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Ribeiro AC, Gerheim PSAS, Chebli JMF, Nascimento JWL, de Faria Pinto P. The Role of Pharmacogenetics in the Therapeutic Response to Thiopurines in the Treatment of Inflammatory Bowel Disease: A Systematic Review. J Clin Med 2023; 12:6742. [PMID: 37959208 PMCID: PMC10649589 DOI: 10.3390/jcm12216742] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2023] [Revised: 09/26/2023] [Accepted: 10/07/2023] [Indexed: 11/15/2023] Open
Abstract
This study focuses on the use of thiopurines for treating inflammatory bowel diseases (IBD). These drugs undergo enzymatic changes within the body, resulting in active and inactive metabolites that influence their therapeutic effects. The research examines the role of genetic polymorphisms in the enzyme thiopurine S-methyltransferase (TPMT) in predicting the therapeutic response and adverse effects of thiopurine treatment. The TPMT genotype variations impact the individual responses to thiopurines. Patients with reduced TPMT activity are more susceptible to adverse reactions (AEs), such leukopenia, hepatotoxicity, pancreatitis, and nausea, which are common adverse effects of thiopurine therapy. The therapeutic monitoring of the metabolites 6-thioguanine nucleotides (6-TGN) and 6-methyl mercaptopurine (6-MMP) is proposed to optimize treatment and minimize AEs. Patients with higher 6-TGN levels tend to have better clinical responses, while elevated 6-MMP levels are linked to hepatotoxicity. Genotyping for TPMT before or during treatment initiation is suggested to tailor dosing strategies and enhance treatment efficacy while reducing the risk of myelosuppression. In conclusion, this study highlights the importance of considering genetic variations and metabolite levels in optimizing thiopurine therapy for IBD patients, focusing on balance therapeutic efficacy with the prevention of adverse effects and contributing to personalized treatment and better patient outcomes.
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Affiliation(s)
- Aline C. Ribeiro
- Department of Pharmaceutical Sciences, Faculty of Pharmacy, Federal University of Juiz de Fora, Juiz de Fora 36036-900, Minas Gerais, Brazil;
| | - Pâmela S. A. S. Gerheim
- Department of Pharmacology, Federal University of Juiz de Fora, Juiz de Fora 36036-900, Minas Gerais, Brazil;
| | - Julio Maria Fonseca Chebli
- Division of Gastroenterology, Department of Internal Medicine, Federal University of Juiz de Fora, Juiz de Fora 36036-900, Minas Gerais, Brazil;
| | - Jorge Willian L. Nascimento
- Laboratory of Clinical and Experimental Pharmacology, Department of Pharmacology, Federal University of Juiz de Fora, Juiz de Fora 36036-900, Minas Gerais, Brazil
| | - Priscila de Faria Pinto
- Department of Biochemistry, Institute of Biological Sciences, Federal University of Juiz de Fora, Juiz de Fora 36036-900, Minas Gerais, Brazil
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2
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Kohli A, Moss AC. Personalizing therapy selection in inflammatory bowel disease. Expert Rev Clin Immunol 2023; 19:431-438. [PMID: 37051666 DOI: 10.1080/1744666x.2023.2185605] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/14/2023]
Abstract
INTRODUCTION Inflammatory bowel disease (IBD) is a complex disease, caused by aberrant immune responses to environmental stimuli where genetic, metabolomic, and environmental variables interact to cause mucosal inflammation. This review sheds light on the different drug and patient related factors that affect personalization of biologics in IBD treatment. AREAS COVERED We utilized the online research database PubMed to carry out literature search pertaining to therapies in IBD. We incorporated a combination of primary literature as well as review articles and meta-analyses in writing this clinical review. In this paper, we discuss the mechanisms of action for different biologics, the genotype and phenotype of patients, and pharmacokinetics/pharmacodynamics of drugs, as factors that influence response rates. We also touch upon the role of artificial intelligence in treatment personalization. EXPERT OPINION The future of IBD therapeutics is one of precision medicine, based on the identification of aberrant signaling pathways unique to individual patients as well as exploring the exposome, diet, viruses, and epithelial cell dysfunction as part of disease pathogenesis. We need global cooperation for pragmatic study designs as well as equitable access to machine learning/artificial intelligence technology to reach the unfulfilled potential of IBD care.
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Affiliation(s)
- Arushi Kohli
- Division of Gastroenterology and Hepatology, Boston Medical Center, Boston, MA, USA
| | - Alan C Moss
- Division of Gastroenterology and Hepatology, Boston Medical Center, Boston, MA, USA
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3
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Park J, Cheon JH. Updates on conventional therapies for inflammatory bowel diseases: 5-aminosalicylates, corticosteroids, immunomodulators, and anti-TNF-α. Korean J Intern Med 2022; 37:895-905. [PMID: 35882566 PMCID: PMC9449200 DOI: 10.3904/kjim.2022.132] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/04/2022] [Accepted: 05/13/2022] [Indexed: 12/03/2022] Open
Abstract
The incidence and prevalence of inflammatory bowel diseases (IBDs) are rapidly increasing worldwide. IBDs are considered an emerging problem not only in Western countries but also in developing counties. The relapses and complications of active IBD mandate various medications. Nevertheless, hospitalization, emergency room visits, or surgery may be required, resulting in a socioeconomic burden. Great advances have been made in the development of new therapeutic options for IBD to achieve induction and maintenance remission. Nevertheless, conventional therapy is still the mainstay in the treatment of IBD. This review article provides an update on recent advances in conventional therapies, including 5-aminosalicylates, corticosteroids, immunomodulators, and anti-tumor necrosis factor-α agents to treat IBD.
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Affiliation(s)
- Jihye Park
- Department of Internal Medicine, Yonsei University College of Medicine, Seoul,
Korea
| | - Jae Hee Cheon
- Department of Internal Medicine, Yonsei University College of Medicine, Seoul,
Korea
- Institute of Gastroenterology, Yonsei University College of Medicine, Seoul,
Korea
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4
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Cytotoxicity of Thiopurine Drugs in Patients with Inflammatory Bowel Disease. TOXICS 2022; 10:toxics10040151. [PMID: 35448412 PMCID: PMC9026123 DOI: 10.3390/toxics10040151] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/11/2022] [Revised: 03/11/2022] [Accepted: 03/17/2022] [Indexed: 02/04/2023]
Abstract
The effectiveness of thiopurine drugs in inflammatory bowel disease (IBD) was confirmed more than a half-century ago. It was proven that these can be essential immunomodulatory medications. Since then, they have been used routinely to maintain remission of Crohn’s disease (CD) and ulcerative colitis (UC). The cytotoxic properties of thiopurines and the numerous adverse effects of the treatment are controversial. However, the research subject of their pharmacology, therapy monitoring, and the search for predictive markers are still very relevant. In this article, we provide an overview of the current knowledge and findings in the field of thiopurines in IBD, focusing on the aspect of their cytotoxicity. Due to thiopurines’ benefits in IBD therapy, it is expected that they will still constitute an essential part of the CD and UC treatment algorithm. More studies are still required on the modulation of the action of thiopurines in combination therapy and their interaction with the gut microbiota.
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5
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Deben DS, Wong DR, van Bodegraven AA. Current status and future perspectives on the use of therapeutic drug monitoring of thiopurine metabolites in patients with inflammatory bowel disease. Expert Opin Drug Metab Toxicol 2022; 17:1433-1444. [PMID: 35023443 DOI: 10.1080/17425255.2021.2029406] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
INTRODUCTION Despite new treatment options for inflammatory bowel disease (IBD), conventional thiopurines remain a common treatment option for maintaining remission, particularly in non-Westernized countries. Therapeutic drug monitoring (TDM) is advised in standard care for optimizing therapy strategies to improve effectiveness, reveal nonadherence and reduce toxicity. Still, the rationale of TDM is debated. AREAS COVERED Key insights on TDM of thiopurine metabolites are discussed. The pharmacology of thiopurines is described, emphasizing the interindividual differences in pharmacogenetics, pharmacokinetics and pharmacodynamics. Pharmacological differences between conventional thiopurines and tioguanine are outlined. Finally, several optimization strategies for thiopurine therapy in IBD are discussed. EXPERT OPINION TDM has been a useful, but limited, tool to individualize thiopurine therapy. Pharmacokinetic data on the active thiopurine metabolites, derived from measurements in erythrocytes, associated with clinical response only partially predict effectiveness and toxicity. An additional pharmacodynamic marker, such as Rac1/pSTAT3 expression in leukocytes, may improve applicability of TDM in the future.
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Affiliation(s)
- Debbie S Deben
- Dept. of Clinical Pharmacy, Clinical pharmacology and Toxicology, Zuyderland Medical Centre, Sittard-Geleen/Heerlen, The Netherlands
| | - Dennis R Wong
- Dept. of Clinical Pharmacy, Clinical pharmacology and Toxicology, Zuyderland Medical Centre, Sittard-Geleen/Heerlen, The Netherlands
| | - Adriaan A van Bodegraven
- Dept. of Gastroenterology, Geriatrics, Internal and Intensive Care Medicine (Co-MIK), Zuyderland Medical Centre Sittard-Geleen/Heerlen, The Netherlands.,Dept. of Gastroenterology and Hepatology, Amsterdam, The Netherlands
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Assessing aCCess to Investigations in Inflammatory Bowel Disease (ACCID): results from an international survey. Eur J Gastroenterol Hepatol 2021; 33:e837-e842. [PMID: 35048653 DOI: 10.1097/meg.0000000000002276] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/10/2022]
Abstract
BACKGROUND Multiple investigations are available to aid the diagnosis and monitoring of disease activity in inflammatory bowel disease (IBD). Fecal calprotectin (FC) is an established surrogate for intestinal inflammatory activity. Therapeutic drug monitoring (TDM) including thiopurine metabolites, anti-tumor necrosis factor (TNF) levels and antidrug antibody measurements are a step toward personalized medicine in IBD, but face access barriers. We aimed to assess test availability and barriers for these investigations in European practice. METHODS Five-hundred questionnaires were distributed to workshop participants at the 11th Congress of the European Crohn's and Colitis Organisation (ECCO). Access to FC, TDM for thiopurines and anti-tumor necrosis factor agents, as well as factors associated with usage and barriers to access were recorded. RESULTS Responses were obtained from 195 attendees from 38 countries across a range of practices, healthcare settings and levels of experience. FC was available to 92.3% while access to anti-TNF (78.9%, P = 0.02 vs. thiopurine TDM, P = 0.0002 vs. FC) and thiopurine TDM (67.7%, P = 0.0001) were less widespread. Cost was a frequently cited barrier to test access or usage, with access having a significant West-East and North-South divide across all three investigations. The strongest independent predictor of access to all tests was healthcare spending per capita (P = 0.005 for FC; P < 0.0001 for both TDM). CONCLUSION FC, anti-TNF and thiopurine TDM are increasingly incorporated as part of routine practice in IBD care across Europe and have the potential to impact positively on patient care. However, access barriers remain of which we found test cost the most significant with the investment required to reduce these barriers.
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Bayoumy AB, Mulder CJJ, Loganayagam A, Sanderson JD, Anderson S, Boekema PJ, Derijks LJJ, Ansari AR. Relationship Between Thiopurine S-Methyltransferase Genotype/Phenotype and 6-Thioguanine Nucleotide Levels in 316 Patients With Inflammatory Bowel Disease on 6-Thioguanine. Ther Drug Monit 2021; 43:617-623. [PMID: 34521801 PMCID: PMC8437045 DOI: 10.1097/ftd.0000000000000869] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Accepted: 01/16/2021] [Indexed: 12/16/2022]
Abstract
BACKGROUND In inflammatory bowel disease (IBD), conventional thiopurine users cease treatment in 60% of cases within 5 years, mostly because of adverse events or nonresponse. In this study, the authors aimed to investigate the role of 6-thioguanine nucleotide (TGN) measurements, geno/phenotyping of thiopurine S-methyltransferase (TPMT), and their mutual relationship with TG therapy in IBD. METHODS An international retrospective, multicenter cohort study was performed at 4 centers in the Netherlands (Máxima Medical Centre) and the United Kingdom (Guy's and St. Thomas' Hospital, Queen Elizabeth Hospital, and East Surrey Hospital). RESULTS Overall, 526 6-TGN measurements were performed in 316 patients with IBD. The median daily dosage of TG was 20 mg/d (range 10-40 mg/d), and the median duration of TG use was 21.1 months (SD, 28.0). In total, 129 patients (40.8%) had a known TPMT status. In the variant-type and wild-type TPMT genotype metabolism groups, median 6-TGN values were 1126 [interquartile range (IQR) 948-1562] and 467.5 pmol/8 × 10E8 red blood cells (RBCs) (IQR 334-593). A significant difference was observed between the 2 groups (P = 0.0001, t test). For TPMT phenotypes, in the slow, fast, and normal metabolism groups, the median 6-TGN values were 772.0 (IQR 459-1724), 296.0 (IQR 200-705), and 774.5 pmol/8 × 10E8 RBCs (IQR 500.5-981.5), with a significant difference observed between groups (P < 0.001, analysis of variance). CONCLUSIONS Our findings indicated that TPMT measurements at TG initiation can be useful but are not necessary for daily practice. TPMT genotypes and phenotypes are both associated with significant differences in 6-TGN levels between metabolic groups. However, the advantage of TG remains that RBC 6-TGN measurements are not crucial to monitor treatments in patients with IBD because these measurements did not correlate with laboratory result abnormalities. This presents as a major advantage in countries where patients cannot access these diagnostic tests.
