Infliximab Treatment for Steroid-Refractory Acute Graft-Versus-Host Disease After Reduced-Intensity Cord Blood Transplantation in Adults
Authors: Ishiwata Kazuya , Nishida Aya , Ota Hikari , Ikebe Taichi , Tsuji Masanori , Yamamoto Hisashi , Asano-Mori Yuki , Uchida Naoyuki , Izutsu Koji , Taniguchi Shuichi 
Published: October 2019

Abstract
Abstract 4553

Introduction
Acute graft versus host disease (GVHD) remains the most frequent complication after allogeneic hematopoietic stem cell transplantation (SCT). In reduced intensity cord blood transplantation (CBT) previous studies have reported a lower incidence of severe acute GVHD compared with conventional allo-SCT. However, in these studies the incidences of grade II-IV acute GVHD varied widely from 26% to 51% (H.Narimatsu Stem cell int. 2011: 607569). In particular, post transplant immune disorders, including early immune reactions (PIR) and acute GVHD, are potential complications following CBT in adult patients. Such reactions might increase the risk of organ dysfunction, leading to high rates of transplantation-related mortality, particularly in patients who do not respond to primary therapy, which usually consists of steroids. Infliximab, a chimeric monoclonal antibody against tumor necrosis factor alpha, has shown activity against steroid refractory acute GVHD.

Patients and Methods
We retrospectively reviewed 275 patients who underwent single-unit reduced intensity cord blood transplantation consecutively from March 2007 to December 2011 at our institute. Patients in whom PIR or acute GVHD developed received methylprednisolone 1–2 mg/kg per day. If no partial or complete resolution of symptoms occurred, they were considered steroid-refractory and proceeded to infliximab treatment. The dose of infliximab was 5 mg/kg/day once weekly for at least 1 course. An antifungal drug, itraconazole or micafungin or voriconazole was used until all immunosuppressive drus were withdrawn.

Results
In this study we retrospectively evaluated 54 patients who had steroid refractory acute GVHD. Of these, 21 who received infliximab were analyzed. GVHD prophylaxis was with only tacrolimus(n=15) and mycophenolate mofetil+tacrolimus(n=6). All of them developed grade III to IV GVHD. Median follow-up time of survivors was 548 days (range, 222–1152). The overall response rate was 62% (n=13), and 9 patients (43%) experienced complete response (CR). 5 patients (24%) did not respond and 3 (14%) had progressive GVHD. The Kaplan-Meier estimate of overall survival was 31%, with no signs of chronic GVHD (n=2). Four patients who responded subsequently died, one of exacerbation of GVHD, three of infections. All the 8 unresponsive patients died of GVHD or infections. Five patients (21%) had non-Candida invasive fungal infections. Sixteen patients(79%) had bacterial infections.

Conclusion
Infliximab was well tolerated and active for the treatment of steroid-resistant acute GVHD even following reduced intensity cord blood transplantation. However, it is associated with a high rate of infections. Controlled studies to assess the pharmacokinetics and most effective dosing regimen of infliximab for the treatment of steroid refractory acute GVHD are warranted.

Disclosures:
No relevant conflicts of interest to declare.