P599. Adalimumab as first-line anti-TNF treatment in pediatric Crohn's disease
J. Martín de Carpi1, E. Llerena1, V. Vila1, S. Pinillos1, V. Varea1, 1Hospital Sant Joan de Déu, Paediatric Gastroenterology, Barcelona, Spain
Adalimumab (ADA), monoclonal humanized anti-TNF antibody is usually used as a second-line therapy in pediatric Crohn's disease (CD) after Infliximab. ADA has shown its efficacy as first-line therapy in adults. Data on short- and long-term efficacy in Infliximab-naïve pediatric patients are limited.
Retrospective review of our CD pediatric patients (<18 years) treated with ADA as first anti-TNF. Efficacy on induction and maintenance of remission (absence of symptoms and PCDAI <10), improvement of nutritional status and safety, were evaluated. ADA induction dose was established according to basal weight (>30 kg: 160–80 mg; <30 kg: 80–40 mg). Standard maintenance dose: 40 mg every 2 weeks.
17 patients were included. Mean age at diagnosis: 11years 1 month (range 3–16y). Mean duration of the disease before ADA administration: 11 months (1–55). Mean follow-up after ADA initiation: 15.7 months. ADA was initiated after standard treatment failure (exclusive enteral nutrition and azathioprine [AZA]) in 14 patients, coexisting extraintestinal manifestations (2 patients) or intolerance to immunosuppressants (IS) (1 patient). Remission at week 4 was achieved in all patients with failure of previous medications (100%), and maintained at the end of the follow-up in 13. One patient required surgery after development of stenosis of the terminal ileum. Nine patients remain in clinical remission after 52 weeks follow-up. All the patients received initially concomitant AZA treatment except the patient with intolerance to IS. Six patients with combined treatment switched to ADA monotherapy after a median time of 11.8 months. Two patients required dose interval reduction to weekly ADA; both could return to standard dose later in the follow-up. Median CRP and ESR decreased from 51.5 to 5.5 mg/L and from 24.5 to 8.4 mm/h respectively on the 4th week after ADA initiation. Median weight gain after 6 months was 5.1 kg (1.8–8.8). An improvement in height for age after 6 months of treatment was also observed (median increase 2.65 cm). Two patients experienced mild local adverse reactions. No severe adverse reactions, infections or malignancies were reported.
ADA has shown efficacy and safety in inducing and maintaining remission in our anti-TNF naïve pediatric CD patients. An additional beneficial effect on weight gain and growth has been observed. Early use of ADA in our patients as compared to previous series could influence our results.