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Affiliation(s)
- Ahmed B. Bayoumy
- Department of Gastroenterology and Hepatology, Amsterdam UMC, VU University Medical Centre, Amsterdam, The Netherlands
| | - Chris J. J. Mulder
- Department of Gastroenterology and Hepatology, Amsterdam UMC, VU University Medical Centre, Amsterdam, The Netherlands
| | - Aathavan Loganayagam
- Department of Gastroenterology, Queen Elizabeth Hospital, Woolwich, United Kingdom
| | - Jeremy D. Sanderson
- Department of Gastroenterology, Guy's and St Thomas' NHS Foundation Trust, London, United Kingdom
| | - Simon Anderson
- Department of Gastroenterology, Guy's and St Thomas' NHS Foundation Trust, London, United Kingdom
| | - Paul J. Boekema
- Department of Gastroenterology, Máxima Medical Centre, Veldhoven, The Netherlands
| | - Luc J. J. Derijks
- Department of Clinical Pharmacy and Pharmacology, Máxima Medical Centre, Veldhoven, The Netherlands; and
| | - Azhar R. Ansari
- Department of Gastroenterology, Surrey and Sussex NHS, East Surrey Hospital, Surrey, United Kingdom
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Gómez-Medina C, Capilla-Lozano M, Ballester Ferré MP, Martí-Aguado D, Crespo A, Bosca-Watts MM, Navarro Cortés P, Antón R, Pascual Moreno I, Tosca Cuquerella J, Mínguez Pérez M. Thiopurine adherence: high prevalence with low impact in UC outcomes. REVISTA ESPANOLA DE ENFERMEDADES DIGESTIVAS 2021; 114:76-82. [PMID: 33733802 DOI: 10.17235/reed.2021.7630/2020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Introduction Thiopurines are used as maintenance therapy in patients with ulcerative colitis (UC). There are contradictory results regarding the relationship between adherence to treatment and risk of relapse. Objectives To quantify and evaluate the trends in thiopurines prescription rates, and to determine the impact and risk factors of non-adherence. Methods Analytical, observational and retrospective study of UC patients, on thiopurines, included in the ENEIDA single-center registry from October 2017 to October 2019. We included adult patients under clinical remission at the beginning of the study on thiopurines maintenance treatment for at least 6 months before recruitment. Adherence was evaluated with an electronic pharmaceutical prescription system. Adherence was considered when 80% or more of the prescribed medication was dispensed at the pharmacy. Kaplan-Meier curves and a regression model were used to examine year-to-year treatment dispensation and identify factors associated to non-adherence. Results A total of 41 patients were included, of whom 71% were males with a mean age of 44 (14) and 26.8% were concomitantly managed with biological therapy. Overall, 22% were non-adherent to thiopurines. No predictive factors of non-adherence were identified. Adherence rate did not correlate with disease activity for two years follow-up (OR 1.6; 95CI =0.3-9.1). Left-sided colitis and concomitant biological treatment were related with disease relapses (p ≤0.01). Conclusion The adherence to thiopurines in UC patients is high (78%). Non-adherence is not related to clinical or pharmacological factors. Adherence rate was not associated with disease activity.
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Affiliation(s)
| | | | | | | | | | | | | | - Rosario Antón
- Medicina Digestiva, Hospital Clínico Universtiario Valencia
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9
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Zittan E, Gralnek IM, Berns MS. The New Proactive Approach and Precision Medicine in Crohn's Disease. Biomedicines 2020; 8:biomedicines8070193. [PMID: 32635316 PMCID: PMC7400127 DOI: 10.3390/biomedicines8070193] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2020] [Revised: 06/23/2020] [Accepted: 06/28/2020] [Indexed: 12/11/2022] Open
Abstract
The proactive approach to Crohn's disease (CD) management advocates moving toward algorithmic tight-control scenarios that are designed for each CD phenotype to guide remission induction, maintenance therapy, active monitoring, and multidisciplinary care to manage the complexities of each inflammatory bowel disease (IBD) patient. This requires accurate initial clinical, laboratory, radiological, endoscopic, and/or tissue diagnosis for proper phenotypic stratification of each CD patient. A substantial proportion of patients in symptomatic remission have been reported to demonstrate evidence of active disease, with elevated fecal calprotectin(FC) and C-reactive protein (CRP) levels as a hallmark for mucosal inflammation. Active mucosal inflammation, and elevated CRP and fecal calprotectin (FC) have been shown to be good predictors of clinical relapse, disease progression, and complications in IBD patients. The next frontier of treatment is personalized medicine or precision medicine to help solve the problem of IBD heterogeneity and variable responses to treatment. Personalized medicine has the potential to increase the efficacy and/or reduce potential adverse effects of treatment for each CD phenotype. However, there is currently an unmet need for better elucidation of the inflammatory biopathways and genetic signatures of each IBD phenotype, so personalized medicine can specifically target the underlying cause of the disease and provide maximal efficacy to each patient.
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Affiliation(s)
- Eran Zittan
- Ellen and Pinchas Mamber Institute of Gastroenterology and Liver Diseases, IBD unit, Emek Medical Center, Afula 1834111, Israel;
- Correspondence:
| | - Ian M. Gralnek
- Ellen and Pinchas Mamber Institute of Gastroenterology and Liver Diseases, IBD unit, Emek Medical Center, Afula 1834111, Israel;
- Rappaport Faculty of Medicine Technion-Israel Institute of Technology, Haifa 31096, Israel;
| | - Marc S. Berns
- Rappaport Faculty of Medicine Technion-Israel Institute of Technology, Haifa 31096, Israel;
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10
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Choi R, Lee MN, Kim K, Baek SY, Kim TJ, Hong SN, Kim YH, Lee SY. Effects of various genetic polymorphisms on thiopurine treatment-associated outcomes for Korean patients with Crohn's disease. Br J Clin Pharmacol 2020; 86:2302-2313. [PMID: 32372428 DOI: 10.1111/bcp.14339] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Revised: 03/31/2020] [Accepted: 04/13/2020] [Indexed: 12/23/2022] Open
Abstract
AIMS This study explores the effects of various genetic polymorphisms in candidate genes on thiopurine metabolism and toxicity in adult patients with Crohn's disease in Korea. METHODS A total of 131 adult patients with Crohn's disease receiving thiopurine treatment were included. The TPMT and NUDT15 genes and an additional 116 genetic polymorphisms (in 40 genes and 3 intergenic locations) were screened for genotyping. Among the polymorphisms screened, 91 genetic polymorphisms (in 34 genes and 3 intergenic locations) in addition to TPMT and NUDT15 genotypes were included for statistical analyses to investigate their effects on thiopurine metabolites and adverse outcomes (leukopenia, hepatotoxicity, gastrointestinal intolerance, skin rash and alopecia). RESULTS The median duration of thiopurine treatment was 47.0 months (range 6.0-153.4 months). Patient sex, maintenance dose of thiopurine, and use of anti-tumour necrosis factor agents were associated with thiopurine metabolite concentrations (P < .05). In the univariate analysis, the TPMT genotype was associated with 6-thioguanine level (P < .05), although the significance of this did not remain in multivariate analysis. Genetic polymorphisms in the ATIC (rs3821353 and rs16853834), IMPDH2 (rs11706052) and ITPA (rs6139036) genes were associated with thiopurine metabolism (P < .05). Genetic polymorphisms in the ABCC5 (rs8180093) and NUDT15 genotypes were associated with leukopenia (P < .05). CONCLUSION The results of this study may help clinicians to understand the effects of other various polymorphisms in addition to TPMT and NUDP15 in thiopurine metabolism for management of Crohn's disease patients.
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Affiliation(s)
- Rihwa Choi
- Department of Laboratory Medicine and Genetics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea.,Department of Laboratory Medicine, Green Cross Laboratories, Yongin, Gyeonggi, Republic of Korea
| | - Mi-Na Lee
- Department of Laboratory Medicine, Green Cross Laboratories, Yongin, Gyeonggi, Republic of Korea
| | - Kyunga Kim
- Statistics and Data Center, Research Institute for Future Medicine, Samsung Medical Center, Seoul, Republic of Korea
| | - Sun-Young Baek
- Statistics and Data Center, Research Institute for Future Medicine, Samsung Medical Center, Seoul, Republic of Korea
| | - Tae Jun Kim
- Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Sung Noh Hong
- Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Young-Ho Kim
- Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Soo-Youn Lee
- Department of Laboratory Medicine and Genetics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea.,Department of Clinical Pharmacology and Therapeutics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
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11
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Abstract
Introduction: The management of patients with ulcerative colitis (UC) has evolved over the past few decades. While aminosalicylates remain the mainstay of induction and maintenance therapy in patients with mild-to-moderate UC, the advent of biologic agents and novel oral small molecules has substantively changed the treatment landscape for patients with moderate-to-severe disease and confounded the role of traditional immunomodulators (IMMs) such as thiopurines and methotrexate in the UC management algorithm.Areas covered: We summarize the mechanism of action of thiopurines and methotrexate, identify clinical parameters for their use, and appraise the evidence supporting the efficacy and safety of IMMs in UC as both monotherapy and in combination with other therapies, emphasizing on prospective, controlled data.Expert opinion: With the advent of several classes of highly effective treatments for UC, emergence of data demonstrating no benefit of IMMs over placebo, and concerns about the relative safety profile of long-term IMM exposure, we propose that the role of thiopurines or methotrexate be restricted to patients with milder disease failing to maintain corticosteroid-free remission on aminosalicylates alone or in combination therapy with tumor necrosis factor antagonists in patients with moderate-to-severe UC.
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Affiliation(s)
- Tarun Chhibba
- Department of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Christopher Ma
- Division of Gastroenterology & Hepatology, University of Calgary, Calgary, Alberta, Canada.,Department of Community Health Sciences, University of Calgary, Calgary, Alberta, Canada.,Robarts Clinical Trials, Inc., London, Ontario, Canada
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12
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Hradsky O, Potuznikova K, Siroka J, Lerchova T, Urbanek L, Mihal V, Spenerova M, Velganova-Veghova M, Karaskova E, Bronsky J. Prediction of Thiopurine Metabolite Levels Based on Haematological and Biochemical Parameters. J Pediatr Gastroenterol Nutr 2019; 69:e105-e110. [PMID: 31568041 DOI: 10.1097/mpg.0000000000002436] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
OBJECTIVES Therapeutic drug monitoring of thiopurine erythrocyte levels is not available in all centers and it usually requires quite a long time to obtain the results. The aims of this study were to build a model predicting low levels of 6-thioguanine and 6-methylmercaptopurine in pediatric inflammatory bowel disease (IBD) patients and to build a model to predict nonadherence in patients treated with azathioprine (AZA). METHODS The study consisted of 332 observations in 88 pediatric IBD patients. Low AZA dosing was defined as 6-thioguanine levels <125 pmol/8 × 10 erythrocytes and 6-methylmercaptopurine levels <5700 pmol/8 × 10 erythrocytes. Nonadherence was defined as undetectable levels of 6-thioguanine and 6-methylmercaptopurine <240 pmol/8 × 10 erythrocytes. Data were divided into training and testing part. To construct the model predicting low 6-thioguanine levels, nonadherence, and the level of 6-thioguanine, the modification of random forest method with cross-validation and resampling was used. RESULTS The final models predicting low 6-thioguanine levels and nonadherence had area under the curve, 0.87 and 0.94; sensitivity, 0.81 and 0.82; specificity, 0.80 and 86; and distance, 0.31 and 0.21, respectively, when applied on the testing part of the dataset. When the final model for prediction of 6-thioguanine values was applied on testing dataset, a root-mean-square error of 110 was obtained. CONCLUSIONS Using easily obtained laboratory parameters, we constructed a model with sufficient accuracy to predict patients with low 6-thioguanine levels and a model for prediction of AZA treatment nonadherence (web applications: https://hradskyo.shinyapps.io/6TG_prediction/ and https://hradskyo.shinyapps.io/Non_adherence/).
