Influence of polymorphisms and TNF and IL1ß serum concentration on the infliximab response in Crohn's disease and ulcerative colitis.

AIM: Inflammatory bowel diseases (IBD), such as Crohn's disease (CD) and ulcerative colitis (UC), are partially attributable to an increased secretion of proinflamatory cytokines, such as tumour necrosis factor (TNF) and interleukin-1ß (IL1ß), which play essential roles in the disease pathogenesis and are target molecules for specific therapy. Given the inter-individual variability in the response to the anti-TNF monoclonal antibody infliximab, the aim of our study was to explore the predictive value of TNF and/or IL1ß as surrogate markers of infliximab response. METHODS: Serial serum concentrations of TNF and IL1ß and TNF promoter region and IL1B polymorphisms were determined in 47 patients (29 CD and 18 UC) receiving infliximab and correlated with treatment response. RESULTS: Baseline serum concentrations of TNF and IL1ß were higher in UC patients than in CD patients (p = 0.0097 and 0.0024, respectively). CD patients showing <0.64 pg/ml IL1ß at baseline were more frequently responders than non-responders (p = 0.036), and the C allele of the IL1B polymorphism was associated with higher IL1ß serum concentrations (p = 0.026) and with poorer clinical remission after 14 weeks of infliximab treatment. No significant association was found between serum TNF concentration or TNF polymorphism and patient response to infliximab. CONCLUSION: This is the first study evaluating the pharmacogenetic role of the rs1143634 polymorphism of IL1B and TNF polymorphisms in infliximab-treated IBD patients. We found an association between the rs1143634 C allele and higher serum IL1ß concentrations and a lower response to infliximab treatment in CD patients that warrants the interest of future studies in larger and independent series.

Effects of polymorphisms in TRAILR1 and TNFR1A on the response to anti-TNF therapies in patients with rheumatoid and psoriatic arthritis.

OBJECTIVES: As the role of polymorphisms in death receptors (DRs) such as Tumor Necrosis Factor-related Apoptosis-inducing Ligand Receptor 1 (TRAIL-R1) and Tumor Necrosis Factor Receptor 1A (TNF-R1A) on the response to anti-TNF therapy remains unknown, we evaluated the association between TRAILR1 and TNFR1A gene polymorphisms (rs20575/C626G and rs767455/G36A) and the pharmacogenetics of patients with rheumatoid arthritis (RA) and psoriatic arthritis (PsA) treated with TNFα blockers. METHODS: One hundred and forty-five patients (90 RA and 55 PsA) treated with anti-TNFα therapy (RA: 75 infliximab, 8 etanercept, 7 adalimumab. PsA: 27 infliximab, 19 etanercept, 9 adalimumab) were genotyped for TRAILR1 and TNFR1A polymorphisms by allelic discrimination. The response to anti-TNFα was assessed by EULAR criteria. RESULTS: In RA, the TRAILR1 CC genotype was associated with a better response after 3 and 6 months of anti-TNFα treatment (CC: 91.7% vs. CG/GG: 62.2%; P=0.019, and CC: 82.6% vs. CG/GG: 56.1%; P=0.019, respectively). Similar results were observed in only infliximab-treated RA patients. With respect to the TNFR1A polymorphism, there was an association between the AA genotype and a poorer response at 3 months in RA patients (AA: 39.3% vs. AG/GG: 19.0%; P=0.04). In PsA, TRAILR1 CC genotype was only associated with EULAR response to infliximab at 6 months (CC: 71.4% vs CG/GG: 50%P=0.048). In contrast to RA, the TNFR1 polymorphism in PsA was associated with a better response at 3 months (AA 88% vs AG/GG 58.9%; P=0.04). CONCLUSIONS: This study provides the first evidence that a polymorphism in TRAILR1 influences the response to anti-TNFα therapy in RA and also suggests that TNFR1A polymorphism may have opposing effects on the response to anti-TNFα in RA and PsA.