medical scientific researc