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Affiliation(s)
- Ondrej Hradsky
- Department of Pediatrics, 2nd Faculty of Medicine, Charles University in Prague and Motol University Hospital, Prague
| | - Kristyna Potuznikova
- Department of Pediatrics, 2nd Faculty of Medicine, Charles University in Prague and Motol University Hospital, Prague
| | - Jitka Siroka
- Laboratory of Growth Regulators, Palacky University Olomouc and Institute of Experimental Botany AS CR, Olomouc
| | - Tereza Lerchova
- Department of Pediatrics, 2nd Faculty of Medicine, Charles University in Prague and Motol University Hospital, Prague
| | - Lubor Urbanek
- Laboratory of Growth Regulators, Palacky University Olomouc and Institute of Experimental Botany AS CR, Olomouc
| | - Vladimir Mihal
- Department of Pediatrics, Faculty of Medicine and Dentistry, Palacky University and University Hospital, Olomouc, Czech Republic
| | - Michaela Spenerova
- Department of Pediatrics, Faculty of Medicine and Dentistry, Palacky University and University Hospital, Olomouc, Czech Republic
| | - Maria Velganova-Veghova
- Department of Pediatrics, Faculty of Medicine and Dentistry, Palacky University and University Hospital, Olomouc, Czech Republic
| | - Eva Karaskova
- Department of Pediatrics, Faculty of Medicine and Dentistry, Palacky University and University Hospital, Olomouc, Czech Republic
| | - Jiri Bronsky
- Department of Pediatrics, 2nd Faculty of Medicine, Charles University in Prague and Motol University Hospital, Prague
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13
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Dhyani M, Joshi N, Bemelman WA, Gee MS, Yajnik V, D’Hoore A, Traverso G, Donowitz M, Mostoslavsky G, Lu TK, Lineberry N, Niessen HG, Peer D, Braun J, Delaney CP, Dubinsky MC, Guillory AN, Pereira M, Shtraizent N, Honig G, Polk DB, Hurtado-Lorenzo A, Karp JM, Michelassi F. Challenges in IBD Research: Novel Technologies. Inflamm Bowel Dis 2019; 25:S24-S30. [PMID: 31095703 PMCID: PMC6787667 DOI: 10.1093/ibd/izz077] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/29/2019] [Indexed: 12/15/2022]
Abstract
Novel technologies is part of five focus areas of the Challenges in IBD research document, which also includes preclinical human IBD mechanisms, environmental triggers, precision medicine and pragmatic clinical research. The Challenges in IBD research document provides a comprehensive overview of current gaps in inflammatory bowel diseases (IBD) research and delivers actionable approaches to address them. It is the result of a multidisciplinary input from scientists, clinicians, patients, and funders, and represents a valuable resource for patient centric research prioritization. In particular, the novel technologies section is focused on prioritizing unmet clinical needs in IBD that will benefit from novel technologies applied to: 1) non-invasive detection and monitoring of active inflammation and assessment of treatment response; 2) mucosal targeted drug delivery systems; and 3) prevention of post-operative septic complications and treatment of fistulizing complications. Proposed approaches include development of multiparametric imaging modalities and biosensors, to enable non invasive or minimally invasive detection of pro-inflammatory signals to monitor disease activity and treatment responses. Additionally, technologies for local drug delivery to control unremitting disease and increase treatment efficacy while decreasing systemic exposure are also proposed. Finally, research on biopolymers and other sealant technologies to promote post-surgical healing; and devices to control anastomotic leakage and prevent post-surgical complications and recurrences are also needed.
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Affiliation(s)
- Manish Dhyani
- Lahey Hospital & Medical Center, Burlington, Massachusetts
| | - Nitin Joshi
- Brigham and Women’s Hospital, Boston, Massachusetts
| | | | - Michael S Gee
- Massachusetts General Hospital, Boston, Massachusetts
| | - Vijay Yajnik
- Takeda Pharmaceutical Company, Boston, Massachusetts
| | - André D’Hoore
- University Hospital Gasthuisberg and University of Leuven, Leuven, Belgium
| | - Giovanni Traverso
- Brigham and Women’s Hospital, Harvard Medical School and Massachusetts Institute of Technology, Boston, Massachusetts
| | - Mark Donowitz
- Johns Hopkins University School of Medicine, Baltimore, Maryland
| | | | - Timothy K Lu
- Massachusetts Institute of Technology, Cambridge, Massachusetts
| | | | - Heiko G Niessen
- Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach, Germany
| | - Dan Peer
- School of Molecular Cell Biology and Biotechnology, Tel Aviv University, Tel Aviv, Israel
| | - Jonathan Braun
- Inflammatory Bowel and Immunobiology Research Institute, Cedars-Sinai, Los Angeles, California
| | | | | | | | | | | | - Gerard Honig
- Crohn’s & Colitis Foundation, New York, New York
| | - David Brent Polk
- Department of Biochemistry and Molecular Biology, University of Southern California,Department of Pediatrics, Children’s Hospital Los Angeles, Los Angeles, California
| | - Andrés Hurtado-Lorenzo
- Crohn’s & Colitis Foundation, New York, New York,Address correspondence to: Andrés Hurtado-Lorenzo, PhD, 733 3rd Ave Suite 510, New York, NY USA 10017 ()
| | - Jeffrey M Karp
- Department of Medicine, Brigham and Women’s Hospital, Harvard Medical School, Harvard-MIT Division of Health Sciences and Technology, Broad Institute and Harvard Stem Cell Institute, Boston, Massachusetts
| | - Fabrizio Michelassi
- New York-Presbyterian Hospital and Weill Cornell School of Medicine, New York, New York
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14
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Sparrow MP, Melmed GY, Devlin S, Kozuch P, Raffals L, Loftus Jr EV, Rubin DT, Spiegel B, Baidoo L, Bressler B, Cheifetz A, Irving P, Jones J, Kaplan GG, Velayos F, Siegel CA. De‐escalating medical therapy in Crohn’s disease patients who are in deep remission: A RAND appropriateness panel. ACTA ACUST UNITED AC 2019. [DOI: 10.1002/ygh2.337] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Miles P. Sparrow
- The BRIDGe Group
- The Alfred Hospital Melbourne Victoria Australia
| | - Gil Y. Melmed
- The BRIDGe Group
- Cedars‐Sinai Medical Center Los Angeles California
| | - Shane Devlin
- The BRIDGe Group
- University of Calgary Calgary Alberta Canada
| | - Patricia Kozuch
- The BRIDGe Group
- Jefferson University Philadelphia Pennsylvania
| | | | | | | | | | | | - Brian Bressler
- The BRIDGe Group
- University of British Columbia Vancouver British Columbia Canada
| | - Adam Cheifetz
- The BRIDGe Group
- Beth Israel Deaconess Medical Center Boston Massachusetts
| | - Peter Irving
- The BRIDGe Group
- Guy's and St. Thomas' Hospitals London UK
| | - Jennifer Jones
- The BRIDGe Group
- Dalhousie University Halifax Nova Scotia Canada
| | | | | | - Corey A. Siegel
- The BRIDGe Group
- Dartmouth‐Hitchcock IBD Center Lebanon New Hampshire
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15
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Frick S, Müller D, Kullak-Ublick GA, Jetter A. Do clinical and laboratory parameters predict thiopurine metabolism and clinical outcome in patients with inflammatory bowel diseases? Eur J Clin Pharmacol 2019; 75:335-342. [PMID: 30610277 DOI: 10.1007/s00228-018-02616-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2018] [Accepted: 12/18/2018] [Indexed: 11/28/2022]
Abstract
PURPOSE The thiopurines azathioprine and 6-mercaptopurine are frequently used for remission maintenance in patients with inflammatory bowel diseases. However, there are therapy failures, and it is unclear whether clinical and laboratory parameters can be used to predict thiopurine metabolite concentrations (as a surrogate for adequate remission maintenance therapy) and clinical outcome in these patients. METHODS In this retrospective analysis of clinical routine patient data, multivariate statistical models based on Linear Mixed Models regression and Generalized Estimating Equations logistic regression were developed. The adequacy of the models was assessed using Pearson's correlation and a receiver operating characteristic curve. RESULTS This study included 273 patients and 1158 thiopurine metabolite measurements as well as routine laboratory and clinical data. In the statistical models, thiopurine metabolite concentrations and the odds of non-remission based on different clinical and laboratory parameters were computed. Correlation (r2) between predicted and measured thiopurine metabolites were 0.40 (p < 0.001) for 6-thioguanine nucleotides and 0.53 (p < 0.001) for 6-methyl-mercaptopurine nucleotides, respectively. The model for remission classified data sets in remission and non-remission with a sensitivity of 63% and a specificity of 73%. The area under the receiver operating characteristic curve of the model was 0.72. CONCLUSIONS Although the models are not yet accurate enough to be used in clinical routine, model-based prediction of thiopurine metabolite concentrations and of outcome is feasible. Until more accurate models are developed and validated, traditional therapeutic drug monitoring of thiopurine metabolites in patients with inflammatory bowel diseases under thiopurine therapy stays the best tool to individualize therapy.
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Affiliation(s)
- Sven Frick
- Department of Clinical Pharmacology and Toxicology, University Hospital Zurich, University of Zurich, Rämistrasse 100, CH-8091, Zürich, Switzerland
| | - Daniel Müller
- Institute of Clinical Chemistry, University Hospital Zurich, University of Zurich, Zurich, Switzerland
| | - Gerd A Kullak-Ublick
- Department of Clinical Pharmacology and Toxicology, University Hospital Zurich, University of Zurich, Rämistrasse 100, CH-8091, Zürich, Switzerland
| | - Alexander Jetter
- Department of Clinical Pharmacology and Toxicology, University Hospital Zurich, University of Zurich, Rämistrasse 100, CH-8091, Zürich, Switzerland.
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16
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Fecal calprotectin is significantly linked to azathioprine metabolite concentrations in Crohn's disease. Eur J Gastroenterol Hepatol 2019; 31:99-108. [PMID: 30212402 DOI: 10.1097/meg.0000000000001262] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
BACKGROUND The value of therapeutic drug monitoring during azathioprine (AZA) therapy with respect to clinical outcomes has been convincingly demonstrated in recent meta-analyses. However, the association between AZA metabolites and the mucosal state in inflammatory bowel disease is largely unclear. AIMS We investigated the association between AZA's active metabolite 6-thioguanine nucleotides (6-TGN) and fecal calprotectin (FC) as a well-validated surrogate marker of mucosal inflammation in patients with Crohn's disease (CD) on AZA monotherapy. PATIENTS AND METHODS Of 443 6-TGN measurements, 140 values from 88 patients with CD on AZA monotherapy visiting the inflammatory bowel disease outpatient clinic between 2009 and 2016 were retrospectively analyzed. In a subcohort with serial 6-TGN measurements, longitudinal FC measurements in patients with versus without intervention (dose increase, allopurinol, and education) were assessed. RESULTS In patients with 6-TGN concentrations within a predefined range (250-450 pmol/8×10 red blood cells), FC was significantly lower (median: 119.5 vs. 327.2 mg/kg, P=0.003), and hemoglobin as well as serum protein concentrations were significantly higher than in patients with 6-TGN outside of this range. C-reactive protein and transferrin saturation were not different. In the longitudinal cohort, 6-TGN increased in the intervention group, but only a minority reached the defined range; no significant change in FC was observed. CONCLUSION This study is the first to show that in patients with CD receiving AZA monotherapy, 6-TGN concentrations within a defined range (250-450 pmol/8×10 red blood cells) are associated with significantly lower FC. A treat-to-target concept directed by 6-TGN to reach mucosal healing may thus be a promising approach (DRKS00013246).
