Please use this identifier to cite or link to this item:
Scopus Web of Science® Altmetric
Type: Journal article
Title: Genetic polymorphism of CYP1A2 but not total or free teriflunomide concentrations is associated with leflunomide cessation in rheumatoid arthritis
Author: Hopkins, A.
Wiese, M.
Proudman, S.
O'Doherty, C.
Upton, R.
Foster, D.
Citation: British Journal of Clinical Pharmacology, 2016; 81(1):113-123
Publisher: Wiley
Issue Date: 2016
ISSN: 1365-2125
Statement of
Ashley M. Hopkins, Michael D. Wiese, Susanna M. Proudman, Catherine E. O'Doherty, Richard N. Upton, David J. R. Foster
Abstract: AIM(S): Leflunomide, via its active metabolite teriflunomide, is used in rheumatoid arthritis (RA) treatment, yet approximately 20 to 40% of patients cease due to toxicity. The aim was to develop a time-to-event model describing leflunomide cessation due to toxicity within a clinical cohort and to investigate potential predictors of cessation such as total and free teriflunomide exposure and pharmacogenetic influences. METHODS: This study included individuals enrolled in the Early Arthritis inception cohort at the Royal Adelaide Hospital between 2000 and 2013 who received leflunomide. A time-to-event model in NONMEM was used to describe the time until leflunomide cessation and the influence of teriflunomide exposure and pharmacogenetic variants. Random censoring of individuals was simultaneously described. The clinical relevance of significant covariates was visualised via simulation. RESULTS: Data from 105 patients was analysed, with 34 ceasing due to toxicity. The baseline dropout hazard and baseline random censoring hazard were best described by step functions changing over discrete time intervals. No statistically significant associations with teriflunomide exposure metrics were identified. Of the screened covariates, carriers of the C allele of CYP1A2 rs762551 had a 2.29 fold increase in cessation hazard compared to non-carriers (95% CI 2.24 - 2.34, p = 0.016). CONCLUSIONS: A time-to-event model described the time between leflunomide initiation and cessation due to side effects. The C allele of CYP1A2 rs762551 was linked to increased leflunomide toxicity, while no association with teriflunomide exposure was identified. Future research should continue to investigate exposure-toxicity relationships, as well as potentially toxic metabolites. This article is protected by copyright. All rights reserved.
Keywords: Leflunomide; NONMEM; rheumatoid arthritis; teriflunomide; time-to-event
Rights: © 2015 The British Pharmacological Society
RMID: 0030034983
DOI: 10.1111/bcp.12760
Appears in Collections:Medicine publications

Files in This Item:
File Description SizeFormat 
hdl_95664.pdfAccepted version630.8 kBAdobe PDFView/Open

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.