Switching treatments from infliximab to adalimumab is an effective strategy for patients with Crohn's disease when infliximab becomes less effective. However, there are few reports on the long-term efficacy of switching from infliximab to adalimumab. In this study, we evaluated the long-term outcomes and related prognostic factors of switching from infliximab to adalimumab maintenance treatment.Methods:
Retrospective data were collected at our hospital between October 2010 and September 2015, from luminal Crohn's disease patients who switched from infliximab to adalimumab due to infliximab treatment failure. Patients who received adalimumab for <4 weeks were excluded. All patients received 160 mg of adalimumab on day 1, 80 mg at week 2, and 40 mg every other week from week 4. The effectiveness of adalimumab maintenance treatment was evaluated using the rate of sustained clinical benefit following adalimumab administration, which was estimated using the Kaplan–Meier method. Treatment failure was defined as one of 3 conditions, adalimumab discontinuation, dose escalation, or abdominal surgery for Crohn's disease. Prognostic factors associated with the rate of sustained clinical benefit were evaluated using log-rank tests and multivariate Cox regression analysis.Results:
Of the 65 patients included in this study (mean age, 35.3 yr), 30 were female. The mean duration of disease was 12.3 years. The mean C-reactive protein level was 2.00 mg/dL. Of the 65 patients, 45 patients had ileocolitis, 8 had ileitis, and 12 had colitis. In addition, 30 patients had stricturing disease, 8 had intra-abdominal fistulas, and 34 had perianal disease. Thirty-three patients were smokers. Concomitant treatment with immunomodulators, 5-aminosalicylic acid, elemental diet therapy, and prednisolone were administered to 39, 59, 31, and 12 patients, respectively. Before initiating adalimumab treatment, 41 patients had undergone at least one intestinal resection. The sustained clinical benefit rates at 1, 2, 3, and 4 years were 49%, 32%, 25%, and 22%, respectively. In the univariate analysis, significant prognostic factors for a lower rate of sustained clinical benefit were female gender, stricturing disease, and colitis type. These factors were also identified as independent predictors of sustained clinical benefit in the multivariate Cox regression analysis. The sustained clinical benefit rates at 1, 2, 3, and 4 years in patients of male gender, without stricturing disease, and with ileitis or ileocolitis type were 66%, 43%, 34%, and 27%; 60%, 39%, 31%, and 25%; and 52%, 36%, 30%, and 26%, respectively.Conclusions:
Switching treatment from infliximab to adalimumab was effective in approximately 50% of the patients with Crohn's disease whose infliximab treatment proved ineffective. However, adalimumab treatment failure was experienced by approximately 80% of patients over a 4-year period. Consideration should be provided to patients regarding female gender, presence of stricturing disease, and colitis type when switching from infliximab to adalimumab.