P596 Adalimumab use in Paediatric Inflammatory Bowel Disease: A single centre real-life experience

Abstract

Abstract Background Anti-TNF-α, including infliximab and adalimumab (ADA), plays a crucial role in the treatment of Paediatric Inflammatory Bowel Disease (PIBD). This study evaluates the efficacy of ADA in children ≤ 19 years in a single European centre. Methods A 6-year retrospective analysis of prospectively collected data of PIBD patients treated with ADA (10/2015 onward). Wellbeing, clinical and laboratory findings were assessed at each visit. A mean, median and a standard deviation were calculated were applicable. ANOVA (analysis of variances) was used for evaluation of presence of statistically significant differences and a P-value ≤ 0.05 was regarded as such. Results ADA, all originator, was used in 31 patients. All of them were diagnosed with Crohn’s Disease (CD). The mean age at diagnosis was 14.6±2.8 years (range 6.6–18.2 years). The mean interval from diagnosis till commencement of ADA was 6.9 months (0.25–36 months). Step-up was used 17x and top-down 15x. A top-down approach was indicated in patients with extraintestinal manifestations, fistulizing disease, severe growth impairment and affections of the proximal gastrointestinal tract. Adjacent treatments at the time of commencement of ADA were azathioprine (18/31), CD exclusion diet (7/31), exclusive enteral nutrition (6/31), steroids (4/31), methotrexate and 5-aminosalicylates (both 3/31). Mean CRP at the time of ADA commencement was 8.8 mg/l (1.0–44.4 mg/l), ESR 21 mm/hour (1–66 mm/hour), leukocytes 8.3x109/l (3.3–22.0x109/l), haemoglobin 118.3 g/l (68–150 g/l), platelets 422x109/l (232–828 x109/l) and faecal calprotectin (FC) 901.1 μg/g (95.2–5041.9 μg/g). At the end of induction period, CRP, ESR and FC showed a significant decrease (P< 0.01). Blood count parameters failed to show that (P >0.05). Mean ADA trough levels at the end of induction period were 18.4±2.3 μg/ml. For maintenance of trough levels (≥7.5 μg/ml), weekly administration was required in 5 cases. During the follow-up period, surgical intervention was required 2x (ileocecal resection 1x and stricturoplasty 1x). Adverse side effects consisted of a skin reaction 1x and reversible hair loss 1x. Due to loss of response, 3 patients had to be switched out-of-class to ustekinumab. The mean time to loss of response since ADA commencement was 23.3 months (16–30 months). Antibody formation after 23 months of treatment led to switching one patient to infliximab. One patient was lost to follow-up. Conclusion These data show that ADA is effective in achieving laboratory and clinical remission in PIBD patients. Maintenance of trough levels may sometimes requite weekly administration of ADA. Loss of response may occur. Adverse reactions were minimal.