Background Vedolizumab has proven efficiency in adults but data in paediatric inflammatory bowel disease (pIBD) is limited. We present the outcome of treatment with vedolizumab in refractory pIBD cohort.

Study Design Retrospective and ongoing prospective review of all patients commenced on Vedolizumab following loss of response to anti-tumour necrosis factor [TNF] between Nov 2017 and Nov 2020.

Aims and Objectives The primary outcome was remission at Week 14 and last follow up (wPCDAI/PUCAI<10) from commencing vedolizumab. The secondary outcomes were to review trend of biochemical makers, surgical interventions, and adverse effects.

Results 11 children received vedolizumab (6[54%] males), mean age at time of diagnosis 12.45(8.34–15.48) with a median(IQR) time from diagnosis of 2.68(1.79–5.28)years; 6[54%] Crohn’s disease [CD] and 5[46%] Ulcerative colitis/IBD Unclassified [UC/IBDU] (table 1).

For CD; 5/6 was treated previously with anti-TNF [40% primary failure, 60% secondary failure], all had colonic disease, 3/6 upper GI involvement and 3/6 perianal disease. One child with Bruton’s agammaglobulinemia was anti-TNF naïve when commenced on vedolizumab. All UC children were treated with anti-TNF [40% primary failure, 60% secondary failure], 80% had pan-colitis.

Median age at time of commencing vedolizumab (V0) was 14.99(13.0–17.6). Baseline characteristics at V0; faecal calprotectin(FC) 2851(92–6000), Hb 114(96–146), ESR 22(4–90), albumin 39(27–46) and CRP 16.7(4–39.5). 4/11(36%) required surgery, three of whom had colectomy. 8/11 remained on immunomodulators with vedolizumab. Transient raised transaminases and eczema was reported once and low mood with suboptimal response noted once. 6/11(54%) were in remission 14 weeks from commencing vedolizumab (V14) and 4/11(36%) were excluded. At last follow up from commencing vedolizumab (VF), median years 2.21(0.78–3.43), 3 remained in remission.

In CD cohort, one child had a defunctioning ileostomy and remained in steroid free remission (SFR) at V14 and VF (3.43 years) on vedolizumab monotherapy. One had colectomy (FC-3296 wPCDAI-60), steroid dependency compounded by methotrexate induced interstitial nephritis and vedolizumab was discontinued at VF (2.19 years). Two continue to have active disease at V14 after commencing vedolizumab. One had SFR at V14 and was transitioned at 2 years (FC-2585, wPCDAI-25) on vedolizumab. One with anti-TNF resistant disease, achieved clinical remission 9 months after starting vedolizumab (wPCDAI 2.5, FC 598) before being transitioned.

In UC cohort, two had vedolizumab primary non-response needing subtotal colectomy. One patient with PUCAI 5 at V14 needed regime intensification for low vedolizumab levels but had active disease (PUCAI-25, FC-366) when transitioned at VF (2.06 years). One patient, who achieved remission whilst on steroid at V14, remains in SFR at VF (0.58 years) on concomitant immunomodulation and optimal vedolizumab level at end of induction (>19). One who was lost to follow-up during COVID, was transitioned on 4 weekly vedolizumab regime.

Conclusion At V14, 54% of patients achieved clinical remission and we see significant improvement with PUCAI/PCDAI scores and faecal calprotectin in both UC and CD cohort. We are continuing this study over a longer period to achieve a larger cohort.