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17
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Álvarez JP, Coloma R, Leiva A, Berry M, Urrutia L, Yañez S, Galecio J, Ramos G, Cárcamo M, Fernández A, Guerrero M. Efecto de ketamina intraoperatoria sobre consumo de morfina durante 24 horas postoperatorias de pacientes obesos sometidos a gastrectomía en manga por videolaparoscopía. Ensayo Clínico Controlado Aleatorizado. REVISTA MÉDICA CLÍNICA LAS CONDES 2018. [DOI: 10.1016/j.rmclc.2018.10.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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18
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Ibáñez P, Quera R, Lubascher J, Figueroa C, Pizarro G, Kronberg U, Flores L, Simian D. Algoritmos de tratamiento de la enfermedad de Crohn desde una experiencia local. REVISTA MÉDICA CLÍNICA LAS CONDES 2018. [DOI: 10.1016/j.rmclc.2018.07.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
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19
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Lim SZ, Chua EW. Revisiting the Role of Thiopurines in Inflammatory Bowel Disease Through Pharmacogenomics and Use of Novel Methods for Therapeutic Drug Monitoring. Front Pharmacol 2018; 9:1107. [PMID: 30349479 PMCID: PMC6186994 DOI: 10.3389/fphar.2018.01107] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2018] [Accepted: 09/10/2018] [Indexed: 12/12/2022] Open
Abstract
Azathioprine and 6-mercaptopurine, often referred to as thiopurine compounds, are commonly used in the management of inflammatory bowel disease. However, patients receiving these drugs are prone to developing adverse drug reactions or therapeutic resistance. Achieving predefined levels of two major thiopurine metabolites, 6-thioguanine nucleotides and 6-methylmercaptopurine, is a long-standing clinical practice in ensuring therapeutic efficacy; however, their correlation with treatment response is sometimes unclear. Various genetic markers have also been used to aid the identification of patients who are thiopurine-sensitive or refractory. The recent discovery of novel Asian-specific DNA variants, namely those in the NUDT15 gene, and their link to thiopurine toxicity, have led clinicians and scientists to revisit the utility of Caucasian biomarkers for Asian individuals with inflammatory bowel disease. In this review, we explore the limitations associated with the current methods used for therapeutic monitoring of thiopurine metabolites and how the recent discovery of ethnicity-specific genetic markers can complement thiopurine metabolites measurement in formulating a strategy for more accurate prediction of thiopurine response. We also discuss the challenges in thiopurine therapy, alongside the current strategies used in patients with reduced thiopurine response. The review is concluded with suggestions for future work aiming at using a more comprehensive approach to optimize the efficacy of thiopurine compounds in inflammatory bowel disease.
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Affiliation(s)
| | - Eng Wee Chua
- Faculty of Pharmacy, Universiti Kebangsaan Malaysia, Kuala Lumpur, Malaysia
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20
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Pecher D, Dokupilová S, Zelinková Z, Peppelenbosch M, Lučeničová J, Mikušová V, Mikuš P. Analytical and Sample Preparation Protocol for Therapeutic Drug Monitoring of 12 Thiopurine Metabolites Related to Clinical Treatment of Inflammatory Bowel Disease. Molecules 2018; 23:E1744. [PMID: 30018218 PMCID: PMC6100499 DOI: 10.3390/molecules23071744] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2018] [Revised: 07/13/2018] [Accepted: 07/15/2018] [Indexed: 11/17/2022] Open
Abstract
Thiopurines (TP) represent an important therapeutic tool for the treatment of inflammatory bowel diseases (IBD) in the current situation of rising incidence and health care costs. The results of multiple clinical studies aimed at finding correlations between levels of TP metabolites and response of IBD patients to the treatment are, however, often controversial due to variability in analytical and sample preparation procedures among these studies. In this work, therefore, an updated analytical and sample preparation procedure for therapeutic drug monitoring (TDM) of TP metabolites in blood samples obtained from patients with IBD was proposed to establish a unified protocol. An advanced analytical method based on ion-exchange liquid chromatography hyphenated with tandem mass spectrometry (IEC-ESI-MS/MS) was used for the determination of the profiles of 12 individual TP metabolites in the particular steps of sample preparation procedure including blood collection, red blood cells (RBC) isolation, lysis, and storage. Favorable performance parameters of the IEC-ESI-MS/MS method (LLOQs 1⁻10 nmol/L, accuracy 95⁻105%, intra-day and inter-day precision < 10%, selectivity demonstrated via no sample matrix interferences) and acceptable stability (peak area fluctuations < 15%) of clinical samples under the proposed sample preparation conditions {(i) EDTA anticoagulant tube for the blood collection; (ii) 4 °C and 4 h between the sample collection and RBC isolation; (iii) phosphate-buffered saline for RBC washing and re-suspendation; (iv) -20 °C for RBC lysis and short-term storage; (v) 50 mmol/L phosphate buffer, pH 7.4, 10 mmol/L DTT as a stabilizing medium for TPN in RBC lysates} demonstrated the suitability of such protocol for a well-defined and reliable routine use in studies on thiopurines TDM.
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Affiliation(s)
- Daniel Pecher
- Department of Pharmaceutical Analysis and Nuclear Pharmacy, Faculty of Pharmacy, Comenius University in Bratislava, Odbojárov 10, SK-832 32 Bratislava, Slovakia.
- Toxicological and Antidoping Center, Faculty of Pharmacy, Comenius University in Bratislava, Odbojárov 10, SK-832 32 Bratislava, Slovakia.
| | - Svetlana Dokupilová
- Department of Pharmaceutical Analysis and Nuclear Pharmacy, Faculty of Pharmacy, Comenius University in Bratislava, Odbojárov 10, SK-832 32 Bratislava, Slovakia.
- Toxicological and Antidoping Center, Faculty of Pharmacy, Comenius University in Bratislava, Odbojárov 10, SK-832 32 Bratislava, Slovakia.
| | - Zuzana Zelinková
- Department of Gastroenterology, St Michael's Hospital, Satinského 1, SK-811 08 Bratislava, Slovakia.
| | - Maikel Peppelenbosch
- Gastrolab, Erasmus Medical Center, Wytemaweg 80, 3015 CN Rotterdam, The Netherlands.
| | - Jana Lučeničová
- Department of Biochemistry & Hematology, St Michael's Hospital, Satinského 1, SK-811 08 Bratislava, Slovakia.
| | - Veronika Mikušová
- Department of Galenic Pharmacy, Faculty of Pharmacy, Comenius University in Bratislava, Odbojárov 10, SK-832 32 Bratislava, Slovakia.
| | - Peter Mikuš
- Department of Pharmaceutical Analysis and Nuclear Pharmacy, Faculty of Pharmacy, Comenius University in Bratislava, Odbojárov 10, SK-832 32 Bratislava, Slovakia.
- Toxicological and Antidoping Center, Faculty of Pharmacy, Comenius University in Bratislava, Odbojárov 10, SK-832 32 Bratislava, Slovakia.
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21
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Analytical Pitfalls of Therapeutic Drug Monitoring of Thiopurines in Patients With Inflammatory Bowel Disease. Ther Drug Monit 2018; 39:584-588. [PMID: 29040228 PMCID: PMC5690305 DOI: 10.1097/ftd.0000000000000455] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The use of thiopurines in the treatment of inflammatory bowel disease (IBD) can be optimized by the application of therapeutic drug monitoring. In this procedure, 6-thioguanine nucleotides (6-TGN) and 6-methylmercaptopurine (6-MMP) metabolites are monitored and related to therapeutic response and adverse events, respectively. Therapeutic drug monitoring of thiopurines, however, is hampered by several analytical limitations resulting in an impaired translation of metabolite levels to clinical outcome in IBD. Thiopurine metabolism is cell specific and requires nucleated cells and particular enzymes for 6-TGN formation. In the current therapeutic drug monitoring, metabolite levels are assessed in erythrocytes, whereas leukocytes are considered the main target cells of these drugs. Furthermore, currently used methods do not distinguish between active nucleotides and their unwanted residual products. Last, there is a lack of a standardized laboratorial procedure for metabolite assessment regarding the substantial instability of erythrocyte 6-TGN. To improve thiopurine therapy in patients with IBD, it is necessary to understand these limitations and recognize the general misconceptions in this procedure.
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22
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Schulze H, Esters P, Hartmann F, Stein J, Christ C, Zorn M, Dignass A. A prospective cohort study to assess the relevance of vedolizumab drug level monitoring in IBD patients. Scand J Gastroenterol 2018; 53:670-676. [PMID: 29560811 DOI: 10.1080/00365521.2018.1452974] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
BACKGROUND Vedolizumab (VDZ) drug monitoring strategies in inflammatory bowel disease (IBD) patients have not been systematically investigated so far. We evaluated the correlation between VDZ trough levels (VTL) and the treatment response in IBD. METHODS Fifty-one patients with active IBD on or starting a therapy with VDZ were enrolled in this prospective and observational single centre study. Disease activity indices, blood tests, and anthropometric parameters were assessed over a time period of 6 months. One hundred and fifty-five VDZ serum trough levels were measured directly before the next scheduled application using liquid chromatography mass spectrometry (LC-MS/MS). RESULTS VDZ treatment was found to be clinically effective (Harvey Bradshaw Index (HBI) dropping from 10 to 5.5 points (p < .0005) in Crohn's disease (CD) patients; partial Mayo score (pMS) from 4.4 to 2.1 points (p < .0005) in ulcerative colitis patients (UC). CRP levels tended to decrease and haemoglobin levels to increase under VDZ therapy. CD patients with a serum CRP level lower than 5 mg/l exhibited significantly higher VTL than those with elevated CRP levels (34.9 versus 21.7 µg/ml, p = .00153). UC patients with haemoglobin levels higher 12 g/dl at the time of VTL measurement had significantly higher VTL compared to patients with lower haemoglobin levels (35.4 versus 15.6 µg/ml, p < .0005). CONCLUSIONS Our data suggest a significant correlation between VTL and response to therapy in IBD patients (higher VTL associated with better response).
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Affiliation(s)
- Hermann Schulze
- a Department of Medicine I , Agaplesion Markus Hospital , Frankfurt , Germany
| | - Philip Esters
- a Department of Medicine I , Agaplesion Markus Hospital , Frankfurt , Germany
| | - Franz Hartmann
- a Department of Medicine I , Agaplesion Markus Hospital , Frankfurt , Germany
| | - Juergen Stein
- b Interdisziplinäres Crohn Colitis Centrum , Frankfurt , Germany
| | | | | | - Axel Dignass
- a Department of Medicine I , Agaplesion Markus Hospital , Frankfurt , Germany
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23
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Patients' beliefs about medicine are associated with early thiopurine discontinuation in patients with inflammatory bowel diseases. Eur J Gastroenterol Hepatol 2018; 30:167-173. [PMID: 29120908 PMCID: PMC5757657 DOI: 10.1097/meg.0000000000001025] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
BACKGROUND Patients' beliefs about medicine may either reflect the necessity for treatment or concerns regarding the treatment. We explored the extent to which these beliefs have an effect on thiopurine metabolite levels and premature discontinuation in patients with inflammatory bowel disease (IBD). PATIENTS AND METHODS Patients enrolled in the 'Thiopurine response Optimization by Pharmacogenetic testing in Inflammatory Bowel Disease Clinics' (TOPIC) trial were asked to complete the Beliefs about Medicine Questionnaire (BMQ) 4 weeks after thiopurine initiation. The BMQ measures perceptions about treatment necessity and concerns. On the basis of the necessity and concern scores, patients can be categorized as accepting, ambivalent, indifferent, or skeptical. The thiopurine discontinuation rates for these belief subgroups were compared by Kaplan-Meier curves. Furthermore, clinical response and metabolite levels were compared between the belief subgroups. RESULTS A total of 767 patients with IBD started thiopurine treatment, of whom 576 (75%) completed the BMQ. Patients could be classified as accepting (34%), indifferent (17%), ambivalent (34%), or skeptical (15%). Compared with patients in the accepting group (discontinuation rate 22%), patients with an indifferent (35%; P=0.02), ambivalent (37%; P<0.01), or skeptical belief (54%; P<0.01) had higher thiopurine discontinuation rates. No differences were observed in the steady-state thiopurine metabolite levels between the different belief subgroups. CONCLUSION Patients with a low perceived treatment necessity or high concerns toward IBD treatment were more likely to discontinue thiopurine treatment prematurely. Extra attention toward these patients might prevent premature discontinuation.
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24
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Guillotin V, Galli G, Viallard JF. [Usefulness of thiopurine methyltransferase polymorphism study and metabolites measurement for patients treated by azathioprine]. Rev Med Interne 2018; 39:421-426. [PMID: 29370945 DOI: 10.1016/j.revmed.2017.12.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2017] [Revised: 12/18/2017] [Accepted: 12/28/2017] [Indexed: 11/18/2022]
Abstract
Azathioprine is widely used in internal medicine and frequently implicated in occurrence of adverse events. Among these adverse events the bone marrow suppression, a dose-related one, is the most serious because of is potential morbidity and mortality. Severe myelosuppression, associated with abnormal AZA metabolism, is linked to the thiopurine methyltransferase (TPMT) genetic polymorphism that results in a high variability of its activity with 89% of patients with a normal activity, 11% with an intermediate activity, and 0.3% with very low activity leading to a very high risk of bonne marrow suppression. TPMT status can be assessed prior to AZA treatment by measuring enzyme activity or genotyping techniques to identify patients for which the standard dose is not advisable. Furthermore, azathioprine metabolites monitoring is helpful for the follow up of patients, especially in therapeutic failure, to distinguish non-compliant patients from under-dosed, "shunters" or resistant patients.
