Biomarkers for Optimization and Personalization of Anti-TNFs in Pediatric Inflammatory Bowel Disease

The Effect of Polymorphisms and Other Biomarkers on Infliximab Exposure in Paediatric Inflammatory Bowel Disease: Development of a Population Pharmacokinetic Model

BACKGROUND

Therapeutic drug monitoring (TDM) of infliximab has been shown to be a effective strategy for inflammatory bowel disease (IBD). Population pharmacokinetic (PopPK) modeling can predict trough concentrations for individualized dosing.

OBJECTIVE

The aim of this study was to develop a PopPK model of infliximab in a paediatric population with IBD, assessing the effect of single nucleotide polymorphisms (SNPs) and other biomarkers on infliximab clearance.

METHODS

This observational and ambispective single-centre study was conducted in paediatric patients with IBD treated with infliximab between July 2016 and July 2022 in the Paediatric Gastroenterology Service of the Hospital Universitari Vall d'Hebron (HUVH) (Spain). Demographic, clinical, and analytical variables were collected. Twenty SNPs potentially associated with variations in the response to infliximab plasma concentrations were analysed. infliximab serum concentrations and antibodies to infliximab (ATI) were determined by ELISA. PopPK modelling was performed using nonlinear mixed-effects analysis (NONMEM).

RESULTS

Thirty patients (21 males) were included. The median age (range) at the start of infliximab treatment was 13 years (16 months to 16 years). A total of 190 samples were obtained for model development (49 [25.8%] during the induction phase). The pharmacokinetics (PK) of infliximab were described using a two-compartment model. Weight, erythrocyte sedimentation rate (ESR), faecal calprotectin (FC), and the SNP rs1048610 (ADAM17) showed statistical significance for clearance (CL), and albumin for inter-compartmental clearance (Q). Estimates of CL1 (genotype 1-AA), CL2 (genotype 2-AG), CL3 (genotype 3-GG), Q, Vc, and Vp (central and peripheral distribution volumes) were 0.0066 L/h/46.4 kg, 0.0055 L/h/46.4 kg, 0.0081 L/h/46.4 kg, 0.0029 L/h/46.4 kg, 0.6750 L/46.4 kg, and 1.19 L/46.4 kg, respectively. The interindividual variability (IIV) estimates for clearance, Vc, and Vp were 19.33, 16.42, and 36.02%, respectively.

CONCLUSIONS

A popPK model utilising weight, albumin, FC, ESR, and the SNP rs1048610 accurately predicted infliximab trough concentrations in children with IBD.

Predicting pediatric Crohn's disease based on six mRNA-constructed risk signature using comprehensive bioinformatic approaches

Crohn's disease (CD) is a recurrent, chronic inflammatory condition of the gastrointestinal tract which is a clinical subtype of inflammatory bowel disease for which timely and non-invasive diagnosis in children remains a challenge. A novel predictive risk signature for pediatric CD diagnosis was constructed from bioinformatics analysis of six mRNAs, adenomatosis polyposis downregulated 1 (APCDD1), complement component 1r, mitogen-activated protein kinase kinase kinase kinase 5 (MAP3K5), lysophosphatidylcholine acyltransferase 1, sphingomyelin synthase 1 and transmembrane protein 184B, and validated using samples. Statistical evaluation was performed by support vector machine learning, weighted gene co-expression network analysis, differentially expressed genes and pathological assessment. Hematoxylin-eosin staining and immunohistochemistry results showed that APCDD1 was highly expressed in pediatric CD tissues. Evaluation by decision curve analysis and area under the curve indicated good predictive efficacy. Gene Ontology, Kyoto Encyclopedia of Genes and Genomes and gene set enrichment analysis confirmed the involvement of immune and cytokine signaling pathways. A predictive risk signature for pediatric CD is presented which represents a non-invasive supplementary tool for pediatric CD diagnosis.

Association between HLA DNA Variants and Long-Term Response to Anti-TNF Drugs in a Spanish Pediatric Inflammatory Bowel Disease Cohort

The genetic polymorphisms rs2395185 and rs2097432 in HLA genes have been associated with the response to anti-TNF treatment in inflammatory bowel disease (IBD). The aim was to analyze the association between these variants and the long-term response to anti-TNF drugs in pediatric IBD. We performed an observational, multicenter, ambispective study in which we selected 340 IBD patients under 18 years of age diagnosed with IBD and treated with anti-TNF drugs from a network of Spanish hospitals. Genotypes and failure of anti-TNF drugs were analyzed using Kaplan-Meier curves and Cox logistic regression. The homozygous G allele of rs2395185 and the C allele of rs2097432 were associated with impaired long-term response to anti-TNF drugs in children with IBD after 3 and 9 years of follow-up. Being a carrier of both polymorphisms increased the risk of anti-TNF failure. The SNP rs2395185 but not rs2097432 was associated with response to infliximab in adults with CD treated with infliximab but not in children after 3 or 9 years of follow-up. Conclusions: SNPs rs2395185 and rs2097432 were associated with a long-term response to anti-TNFs in IBD in Spanish children. Differences between adults and children were observed in patients diagnosed with CD and treated with infliximab.

JNK pathway-associated phosphatase illustrates low expression and negative correlations with inflammation, disease activity, and T-helper 17 cells in inflammatory bowel disease children

Background

C‐Jun N‐terminal kinase pathway‐associated phosphatase (JKAP) modulates the T cell receptor and mitogen‐activated protein kinase pathway‐mediated autoimmunity, thus participating in the pathogenesis of autoimmune diseases. This study aimed to explore the clinical implication of JKAP in inflammatory bowel disease (IBD) children.

Methods

C‐Jun N‐terminal kinase pathway‐associated phosphatase, tumor necrosis factor‐α (TNF‐α), interleukin‐23, interferon‐γ (T‐helper 1 secreted cytokine), and interleukin‐17A (T‐helper 17 secreted cytokine) in serum samples from 140 IBD children (including 60 Crohn's disease (CD) children and 80 ulcerative colitis (UC) children) were detected by ELISA. Meanwhile, JKAP from serum samples of 10 healthy controls (HCs) was also detected by ELISA.

Results

C‐Jun N‐terminal kinase pathway‐associated phosphatase was reduced in CD children (median (interquartile range (IQR)): 51.6 (36.8–69.5) pg/ml) and UC children (median (IQR): 57.5 (43.4–78.5) pg/ml) compared with HCs (median (IQR): 101.8 (70.0–143.2) pg/ml) (both p < 0.05). In CD children, JKAP was negatively correlated with C‐reactive protein (CRP) (p = 0.016) and erythrocyte sedimentation rate (ESR) (p = 0.029); while in UC children, JKAP was also negatively correlated with CRP (p = 0.006) and ESR (p = 0.022). Regarding the correlation of JKAP with disease activity, it presented negative correlations with PCDAI (p = 0.001) and PUCAI (p = 0.002). Besides, JKAP was negatively related to TNF‐α (both p < 0.05) but not interleukin‐23 (both p>0.05) in CD and UC children. Additionally, JKAP was not correlated with interferon‐γ in CD or UC children (both p>0.05), while negatively correlated with interleukin‐17A in CD and UC children (both p < 0.05).

Conclusion

C‐Jun N‐terminal kinase pathway‐associated phosphatase shows low expression and negative correlations with inflammation, disease activity, and T‐helper 17 cells in IBD children.