RESUMO
BACKGROUND: Infliximab (IFX) is the first-line treatment for patients with Crohn's disease (CD) and is noted for its relatively high cost. The therapeutic efficacy of IFX has noticeable individual differences. Known single-gene polymorphisms (SNPs) are inadequate for predicting non-response to IFX. In this study, we aimed to identify new genetic factors associated with IFX-therapy failure and to predict non-response to IFX by developing a multivariate predictive model. METHODS: In this retrospective study, we collected and analysed the data of Chinese patients with CD who received IFX therapy at one hospital between June 2013 and June 2019. Primary non-response (PNR) and non-durable response (NDR) were evaluated using a simple endoscopic score for CD (SES-CD). A total of 125 SNPs within 44 genes were genotyped. A multivariate logistic-regression model was established to predict non-response to IFX. An area-under-the-receiver-operating-characteristics curve (AUROC) was applied to evaluate the predictive model performance. RESULTS: Forty-two of 206 (20.4%) patients experienced PNR and 15 of 159 (9.4%) patients experienced NDR. Nine SNPs were associated with PNR (P < 0.05). A PNR predictive model was established, incorporating 2-week high-sensitivity C-reactive protein (hs-CRP), rs61886887, rs61740234, rs357291, rs2269330, and rs111504845, and the AUROC on training and testing data sets were 0.818 (P < 0.001) and 0.888 (P < 0.001), respectively. At week 14, hs-CRP levels ≥ 2.25 mg/L were significantly associated with NDR (AUROC = 0.815, P < 0.001). PNR-associated SNPs were not mutually associated with NDR, suggesting distinct mechanisms between PNR and NDR. CONCLUSION: Genetic polymorphisms are significantly associated with response to IFX among Chinese CD patients.
RESUMO
BACKGROUND: Trough levels of the post-induction serum infliximab (IFX) are associated with short-term and long-term responses of Crohn's disease patients to IFX, but the inter-individual differences are large. We aimed to elucidate whether single gene polymorphisms (SNPs) within FCGR3A, ATG16L1, C1orf106, OSM, OSMR, NF-κB1, IL1RN, and IL10 partially account for these differences and employed a multivariate regression model to predict patients' post-induction IFX levels. METHODS: The retrospective study included 189 Crohn's disease patients undergoing IFX therapy. Post-induction IFX levels were measured and 41 tag SNPs within eight genes were genotyped. Associations between SNPs and IFX levels were analysed. Then, a multivariate logistic-regression model was developed to predict whether the patients' IFX levels achieved the threshold of therapy (3 µg/mL). RESULTS: Six SNPs (rs7587051, rs143063741, rs442905, rs59457695, rs3213448, and rs3021094) were significantly associated with the post-induction IFX trough level (P = 0.015, P < 0.001, P = 0.046, P = 0.022, P = 0.011, P = 0.013, respectively). A multivariate prediction model of the IFX level was established by baseline albumin (P = 0.002), rs442905 (P = 0.025), rs59457695 (P = 0.049), rs3213448 (P = 0.056), and rs3021094 (P = 0.047). The area under the receiver operating characteristic curve (AUROC) of this prediction model in a representative training dataset was 0.758. This result was verified in a representative testing dataset, with an AUROC of 0.733. CONCLUSIONS: Polymorphisms in C1orf106, IL1RN, and IL10 play an important role in the variability of IFX post-induction levels, as indicated in this multivariate prediction model of IFX levels with fair performance.
