Background: We have used Infliximab (INFLX) following intestinal transplantation (ITx) as a rescue agent for early, severe ACR (S-ACR), refractory ACR (R-ACR), and for treatment of chronic mucosal inflammation (CMI). This study aims to review our experience with INFLX in an effort to examine efficacy.

Methods: An IRB-approved, retrospective review of a prospectively maintained single-center database of all ITx recipients receiving INFLX was performed. INFLX therapy was used on a case-by-case basis based on clinical condition/indication starting in 2005. S-ACR was defined as Grade 4 or exfoliative acute rejection. R-ACR was defined as partially treated, ongoing ACR incompletely responsive to standard therapy. CMI was defined as an IBD-like condition including active enteritis with a lymphocyte predominant infiltrate and/or ulcerations not attributable to rejection. INFLX was typically administered at 5mg/kg/dose. Doses were administered at 6-8 week intervals for patients with CMI.

Results: 22 patients (12 children; 14 with liver-inclusive allografts) were treated with INFLX for 23 different episodes of allograft dysfunction: S-ACR (n= 5), R-ACR (n=8), and CMI (n=10). For S-ACR, the median time for INFLX after ITx was 35 (IQR 30, 44) days. All patients lost their allograft. For R-ACR, the median time for INFLX after ITx was 1.3 (1.0, 3.6) years. In combination with ATG, 3/8 recovered allograft function. For CMI, the median time to for INFLX after ITx was 2.7 (1.4, 4.7) years. These patient have received a median of 7 (4,13) infusions. 7/10 experienced clinical/pathological improvement while 3 had inadequate response. 1 patient stopped INFLX due to PTLD and 1 due to an infusion reaction.

Conclusion: INFLX has been an effective biologic agent for gastroenterology patients with IBD and has been reported to be effective in the treatment of ACR after ITx. Our experience indicates that IFLX is ineffective as a salvage therapy for S- ACR. It may have a role as an adjunct therapy for R-ACR when combined with ATG. INFLX appears to be quite effective in the management of post ITx CMI. Larger, multicenter studies should be considered to further investigate the efficacy of INFLX after ITx.