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Affiliation(s)
- V Guillotin
- Laboratoire d'immunologie de l'hôpital Pellegrin, place Amélié-Raba-Léon, 33000 Bordeaux, France.
| | - G Galli
- Service de médecine interne et immunologie clinique, Hôpital Saint-André, rue Jean-Burguet, 33000 Bordeaux, France
| | - J-F Viallard
- Service de médecine interne, hôpital du Haut-Lévêque, avenue Magellan, 33604 Pessac, France
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25
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Lee JH, Kim TJ, Kim ER, Hong SN, Chang DK, Choi LH, Woo HI, Lee SY, Kim YH. Measurements of 6-thioguanine nucleotide levels with TPMT and NUDT15 genotyping in patients with Crohn's disease. PLoS One 2017; 12:e0188925. [PMID: 29206869 PMCID: PMC5716599 DOI: 10.1371/journal.pone.0188925] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2017] [Accepted: 11/15/2017] [Indexed: 02/06/2023] Open
Abstract
The association between the 6-thioguanine nucleotide (6-TGN) level and clinical remission in Crohn’s disease (CD) remains controversial. Thiopurine-induced leukopenia is a life-threatening complication of CD in Asians that was recently shown to strongly correlate with NUDT15 genetic variants. This study aimed to determine the relationship between thiopurine metabolite levels and therapeutic response, and to investigate the association of NUDT15, TPMT, and thiopurine metabolites with leukopenia in patients with CD. We enrolled 165 adult patients with CD undergoing thiopurine treatment. Clinical evaluation and laboratory examinations were carried out every 2–3 months. We measured thiopurine metabolites levels and genotyped NUDT15 and TPMT. During the median 12-month observational period, 95 (67.9%) patients exhibited clinical response and 45 (32.1%) did not respond to the treatment. The median 6-TGN level was significantly higher in responders than in non-responders (P < 0.001). The odds ratio of patients with a 6-TGN level ≥230 pmol/8 × 108 red blood cells for showing a clinical response was 4.63 (95% CI 1.62–11.9). NUDT15 variant types were strongly associated with developing leukopenia. Patients with NUDT15 homozygous variant genotype developed severe early leukopenia with an average reduction of 88.2% (range, 84–94%) from the baseline white blood cell count at 4 weeks. Our findings support the role of therapeutic drug monitoring in thiopurine maintenance treatment to optimize thiopurine therapy, especially, for non-responding CD patients. Thiopurine treatment should not be recommended to patients with NUDT15 homozygous variant genotype due to severe early leukopenia.
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Affiliation(s)
- Ji Hyeon Lee
- Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Tae Jun Kim
- Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Eun Ran Kim
- Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Sung Noh Hong
- Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Dong Kyung Chang
- Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Li-Hwa Choi
- Department of Laboratory Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
- Department of Laboratory Medicine, Green Cross Laboratories, Yongin, Gyeonggi, Republic of Korea
| | - Hye In Woo
- Department of Laboratory Medicine, Samsung Changwon Hospital, Sungkyunkwan University School of Medicine, Changwon, Republic of Korea
| | - Soo-Youn Lee
- Department of Laboratory Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
- * E-mail: (YK); (SL)
| | - Young-Ho Kim
- Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
- * E-mail: (YK); (SL)
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Rac1 as a Potential Pharmacodynamic Biomarker for Thiopurine Therapy in Inflammatory Bowel Disease. Ther Drug Monit 2017; 38:621-7. [PMID: 27465973 DOI: 10.1097/ftd.0000000000000326] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
BACKGROUND Azathioprine and mercaptopurine (MP) are effective in treating patients with inflammatory bowel disease (IBD). Immunosuppressive effects of thiopurines involve T-cell apoptosis after inhibition of GTPase Ras-related C3 botulinum toxin substrate 1 (Rac1). This study aimed to assess whether expression and activity of Rac1 or phosphorylated ezrin-radixin-moesin (pERM) in patients with IBD could provide a useful biomarker for the pharmacodynamic thiopurine effect and might be related to clinical effectiveness. METHODS This was a 2-stage study: stage 1 concerned a cross-sectional cohort of patients with IBD clinically in remission and treated with (n = 10) or without stable weight-based thiopurine therapy (n = 11) and healthy controls (n = 6); stage 2 concerned a prospective study regarding IBD patients with clinically active disease who initiated MP therapy (n = 11) compared with healthy controls (n = 11). Expression and activity of Rac1 and ERM and pERM were determined. RESULTS The median Rac1 expression was statistically significantly reduced by thiopurine maintenance therapy {0.54 [interquartile range (IQR) 0.47-0.88] versus 0.80 arbitrary units [IQR 0.64-1.46]} compared with patients without immunosuppressive therapy (P = 0.042), but not Rac1 activity and pERM. In responders to MP therapy (n = 6), both median active Rac1 [93 (IQR 81-151) to 76 ng Rac1/mg protein (IQR 62-98)] and Rac1 expression [16.2 (8.8-29.4) to 1.5 arbitrary units (0.9-5.3)] decreased (P = 0.028). In nonresponders (n = 3), Rac1 expression and activity increased. CONCLUSIONS IBD patients treated with thiopurines had a lower expression of Rac1 compared with those not treated with thiopurine. Effective MP therapy led to decreasing concentrations of Rac1-GTP and Rac1 expression. Therefore, Rac1-GTP and expression of Rac1, but not phosphorylation of ERM, form potentially pharmacodynamic markers of therapeutic thiopurine effectiveness in patients with IBD.
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Estevinho MM, Afonso J, Rosa I, Lago P, Trindade E, Correia L, Dias CC, Magro F. A Systematic Review and Meta-Analysis of 6-Thioguanine Nucleotide Levels and Clinical Remission in Inflammatory Bowel Disease. J Crohns Colitis 2017; 11:1381-1392. [PMID: 28981590 DOI: 10.1093/ecco-jcc/jjx089] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
BACKGROUND AND AIMS Thiopurines are widely used in the management of inflammatory bowel diseases. However, their minimum effective dose and dose-response relationship remain undefined, and evidence about their use in clinical practice is mostly heterogeneous. This systematic review and meta-analysis aimed: i] to assess the clinical value of 6-thioguanine nucleotide thresholds; and ii] to compare mean 6-thioguanine nucleotide concentrations between patients in clinical remission vs. those with active disease. METHODS A systematic literature search was carried out using four databases. Statistical heterogeneity was assessed with the I2 statistic followed by subgroup and sensitivity analyses. Odds ratios were computed using the random-effects model. RESULTS A total of 1384 records were identified in the systematic search, of which 25 were retained for further analysis: 22 were used in the cut-off comparisons and 12 were used in the 6-thioguanine nucleotide mean differences analysis. The global odds ratio for remission in patients with 6-thioguanine nucleotide levels above the predefined thresholds was 3.95 (95% confidence interval [CI], 2.63-5.94; p < 0.001]. When considering the different thresholds individually, the odd ratios were significant for values above 235 pmol/8 × 108 and 250 pmol/8 × 108 red blood cells [2.25 and 4.71, respectively]. Mean 6-thioguanine nucleotide levels were higher among patients in clinical remission, with a pooled difference of 63.37 pmol/8 × 108 red blood cells [95% CI, 31.81-94.93; p < 0.001]. CONCLUSIONS This study reinforces the link between 6-thioguanine nucleotide levels and clinical remission in inflammatory bowel diseases, also exploring the validity of specific 6-thioguanine nucleotide thresholds to predict clinical outcomes.
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Affiliation(s)
- Maria Manuela Estevinho
- Department of Pharmacology and Therapeutics, Faculty of Medicine of the University of Porto, Porto, Portugal
| | - Joana Afonso
- Department of Pharmacology and Therapeutics, Faculty of Medicine of the University of Porto, Porto, Portugal
| | - Isadora Rosa
- Gastroenterology Department, Instituto Portugue^s de Oncologia de Lisboa, Lisboa, Portugal
| | - Paula Lago
- Gastroenterology Department, Centro Hospitalar do Porto, Porto, Portugal
| | - Eunice Trindade
- Department of Pediatrics, Centro Hospitalar São João, Porto, Portugal
| | - Luís Correia
- Department of Gastroenterology and Hepatology, Hospital de Santa Maria, University of Lisbon, Lisbon, Portugal
| | - Cláudia Camila Dias
- Department of Community Medicine, Faculty of Medicine of the University of Porto, Porto, Portugal, and Centre for Health Technology and Services Research, Porto, Portugal
| | - Fernando Magro
- Department of Pharmacology and Therapeutics, Faculty of Medicine of the University of Porto, Porto, Portugal.,Department of Gastroenterology, Faculty of Medicine, Centro Hospitalar São João, Porto, Portugal
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Rac Attack: Modulation of the Small GTPase Rac in Inflammatory Bowel Disease and Thiopurine Therapy. Mol Diagn Ther 2017; 20:551-557. [PMID: 27604084 PMCID: PMC5107185 DOI: 10.1007/s40291-016-0232-1] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The incidence and prevalence of inflammatory bowel disease (IBD) are increasing. Although the etiology of IBD is unknown, it is thought that genetically susceptible individuals display an inappropriate inflammatory response to commensal microbes, resulting in intestinal tissue damage. Key proteins involved in regulating the immune response, and thus in inflammation, are the small triphosphate-binding protein Rac and its regulatory network. Recent data suggest these proteins to be involved in (dys)regulation of the characteristic inflammatory processes in IBD. Moreover, Rac-gene variants have been identified as susceptibility risk factors for IBD, and Rac1 GTPase signaling has been shown to be strongly suppressed in non-inflamed mucosa compared with inflamed colonic mucosa in IBD. In addition, first-line immunosuppressive treatment for IBD includes thiopurine therapy, and its immunosuppressive effect is primarily ascribed to Rac1 suppression. In this review, we focus on Rac modification and its potential role in the development of IBD, Rac as the molecular therapeutic target in current thiopurine therapy, and the modulation of the Rac signal transduction pathway as a promising novel therapeutic strategy.
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Abstract
BACKGROUND There are substantial global differences in the preference for mercaptopurine (MP) or its prodrug azathioprine (AZA) as first-choice thiopurine to treat inflammatory bowel diseases. Studies comparing both agents are scarce. Our aim was to compare AZA and MP in thiopurine-naive patients with inflammatory bowel disease for the frequency of side effects and efficacy. METHODS Post hoc analysis of the "Thiopurine response Optimization by Pharmacogenetic testing in Inflammatory bowel disease Clinics" (TOPIC) trial, in which thiopurine-naive patients with inflammatory bowel disease with an indication for a thiopurine were randomized for a genotype-based dose versus standard of care. For this study, Cox proportional hazard ratios (HRs) were calculated to compare AZA and MP for discontinuation rates within 5 months, incidence of hepatotoxicity, leukopenia, and gastrointestinal side effects. Treatment efficacy was compared by logistic regression. RESULTS Patient characteristics were similar for patients treated with AZA (n = 494, 64.4%) and MP (n = 273, 35.6%), yet patients with MP were relatively higher dosed compared with those on AZA. Discontinuation rates within 5 months were not different, 39.3% (AZA) and 38.1% (MP), HR 0.92 (95% confidence interval, 0.72-1.17; P = 0.50); however, patients on MP were more often subjected to dose reductions (30% versus 14%, P < 0.01). Higher rates of hepatotoxicity, HR 1.93 (95% confidence interval, 1.35-2.76; P < 0.01) and leukopenia, HR 2.55 (95% confidence interval, 1.51-4.30; P < 0.01) were observed with MP, which annulled in a secondary analysis with adjustment for the higher dose and metabolite levels. CONCLUSIONS Patients treated with MP were relatively higher dosed, which resulted in more dose-dependent side effects and a higher rate of dose reductions.
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Vetter M, Neurath MF. Emerging oral targeted therapies in inflammatory bowel diseases: opportunities and challenges. Therap Adv Gastroenterol 2017; 10:773-790. [PMID: 29051788 PMCID: PMC5638182 DOI: 10.1177/1756283x17727388] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/30/2017] [Accepted: 07/31/2017] [Indexed: 02/04/2023] Open
Abstract
To improve quality of life and prevent long-term risks in patients with inflammatory bowel diseases (IBDs: Crohn's disease, ulcerative colitis), it is essential to suppress inflammatory activity adequately. However, corticosteroids are only suitable for therapy of acute flares and the evidence for positive effects of immunosuppressive substances like azathioprine or 6-mercapropurine is mainly limited to maintenance of remission. In addition, only subgroups of patients benefit from biologicals targeting tumour necrosis factor α or α4β7 integrins. In summary, until now the disease activity is not sufficiently controlled in a relevant fraction of the patients with IBD. Thus, there is an urge for the development of new substances in the therapy of ulcerative colitis and Crohn's disease. Fortunately, new oral and parenteral substances are in the pipeline. This review will focus on oral substances, which have already passed phase II studies successfully at this stage. In this article, we summarize data regarding AJM300, phosphatidylcholine (LT-02), mongersen, ozanimod, filgotinib and tofacitinib. AJM300 and ozanimod were tested in patients with ulcerative colitis and target lymphocyte trafficking through inhibition of the α subunit of integrin, respectively binding to the sphingosine-1-phosphate receptor (subtypes 1 and 5) on lymphocytes. Mongersen was utilized in patients with Crohn's disease and accelerates the degradation of SMAD7 mRNA, which consequently strengthens the mainly anti-inflammatory signalling pathway of transforming growth factor β1. Various Janus kinase (JAK) inhibitors were developed, which inhibit the intracellular signalling pathway of cytokines. For example, the JAK1 blocker filgotinib was tested in Crohn's disease, whereas the JAK1/3 inhibitor tofacitinib was tested in clinical trials for both Crohn's disease and ulcerative colitis. A different therapeutic approach is the substitution of phosphatidylcholine (LT-02), which might recover the colonic mucus. Taken together, clinical trials with these new agents have opened avenues for further clinical studies and it can be expected that at least some of these agents will be finally approved for clinical therapy.
