Background : Adalimumab ( ADA) is a fully human monoclonal antibody which binds with a high affinity and specificity to tumor necrosis factor (TNFα). Controlled clinical trials have demonstrated its efficacy and safety in the treatment of moderate-to-severe Crohn's disease (CD). However, long term experience with ADA in real-life clinical practice has rarely been reported. Objective: to assess the long term effectiveness and the safety of ADA in a multicenter cohort of patients with moderate-to-severe CD. Methods: Fifty five patients (21 men, 34 women), mean age 37.5 years (±11.4 years), median disease duration 12.7 years ( range 1-41 years) were treated with ADA and followed up over a period of 52 weeks (range 12-96 weeks, median 50 weeks). Thirty eight patients had previously been treated with infliximab (IFX). The ADA induction regimen was 160/80 mg in 31 patients and 80/ 40 mg in 24 patients. The clinical evolution during treatment was evaluated with the Harvey-Bradshaw Index (HBI) at week (W) 4-6, 12, 24 and 52. Patients were classified in three categories : remission (HBI < 4 pts) , response (reduction HBI > 3 pts) and non response. Results: On week 4-6, a response was demonstrated in 83.6 % patients and remission was obtained in 52.7%. The remission was maintained in 89.6% and 72.4% of the patients at W12 and W24, respectively. In per protocol analysis at W52, half of patients were still in
response and half had stopped ADA : 5/19 because of adverse events and 14/19 because of no response or loss of response. Thirteen patients (23.6%) needed a dose escalation after a mean interval of 7 months (range 1-24 month). The response rate at W4-6 was not influenced
by gender, smoking status, disease duration, localisation of disease, previous surgery, previous IFX treatment, the first month total ADA dose, or the first month ADA dose divided by body weight. Interestingly, however, the remission rate at W4-6 was significantly higher in patients intolerant (78.9%) to IFX, as compared to those who had lost response to IFX (42.1%; p=0.02). Overall ADA was well tolerated, 54.5% patients didn't report any side effects. The most common side effect was pain at the injection site (10.9%), followed by asthenia (9%) and infections (7.2%). Conclusion : ADA was effective and safe in clinical practice as induction and maintenance therapy for patients with moderate-to-severe CD.