Predictors of response to Infliximab in children with luminal Crohn's disease.
OBJECTIVE
A significant proportion of patients with initial response to Inflximab (IFX), subsequently lose response (LOR). Multicentre paediatric studies report LOR in 33% to 50% with 3-5year follow-up. Our retrospective study examined durability of response and predictors of LOR.


METHODS
From our IBD database of 185 children with CD, 65 received IFX maintenance therapy for luminal or fistulising Crohn's disease between January, 2006 and April, 2013. 47 with luminal CD ≥1year follow-up after commencing IFX were included. We evaluated variables associated with response and describe outcomes on those remaining on IFX at four time points; before IFX, after induction, at 1year and at the last follow-up. Response was divided into sustained primary, recovered, durable (combined sustained primary and recovered) and complete LOR (discontinuation from LOR or intolerance).


RESULTS
Overall, 28/47 (60%) children sustained primary response over a median duration of 2.83years (1.6-4.4, IQR). 19/47 (40%) developed LOR (including 2 intolerant) at a median of 11months (9-19, IQR). Of 17 with LOR, 7 were successfully re-induced giving durable response (35/47, 74%); 6 failed dose intensification needing surgery (n=2), second anti-TNF (n=2) or both (n=2). 4 had surgery without dose intensification. LOR was associated with low BMI at diagnosis, lower height Z scores prior to induction, elevated CRP following induction (p=0.007) and failure to use concomitant IM (p=0.02).


CONCLUSIONS
The cumulative probability of durable response to IFX in luminal CD was 83%, 74% and 70% after 1, 2, and 3years on IFX maintenance therapy.
Queensland Children Medical Research Institute, Brisbane, QLD, Australia; Queensland Paediatric Gastroenterology Hepatology, Royal Children's Hospital, Brisbane, QLD, Australia. Electronic address: z.grover@uq.edu.au.
Zubin
Z
Grover
Queensland Paediatric Gastroenterology Hepatology, Royal Children's Hospital, Brisbane, QLD, Australia.
Rebecca
R
Biron
Queensland Paediatric Gastroenterology Hepatology, Royal Children's Hospital, Brisbane, QLD, Australia.
Nicholas
N
Carman
Queensland Children Medical Research Institute, Brisbane, QLD, Australia; University Of Queensland, Department of Paediatrics & Child Health, Brisbane, QLD, Australia.
Peter
P
Lewindon
D000293:Adolescent; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000627:therapeutic use*; D000911:Antibodies, Monoclonal / Q000627:therapeutic use*; D002648:Child; D003424:Crohn Disease / Q000188:drug therapy*; D005260:Female; D006801:Humans; D000069285:Infliximab; D008297:Male; D012189:Retrospective Studies; D017211:Treatment Failure; D016896:Treatment Outcome
D000894:Anti-Inflammatory Agents, Non-Steroidal; D000911:Antibodies, Monoclonal; D000069285:Infliximab
Crohn's disease; Immunomodulators; Infliximab; Loss of response; Paediatrics