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Affiliation(s)
- Marcel Vetter
- Department of Medicine 1, Friedrich-Alexander-Universität Erlangen-Nürnberg, Germany
| | - Markus F. Neurath
- Department of Medicine 1, Friedrich-Alexander-Universität Erlangen-Nürnberg, Ulmenweg 18, Erlangen, 91054, Germany
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Garritsen FM, van der Schaft J, Bruijnzeel-Koomen CAF, van Schaik RH, de Graaf M, van den Broek MPH, de Bruin-Weller MS. Thiopurine metabolite levels in patients with atopic dermatitis and/or chronic hand/foot eczema treated with azathioprine. J DERMATOL TREAT 2017; 29:375-382. [PMID: 28914560 DOI: 10.1080/09546634.2017.1373738] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
BACKGROUND Azathioprine is frequently used in severe eczema. It is converted in the liver into active metabolites, including 6-thioguanine nucleotide (6-TGN) and methylated 6-methylmercaptopurine (6-MMP). In the past, the therapeutic potential of azathioprine may have not been fully utilized. Recent investigations on inflammatory bowel disease have led to a better understanding of azathioprine metabolism and optimizing treatment. OBJECTIVE To investigate whether measuring thiopurine metabolites in circulation can improve the effectiveness and safety of azathioprine treatment in patients with atopic dermatitis and/or chronic hand/foot eczema. METHODS Azathioprine metabolite levels were measured in eczema patients during maintenance treatment (Part I) and dose escalation (Part II). Clinical effectiveness, hepatotoxicity, and bone marrow suppression were analyzed and TPMT genotype was assessed. RESULTS A wide variation in metabolite levels in all dose groups was observed. In Part I (32 patients), there were no significant differences in 6-TGN levels between clinical responders and non-responders (p = .806). No hepatoxicity or myelotoxicity was observed. In Part II, all 6-TGN and 6-MMP levels increased during dose escalation. Hypermethylation was observed in 2/8 patients. CONCLUSION For individual eczema patients treated with azathioprine, routinely measuring 6-TGN and 6-MMP can be helpful in optimizing azathioprine dose, improving clinical effectiveness, and preventing side effects.
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Affiliation(s)
- F M Garritsen
- a Department of Dermatology , University Medical Center Utrecht , Utrecht , The Netherlands
| | - J van der Schaft
- a Department of Dermatology , University Medical Center Utrecht , Utrecht , The Netherlands
| | | | - R H van Schaik
- b Department of Clinical Chemistry , Erasmus University Medical Center Rotterdam , Rotterdam , The Netherlands.,c Laboratory for Clinical Chemistry and Hematology (LKCH) , University Medical Center Utrecht , Utrecht , The Netherlands
| | - M de Graaf
- a Department of Dermatology , University Medical Center Utrecht , Utrecht , The Netherlands
| | - M P H van den Broek
- d Department of Clinical Pharmacy , University Medical Center Utrecht , Utrecht , The Netherlands.,e Department of Clinical Pharmacy , St Antonius Hospital , Nieuwegein , The Netherlands
| | - M S de Bruin-Weller
- a Department of Dermatology , University Medical Center Utrecht , Utrecht , The Netherlands
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Parkar SP, Dherai AJ, Desai DC, Ashavaid TF. Thiopurine metabolite level and toxicity in Indians with inflammatory bowel disease. JGH OPEN 2017; 1:25-31. [PMID: 30483529 PMCID: PMC6206977 DOI: 10.1002/jgh3.12004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/23/2017] [Accepted: 08/07/2017] [Indexed: 11/06/2022]
Abstract
Background and Aim A lower dose requirement and higher toxicity of thiopurine is reported in Asian patients with inflammatory bowel disease (IBD) as compared with Caucasian patients. These reports are based on thiopurine methyltransferase measurement studies rather than metabolite estimation.We studied the utility of thiopurine metabolite estimation in Indian patients with IBD and compared dose and toxicity with Asian and Caucasian patients. Methods In this prospective study, 6-thioguanine nucleotide (6-TGN) and 6-methylmercaptopurine levels were determined by HPLC in 76 IBD patients treated with thiopurines. The levels were correlated with dose, disease activity, and toxicity. The dose-related metabolite levels and toxicity were compared with Caucasian and Asian patients reported in literature. Results Of the 76 patients (32 women, mean age: 35.9 [SD: 14.54] years, 36 Crohn's disease and 40 ulcerative colitis), 1 non-compliant patient had undetectable level of metabolites. Of the 75 patients, 21(28%) had therapeutic level of 6-TGN, 37(49%) had subtherapeutic level and 17(23%) had supratherapeutic level. The 6-methylmercaptopurine levels ranged up to 4971 pmol/8 × 108 red blood cells. Six (8%) patients showed toxicity. Thiopurine dose was optimized in 20 (26.31%) patients. Dose-based metabolite levels were comparable to Asian and Caucasian patients. The toxicity (8%) observed in our patients was less than that reported (12-39%). Conclusion Half of the patients in this study had low and a quarter had high 6-TGN levels. One-fourth of the patients needed dose modification. The dose-based metabolite levels were comparable and the toxicity was less than that reported in Asian and Caucasian patients.
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Affiliation(s)
- Suruchi P Parkar
- Department of Laboratory Medicine, Division of Gastroenterology P. D. Hinduja Hospital and Medical Research Centre Mumbai India
| | - Alpa J Dherai
- Department of Laboratory Medicine, Division of Gastroenterology P. D. Hinduja Hospital and Medical Research Centre Mumbai India
| | - Devendra C Desai
- Department of Laboratory Medicine, Division of Gastroenterology P. D. Hinduja Hospital and Medical Research Centre Mumbai India
| | - Tester F Ashavaid
- Department of Laboratory Medicine, Division of Gastroenterology P. D. Hinduja Hospital and Medical Research Centre Mumbai India
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Pelin M, Genova E, Fusco L, Marisat M, Hofmann U, Favretto D, Lucafò M, Taddio A, Martelossi S, Ventura A, Stocco G, Schwab M, Decorti G. Pharmacokinetics and pharmacodynamics of thiopurines in an in vitro model of human hepatocytes: Insights from an innovative mass spectrometry assay. Chem Biol Interact 2017; 275:189-195. [PMID: 28811125 DOI: 10.1016/j.cbi.2017.08.009] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2017] [Revised: 07/05/2017] [Accepted: 08/11/2017] [Indexed: 02/07/2023]
Abstract
AIM To apply an innovative LC-MS/MS method to quantify thiopurine metabolites in human hepatocytes and to associate them to cytotoxicity. METHODS Immortalized human hepatocytes (IHH cells) were treated for 48 and 96 h, with 1.4 × 10-4 M azathioprine and 1.1 × 10-3 M mercaptopurine, concentrations corresponding to the IC50 values calculated after 96 h exposure in previous cytotoxicity analysis. After treatments, cells were collected for LC-MS/MS analysis to quantify 11 thiopurine metabolites with different level of phosphorylation and viable cells were counted by trypan blue exclusion assay to determine thiopurines in vitro effect on cell growth and survival. Statistical significance was determined by analysis of variance (ANOVA). RESULTS Azathioprine and mercaptopurine had a significant time-dependent cytotoxic effect (p-value ANOVA = 0.012), with a viable cell count compared to controls of 55.5% and 67.5% respectively after 48 h and 23.7% and 36.1% after 96 h; no significant difference could be observed between the two drugs. Quantification of thiopurine metabolites evidenced that the most abundant metabolite was TIMP, representing 57.1% and 40.3% of total metabolites after 48 and 96 h. Total thiopurine metabolites absolute concentrations decreased over time: total mean content decreased from 469.9 pmol/million cells to 83.6 pmol/million cells (p-value ANOVA = 0.0070). However, considering the relative amount of thiopurine metabolites, TGMP content significantly increased from 11.4% cells to 26.4% (p-value ANOVA = 0.017). A significant association between thiopurine effects and viable cell counts could be detected only for MeTIMP: lower MeTIMP concentrations were associated with lower cell survival (p-value ANOVA = 0.011). Moreover, the ratio between MeTIMP and TGMP metabolites directly correlated with cell survival (p-value ANOVA = 0.037). CONCLUSION Detailed quantification of thiopurine metabolites in a human hepatocytes model provided useful insights on the association between thioguanine and methyl-thioinosine nucleotides with cell viability.
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Affiliation(s)
- Marco Pelin
- Department of Life Sciences, University of Trieste, I-34127 Trieste, Italy
| | - Elena Genova
- PhD School in Reproduction and Developmental Sciences, University of Trieste, I-34127 Trieste, Italy
| | - Laura Fusco
- PhD School in Chemistry, University of Trieste, I-34127 Trieste, Italy
| | - Monzer Marisat
- Department of Medical, Surgical and Health Sciences, University of Trieste, I-34127 Trieste, Italy
| | - Ute Hofmann
- Dr. Margarete Fischer-Bosch Institute of Clinical Pharmacology, D-70376 Stuttgart, Germany; University of Tübingen, Tübingen, Germany
| | - Diego Favretto
- Institute for Maternal and Child Health I.R.C.C.S. Burlo Garofolo, I-34137 Trieste, Italy
| | - Marianna Lucafò
- Department of Medical, Surgical and Health Sciences, University of Trieste, I-34127 Trieste, Italy
| | - Andrea Taddio
- Department of Medical, Surgical and Health Sciences, University of Trieste, I-34127 Trieste, Italy; Institute for Maternal and Child Health I.R.C.C.S. Burlo Garofolo, I-34137 Trieste, Italy
| | - Stefano Martelossi
- Institute for Maternal and Child Health I.R.C.C.S. Burlo Garofolo, I-34137 Trieste, Italy
| | - Alessandro Ventura
- Department of Medical, Surgical and Health Sciences, University of Trieste, I-34127 Trieste, Italy; Institute for Maternal and Child Health I.R.C.C.S. Burlo Garofolo, I-34137 Trieste, Italy
| | - Gabriele Stocco
- Department of Life Sciences, University of Trieste, I-34127 Trieste, Italy.
| | - Matthias Schwab
- Dr. Margarete Fischer-Bosch Institute of Clinical Pharmacology, D-70376 Stuttgart, Germany; University of Tübingen, Tübingen, Germany; Department of Clinical Pharmacology, University Hospital Tübingen, D-72076 Tübingen, Germany; Department of Pharmacy and Biochemistry, University of Tübingen, D-72076 Tübingen, Germany
| | - Giuliana Decorti
- Department of Medical, Surgical and Health Sciences, University of Trieste, I-34127 Trieste, Italy; Institute for Maternal and Child Health I.R.C.C.S. Burlo Garofolo, I-34137 Trieste, Italy
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Feuerstein JD, Cheifetz AS. Crohn Disease: Epidemiology, Diagnosis, and Management. Mayo Clin Proc 2017; 92:1088-1103. [PMID: 28601423 DOI: 10.1016/j.mayocp.2017.04.010] [Citation(s) in RCA: 184] [Impact Index Per Article: 26.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/15/2017] [Revised: 03/30/2017] [Accepted: 04/12/2017] [Indexed: 12/20/2022]
Abstract
Crohn disease is a chronic idiopathic inflammatory bowel disease condition characterized by skip lesions and transmural inflammation that can affect the entire gastrointestinal tract from the mouth to the anus. For this review article, we performed a review of articles in PubMed through February 1, 2017, by using the following Medical Subject Heading terms: crohns disease, crohn's disease, crohn disease, inflammatory bowel disease, and inflammatory bowel diseases. Presenting symptoms are often variable and may include diarrhea, abdominal pain, weight loss, nausea, vomiting, and in certain cases fevers or chills. There are 3 main disease phenotypes: inflammatory, structuring, and penetrating. In addition to the underlying disease phenotype, up to a third of patients will develop perianal involvement of their disease. In addition, in some cases, extraintestinal manifestations may develop. The diagnosis is typically made with endoscopic and/or radiologic findings. Disease management is usually with pharmacologic therapy, which is determined on the basis of disease severity and underlying disease phenotype. Although the goal of management is to control the inflammation and induce a clinical remission with pharmacologic therapy, most patients will eventually require surgery for their disease. Unfortunately, surgery is not curative and patients still require ongoing therapy even after surgery for disease recurrence. Importantly, given the risks of complications from both Crohn disease and the medications used to treat the disease process, primary care physicians play an important role in optimizing the preventative care management to reduce the risk of complications.
