S0707 The Use of Combination Vedolizumab and Ustekinumab in Crohn's Disease: A Retrospective Cohort Study

INTRODUCTION: There is limited data on the use of more than one biologic in the treatment of patients with inflammatory bowel disease (IBD). The aim of our study was to determine the effectiveness and safety of combining vedolizumab (VDZ) and ustekinumab (UST) in patients with Crohn's disease (CD). METHODS: We collected data on 30 patients with CD who received treatment with a combination of VDZ and UST from 2015 to 2019 for persistent disease activity or concomitant rheumatologic or dermatologic disease. Clinical scoring and laboratory markers (ESR, CRP, albumin, and vitamin D) were collected at baseline (prior to starting combination therapy) and at follow up (after at least two months on combination therapy). Endoscopic data was collected within 6 months prior to initiation of combination therapy and at follow up (after at least two months on combination therapy). Adverse events were documented. The primary outcome was effectiveness defined by improvement in laboratory parameters, clinical, and endoscopic scoring; the secondary outcome was safety. RESULTS: The mean age was 37 (+/-12.2) years, 63% were female, 73% Caucasian, with a disease duration of 14 (+/-10.6) years. Patients had failed therapy with a median of 2 (2–3) previous biologic medications. The mean ESR decreased, 42.8 vs 27.3, P = 0.04, and mean albumin improved, 3.4 vs 4.0, P = 0.0005. The median HBI score improved from 7 to 5, P = 0.004 at follow up. There was no significant improvement in endoscopic score at follow up, however 50% of the group did not yet have follow up available. There were 5 serious adverse events (SAE), and no deaths. On multivariate analysis, immunomodulator use, longer disease duration, increasing age, and albumin were found to be risk factors for serious infection. CONCLUSION: Combination biologic therapy with VDZ and UST may be an effective option for CD patients with refractory disease or concomitant autoimmune disease inadequately controlled by biologic monotherapy. There appears to be an increased risk of serious infection compared to biologic monotherapy, however this risk might be minimized by discontinuing immunomodulators prior to the initiation of combination therapy. Larger prospective studies are needed to confirm these findings.Table 1Table 2