We performed a retrospective cohort study of 200 patients with CD (100 treated with IFX and 100 treated with ADA, starting in 2006 or later) who had not received anti-tumor necrosis factor ¦Á agents previously; the patients were identified from databases of 6 hospitals in The Netherlands. The groups were matched carefully for indication, duration of disease, age, and Montreal classification. The primary end point was the steroid-free clinical response, defined by a combination of multiple clinical parameters, after 1 year.
Of the total patient population, 63.5 % and 45 % had a clinical response after 1 and 2 years, respectively. There were no significant differences between treatment groups: at 1 and 2 years, 62 % and 41 % of those receiving ADA vs 65 % and 49 % of those receiving IFX had responses, respectively. Kaplan-Meier curves showed identical decreases in response rates over time. Combining IFX or ADA with immunomodulator therapy was associated with a higher clinical response than monotherapy, although this was only significant among patients who received IFX (P = .03). There were no differences in numbers of side effects or opportunistic infections.
The effectiveness of ADA or IFX treatment in anti-tumor necrosis factor ¦Á-naive patients with CD is comparable after 1 and 2 years of follow-up evaluation. The efficacies of IFX and ADA each seem to increase when given with immunomodulator therapy, although only significantly for IFX.