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Affiliation(s)
- Joseph D Feuerstein
- Department of Medicine and Division of Gastroenterology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA.
| | - Adam S Cheifetz
- Department of Medicine and Division of Gastroenterology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA
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Chapdelaine A, Mansour AM, Troyanov Y, Williamson DR, Doré M. Metabolite monitoring to guide thiopurine therapy in systemic autoimmune diseases. Clin Rheumatol 2017; 36:1341-1348. [PMID: 28130685 DOI: 10.1007/s10067-017-3554-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2016] [Revised: 12/22/2016] [Accepted: 01/18/2017] [Indexed: 02/06/2023]
Abstract
6-Thioguanine nucleotide (6-TGN) is the active metabolite of thiopurine drugs azathioprine and 6-mercaptopurine. 6-Methylmercaptopurine (6-MMP) is an inactive and potentially hepatotoxic metabolite. A subgroup of patients (shunters) preferentially produce 6-MMP instead of 6-TGN, therefore displaying thiopurine resistance and risk for hepatotoxicity. Outside inflammatory bowel disease literature, few data exist regarding individualized thiopurine therapy based on metabolite monitoring. This study sought to describe metabolite monitoring in patients receiving weight-based thiopurine for systemic autoimmune diseases. Patients were enrolled using a laboratory database, and data were retrospectively collected. The correlation between the highest thiopurine dose (mg/kg) and the 6-TGN concentration (pmol/8 × 108 erythrocytes) was estimated with Pearson's correlation coefficient. Seventy-one patients with various systemic autoimmune conditions were enrolled. The correlation between the thiopurine dose and the 6-TGN level was weak for the overall patient sample (r = 0.201, p = 0.092) and for the subgroup of non-shunters (r = 0.278, p = 0.053). Subjects with 6-MMP levels >5700 pmol/8 × 108 erythrocytes had more hepatic cytolysis compared to subjects with 6-MMP <5700, OR = 4.36 (CI 95% 1.18-16.13, p = 0.027). Twenty-two patients (31%) were identified as shunters. Six shunters developed hepatotoxicity, five of which had 6-MMP concentration >5700. Eleven non-shunters had hepatotoxicity, one of which had 6-MMP >5700. Thiopurine metabolite monitoring shows wide variability in 6-TGN levels among patients treated with weight-based thiopurine for systemic autoimmune diseases. Thirty-one percent of the patients in our series fulfilled the shunter definition. Thiopurine metabolite monitoring and dose adjustment to improve maintenance of remission and avoid hepatotoxicity should be studied prospectively.
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Affiliation(s)
- Aurélie Chapdelaine
- Department of Medicine, Hôpital du Sacré-Cœur de Montréal, 5400 Gouin Ouest, Montréal, Québec, H4J 1C5, Canada.
| | - Anne-Marie Mansour
- Department of Medicine, Hôpital du Sacré-Cœur de Montréal, 5400 Gouin Ouest, Montréal, Québec, H4J 1C5, Canada
- Faculty of Medicine, Université de Montréal, 5400 Gouin Ouest, Montréal, Québec, H4J 1C5, Canada
| | - Yves Troyanov
- Department of Medicine, Hôpital du Sacré-Cœur de Montréal, 5400 Gouin Ouest, Montréal, Québec, H4J 1C5, Canada
| | - David R Williamson
- Department of Pharmacy, Hôpital du Sacré-Cœur de Montréal, 5400 Gouin Ouest, Montréal, Québec, H4J 1C5, Canada
- Faculty of Pharmacy, Université de Montréal, 5400 Gouin Ouest, Montréal, Québec, H4J 1C5, Canada
| | - Maxime Doré
- Department of Pharmacy, Hôpital du Sacré-Cœur de Montréal, 5400 Gouin Ouest, Montréal, Québec, H4J 1C5, Canada
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Broekman MMTJ, Wong DR, Wanten GJA, Roelofs HM, van Marrewijk CJ, Klungel OH, Verbeek ALM, Hooymans PM, Guchelaar HJ, Scheffer H, Derijks LJJ, Coenen MJH, de Jong DJ. The glutathione transferase Mu null genotype leads to lower 6-MMPR levels in patients treated with azathioprine but not with mercaptopurine. THE PHARMACOGENOMICS JOURNAL 2017; 18:160-166. [PMID: 28045129 DOI: 10.1038/tpj.2016.87] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Received: 02/26/2016] [Revised: 11/07/2016] [Accepted: 11/14/2016] [Indexed: 12/21/2022]
Abstract
The conversion of azathioprine (AZA) to mercaptopurine (MP) is mediated by glutathione transferase Mu1 (GSTM1), alpha1 (GSTA1) and alpha2 (GSTA2). We designed a case-control study with data from the TOPIC trial to explore the effects of genetic variation on steady state 6-methylmercaptopurine ribonucleotide (6-MMPR) and 6-thioguanine nucleotide (6-TGN) metabolite levels. We included 199 patients with inflammatory bowel disease (126 on AZA and 73 on MP). GSTM1-null genotype carriers on AZA had two-fold lower 6-MMPR levels than AZA users carrying one or two copies of GSTM1 (2239 (1006-4587) versus 4371 (1897-7369) pmol/8 × 108 RBCs; P<0.01). In patients on MP (control group) 6-MMPR levels were comparable (6195 (1551-10712) versus 6544 (1717-11600) pmol/8 × 108 RBCs; P=0.84). The 6-TGN levels were not affected by the GSTM1 genotype. The presence of genetic variants in GSTA1 and GSTA2 was not related to the 6-MMPR and 6-TGN levels.
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Affiliation(s)
- M M T J Broekman
- Radboud University Medical Center, Radboud Institute for Molecular Life Sciences, Department of Gastroenterology, Nijmegen, The Netherlands
| | - D R Wong
- Department of Clinical Pharmacy, Pharmacology and Toxicology, Zuyderland Medical Center, Sittard-Geleen, The Netherlands
| | - G J A Wanten
- Radboud University Medical Center, Radboud Institute for Molecular Life Sciences, Department of Gastroenterology, Nijmegen, The Netherlands
| | - H M Roelofs
- Radboud University Medical Center, Radboud Institute for Molecular Life Sciences, Department of Gastroenterology, Nijmegen, The Netherlands
| | - C J van Marrewijk
- Radboud University Medical Center, Radboud Institute for Health Sciences, Department of Human Genetics, Nijmegen, The Netherlands
| | - O H Klungel
- Department of Pharmacoepidemiology and Pharmacotherapy, Utrecht University, Utrecht, The Netherlands
| | - A L M Verbeek
- Radboud University Medical Center, Radboud Institute for Health Sciences, Nijmegen, The Netherlands
| | - P M Hooymans
- Department of Clinical Pharmacy, Pharmacology and Toxicology, Zuyderland Medical Center, Sittard-Geleen, The Netherlands
| | - H-J Guchelaar
- Department of Clinical Pharmacy and Toxicology, Leiden University Medical Center, Leiden, The Netherlands
| | - H Scheffer
- Radboud University Medical Center, Radboud Institute for Health Sciences, Department of Human Genetics, Nijmegen, The Netherlands
| | - L J J Derijks
- Department of Clinical Pharmacy, Máxima Medical Center, Veldhoven, The Netherlands
| | - M J H Coenen
- Radboud University Medical Center, Radboud Institute for Health Sciences, Department of Human Genetics, Nijmegen, The Netherlands
| | - D J de Jong
- Radboud University Medical Center, Radboud Institute for Molecular Life Sciences, Department of Gastroenterology, Nijmegen, The Netherlands
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Ilan Y. Review article: novel methods for the treatment of non-alcoholic steatohepatitis - targeting the gut immune system to decrease the systemic inflammatory response without immune suppression. Aliment Pharmacol Ther 2016; 44:1168-1182. [PMID: 27778363 PMCID: PMC5216447 DOI: 10.1111/apt.13833] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/08/2016] [Revised: 07/28/2016] [Accepted: 09/28/2016] [Indexed: 12/14/2022]
Abstract
BACKGROUND The systemic immune system plays a role in inflammation and fibrogenesis associated with non-alcoholic steatohepatitis (NASH) and has become a potential target for drug development. In particular, the gut immune system has been suggested as a means for generating signals that can target the systemic immune system. AIM To describe seven novel methods being developed for the treatment of NASH that target the gut immune system for alleviation of the systemic inflammatory response, including oral administration of fatty-liver-derived proteins, anti-CD3 antibodies, tumour necrosis factor fusion protein, anti-lipopolysaccharide antibodies, glucosylceramide, delayed-release mercaptopurine, and soy-derived extracts. METHODS A search for these methods for oral immunotherapy for NASH was conducted. RESULTS Oral administration of these compounds provides an opportunity for immune modulation without immune suppression, with the advantage of being independent of a single molecular/inflammatory pathway. These modes of oral immune therapy demonstrate superior safety profiles, such that the patient is not exposed to general immune suppression. Moreover, these approaches target the whole spectrum of the disease and may serve as adjuvants to other therapies, such that they provide a platform for treatment of concomitant disorders in patients with NASH, including diabetes and hyperlipidaemia. Most of the compounds reviewed are currently in phase II trials, and it is anticipated that the acquisition of more clinical data in the next few years will enable the use of this new class of drugs for the treatment of NASH. CONCLUSION Oral immunotherapy may provide a novel platform for the treatment of NASH.
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Affiliation(s)
- Y. Ilan
- Gastroenterology and Liver UnitsDepartment of MedicineHadassah Hebrew University Medical CenterJerusalemIsrael
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Coskun M, Steenholdt C, de Boer NK, Nielsen OH. Pharmacology and Optimization of Thiopurines and Methotrexate in Inflammatory Bowel Disease. Clin Pharmacokinet 2016; 55:257-74. [PMID: 26255287 DOI: 10.1007/s40262-015-0316-9] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Improving the efficacy and reducing the toxicity of thiopurines and methotrexate (MTX) have been areas of intense basic and clinical research. An increased knowledge on pharmacodynamics and pharmacokinetics of these immunomodulators has optimized treatment strategies in inflammatory bowel disease (IBD). This review focuses on the metabolism and mode of action of thiopurines and MTX, and provides an updated overview of individualized treatment strategies in which efficacy in IBD can be increased without compromising safety. The patient-based monitoring instruments adapted into clinical practice include pretreatment thiopurine S-methyltransferase testing, thiopurine metabolite monitoring, and blood count measurements that may help guiding the dosage to improve clinical outcome. Other approaches for optimizing thiopurine therapy in IBD include combination therapy with allopurinol, 5-aminosalicylates, and/or biologics. Similar strategies are yet to be proven effective in improving the outcome of MTX therapy. Important challenges for the management of IBD in the future relate to individualized dosing of immunomodulators for maximal efficacy with minimal risk of side effects. As low-cost conventional immunomodulators still remain a mainstay in pharmacotherapy of IBD, more research remains warranted, especially to substantiate these tailored management strategies in controlled clinical trials.
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Affiliation(s)
- Mehmet Coskun
- Department of Gastroenterology, Herlev Hospital, University of Copenhagen, Herlev, Denmark. .,Department of Biology and Biotech Research and Innovation Centre (BRIC), The Bioinformatics Centre, University of Copenhagen, Copenhagen, Denmark.
| | - Casper Steenholdt
- Department of Gastroenterology, Herlev Hospital, University of Copenhagen, Herlev, Denmark
| | - Nanne K de Boer
- Department of Gastroenterology and Hepatology, VU University Medical Center, Amsterdam, The Netherlands
| | - Ole Haagen Nielsen
- Department of Gastroenterology, Herlev Hospital, University of Copenhagen, Herlev, Denmark
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González-Lama Y, Gisbert JP. Monitoring thiopurine metabolites in inflammatory bowel disease. Frontline Gastroenterol 2016; 7:301-307. [PMID: 28839871 PMCID: PMC5369498 DOI: 10.1136/flgastro-2015-100681] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/30/2015] [Revised: 03/09/2016] [Accepted: 03/16/2016] [Indexed: 02/04/2023] Open
Abstract
Thiopurines (azathioprine and mercaptopurine) are one of the immunosuppressive mainstays for the treatment of inflammatory bowel disease. In spite of its widespread use, thiopurine metabolism is still not fully understood, and a significant proportion of patients suffer toxicity or lack of efficacy. Different enzymatic pathways with individual variations constitute a pharmacogenetic model that seems to be suitable for monitoring and therapeutic intervention. This review is focused on current concepts and recent research that may help clinicians to rationally optimise thiopurine treatment in patients with inflammatory bowel disease.
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Affiliation(s)
- Yago González-Lama
- Gastroenterology and Hepatology Department, Puerta de Hierro University Hospital, Majadahonda, Madrid, Spain
| | - Javier P Gisbert
- Gastroenterology Unit, Hospital Universitario de La Princesa and Instituto de Investigación Sanitaria Princesa (IIS-IP), Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBEREHD), Madrid, Madrid, Spain
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Vögelin M, Biedermann L, Frei P, Vavricka SR, Scharl S, Zeitz J, Sulz MC, Fried M, Rogler G, Scharl M. The Impact of Azathioprine-Associated Lymphopenia on the Onset of Opportunistic Infections in Patients with Inflammatory Bowel Disease. PLoS One 2016; 11:e0155218. [PMID: 27214202 PMCID: PMC4877071 DOI: 10.1371/journal.pone.0155218] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2016] [Accepted: 04/26/2016] [Indexed: 12/18/2022] Open
Abstract
Background Thiopurines are known to cause lymphopenia (<1,500 lymphocytes/μl). As severe lymphopenia (<500C/μl) is associated with opportunistic infections, we investigated severity of thiopurine-related lymphopenia and development of opportunistic infections in our tertiary referral centre. Methods We retrospectively screened medical records of 1,070 IBD patients and identified 100 individuals that developed a total of 161 episodes of lymphopenia during thiopurine treatment between 2002 and 2014. Occurrence of opportunistic infections was documented. A control group consisted of IBD patients receiving thiopurines but without developing lymphopenia. Results Of a total of 161 episodes of lymphopenia, 23% were severe (<500C/μl). In this subgroup, thiopurine dosing was modified in 64% (dosage reduction: 32%, medication discontinued: 32%). We identified 9 cases (5.5%) of opportunistic infections, of which only two occurred during severe lymphopenia. One opportunistic infection (4.5%) was identified in the control group. No association was found between opportunistic infections and severity of lymphopenia. All patients who suffered from opportunistic infections were receiving additional immunosuppressive medication. Conclusion Our patients treated with thiopurines rarely developed severe lymphopenia and opportunistic infections did not occur more often than in the control group. A careful monitoring of lymphocytes and prophylactic adjustment of thiopurine therapy might contribute to this low incidence.
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Affiliation(s)
- Marius Vögelin
- Division of Gastroenterology and Hepatology, University Hospital Zurich, University of Zurich, Zurich, Switzerland
| | - Luc Biedermann
- Division of Gastroenterology and Hepatology, University Hospital Zurich, University of Zurich, Zurich, Switzerland
| | - Pascal Frei
- Division of Gastroenterology and Hepatology, University Hospital Zurich, University of Zurich, Zurich, Switzerland
| | - Stephan R. Vavricka
- Division of Gastroenterology and Hepatology, University Hospital Zurich, University of Zurich, Zurich, Switzerland
- Division of Gastroenterology and Hepatology, Stadtspital Triemli, Zurich, Switzerland
- Zurich Center for Integrative Human Physiology, University of Zurich, Zurich, Switzerland
| | - Sylvie Scharl
- Division of Gastroenterology and Hepatology, University Hospital Zurich, University of Zurich, Zurich, Switzerland
| | - Jonas Zeitz
- Division of Gastroenterology and Hepatology, University Hospital Zurich, University of Zurich, Zurich, Switzerland
| | - Michael C. Sulz
- Division of Gastroenterology and Hepatology, University Hospital Zurich, University of Zurich, Zurich, Switzerland
- Division of Gastroenterology and Hepatology, Kantonsspital St. Gallen, St. Gallen, Switzerland
| | - Michael Fried
- Division of Gastroenterology and Hepatology, University Hospital Zurich, University of Zurich, Zurich, Switzerland
- Division of Gastroenterology and Hepatology, Stadtspital Triemli, Zurich, Switzerland
| | - Gerhard Rogler
- Division of Gastroenterology and Hepatology, University Hospital Zurich, University of Zurich, Zurich, Switzerland
- Division of Gastroenterology and Hepatology, Stadtspital Triemli, Zurich, Switzerland
| | - Michael Scharl
- Division of Gastroenterology and Hepatology, University Hospital Zurich, University of Zurich, Zurich, Switzerland
- Division of Gastroenterology and Hepatology, Stadtspital Triemli, Zurich, Switzerland
- * E-mail:
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Allen PB, Peyrin-Biroulet L. Immunomodulators for the treatment of Crohn's disease in adults: optimal use and prospects for future drug treatments. Expert Rev Clin Immunol 2016; 12:741-9. [PMID: 26900725 DOI: 10.1586/1744666x.2016.1154789] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Crohn's disease (CD) requires treatment beyond symptoms by enabling and maintaining mucosal healing and therefore clinical remission. However, with the increasing use of biologics there have been safety concerns and there is a significant cost implication with the early use of biologics. Therefore, it is imperative that patients with severe/complicated disease or poor prognostic factors are treated with an aggressive strategy while all remaining patients should be treated in a step-up strategy. The potential for disease modification with thiopurines and methotrexate is debated in CD when they are used as a monotherapy. In this review we discuss existing and newer therapies that have recently been developed for CD. We will also provide an algorithm for current management of adult CD patients in routine clinical practice.
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Affiliation(s)
- Patrick B Allen
- a Gastroenterology , Ulster Hospital , Belfast , N. Ireland, UK
| | - Laurent Peyrin-Biroulet
- b Department of Gastroenterology , University Hospital of Nancy-Brabois , Vandoeuvre-lès-Nancy , France
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Oral immune therapy: targeting the systemic immune system via the gut immune system for the treatment of inflammatory bowel disease. Clin Transl Immunology 2016; 5:e60. [PMID: 26900473 PMCID: PMC4735066 DOI: 10.1038/cti.2015.47] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2015] [Revised: 11/04/2015] [Accepted: 12/22/2015] [Indexed: 12/13/2022] Open
Abstract
Inflammatory bowel diseases (IBD) are associated with an altered systemic immune response leading to inflammation-mediated damage to the gut and other organs. Oral immune therapy is a method of systemic immune modulation via alteration of the gut immune system. It uses the inherit ability of the innate system of the gut to redirect the systemic innate and adaptive immune responses. Oral immune therapy is an attractive clinical approach to treat autoimmune and inflammatory disorders. It can induce immune modulation without immune suppression, has minimal toxicity and is easily administered. Targeting the systemic immune system via the gut immune system can serve as an attractive novel therapeutic method for IBD. This review summarizes the current data and discusses several examples of oral immune therapeutic methods for using the gut immune system to generate signals to reset systemic immunity as a treatment for IBD.
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Treatment Nonadherence in Inflammatory Bowel Disease: Identification, Scope, and Management Strategies. Inflamm Bowel Dis 2015; 21:2979-84. [PMID: 26355470 DOI: 10.1097/mib.0000000000000581] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Treatment adherence is of critical importance in the management of patients with IBD. Poor adherence can lead to increased disease activity, loss of response to therapy, and increased costs of care. It has been well established that adherence to long-term therapy for chronic illnesses is extremely poor, averaging around 50% in developed countries. Measured rates of nonadherence in IBD are similar, but vary depending on the type of therapy and the population being observed. This article reviews the scientific data on treatment nonadherence in IBD. The methods commonly used to evaluate treatment adherence investigation are reviewed. The consequences and scope of treatment nonadherence are summarized. Finally, the scientific data on management strategies to address the problem of treatment nonadherence are explored.
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Israeli E, Goldin E, Fishman S, Konikoff F, Lavy A, Chowers Y, Melzer E, Lahat A, Mahamid M, Shirin H, Nussinson E, Segol O, Ya'acov AB, Shabbat Y, Ilan Y. Oral administration of non-absorbable delayed release 6-mercaptopurine is locally active in the gut, exerts a systemic immune effect and alleviates Crohn's disease with low rate of side effects: results of double blind Phase II clinical trial. Clin Exp Immunol 2015; 181:362-72. [PMID: 25846055 DOI: 10.1111/cei.12640] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2015] [Revised: 03/17/2015] [Accepted: 03/17/2015] [Indexed: 12/18/2022] Open
Abstract
Therapy for Crohn's disease (CD) with thiopurines is limited by systemic side effects. A novel formulation of fixed-dose, delayed-release 6-mercaptopurine (DR-6MP) was developed, with local effect on the gut immune system and minimal absorption. The aim of this study was to evaluate the safety and efficacy of DR-6MP in patients with moderately severe CD compared to systemically delivered 6-mercaptopurine (Purinethol). Seventy CD patients were enrolled into a 12-week, double-blind controlled trial. The primary end-point was the percentage of subjects with clinical remission [Crohn's Disease Activity Index (CDAI) < 150] or clinical response (100-point CDAI reduction). Twenty-six (56·5%) and 13 (54·2%) subjects from the DR-6MP and Purinethol cohorts, respectively, completed the study. DR-6MP had similar efficacy to Purinethol following 12 weeks of treatment. However, the time to maximal clinical response was 8 weeks for DR-6MP versus 12 weeks for Purinethol. A higher proportion of patients on DR-6MP showed clinical remission at week 8. A greater improvement in Inflammatory Bowel Disease Questionnaire (IBDQ) score was noted in the DR-6MP group. DR-6MP led to a decrease of CD62(+) expression on T cells, implying a reduction of lymphocyte adhesion to site of inflammation. DR-6MP was safer than Purinethol, with significantly fewer adverse events (AEs). There was no evidence of drug-induced leucopenia in the DR-6MP group; the proportion of subjects who developed hepatotoxicity was lower for the DR-6MP. Non-absorbable DR-6MP is safe and biologically active in the gut. It is clinically effective, exerting a systemic immune response with low systemic bioavailability and a low incidence of side effects.
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Affiliation(s)
- E Israeli
- Gastroenterology and Liver Units, Department of Medicine, Hebrew University-Hadassah Medical Center, Jerusalem
| | - E Goldin
- Department of Gastroenterology, Shaarei Zedek Medical Center, Jerusalem
| | - S Fishman
- Department of Gastroenterology, Tel Aviv-Sourasky Medical Center, Tel Aviv
| | - F Konikoff
- Department of Gastroenterology, Meir Medical Center, Kfar Saba
| | - A Lavy
- Department of Gastroenterology, Bnai Zion Hospital, Haifa
| | - Y Chowers
- Department of Gastroenterology, Rambam Health Care Campus and Bruce Rappaport School of Medicine, Technion Israel Institute of Technology, Haifa
| | - E Melzer
- Department of Gastroenterology, Kaplan Medical Center, Rehovot
| | - A Lahat
- Department of Gastroenterology, Sheba Medical Center, Tel Hashomer
| | - M Mahamid
- Department of Gastroenterology, Holy Family Hospital, Nazareth
| | - H Shirin
- Department of Gastroenterology, Assaf Harofeh Medical Center, Zerifin
| | - E Nussinson
- Department of Gastroenterology, Ha'emek Medical Center, Afula
| | - O Segol
- Department of Gastroenterology, Carmel Medical Center, Haifa, Israel
| | - A Ben Ya'acov
- Gastroenterology and Liver Units, Department of Medicine, Hebrew University-Hadassah Medical Center, Jerusalem
| | - Y Shabbat
- Gastroenterology and Liver Units, Department of Medicine, Hebrew University-Hadassah Medical Center, Jerusalem
| | - Y Ilan
- Gastroenterology and Liver Units, Department of Medicine, Hebrew University-Hadassah Medical Center, Jerusalem
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De Nicolò A, Agnesod D, Simiele M, Riganò D, Adriani A, Canaparo R, Astegiano M, Rizzetto M, Di Perri G, D’Avolio A. UPLC–MS/MS method for quantification of the azathioprine metabolites 6-mercaptoguanosine and 6-methylmercaptopurine riboside in peripheral blood mononuclear cells. J Pharm Biomed Anal 2014; 98:271-8. [DOI: 10.1016/j.jpba.2014.05.040] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2014] [Revised: 05/28/2014] [Accepted: 05/31/2014] [Indexed: 10/25/2022]
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Renna S, Cottone M, Orlando A. Optimization of the treatment with immunosuppressants and biologics in inflammatory bowel disease. World J Gastroenterol 2014; 20:9675-90. [PMID: 25110407 PMCID: PMC4123358 DOI: 10.3748/wjg.v20.i29.9675] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/29/2013] [Revised: 01/18/2014] [Accepted: 04/28/2014] [Indexed: 02/06/2023] Open
Abstract
Many placebo controlled trials and meta-analyses evaluated the efficacy of different drugs for the treatment of inflammatory bowel disease (IBD), including immunosuppressants and biologics. Their use is indicated in moderate to severe disease in non responders to corticosteroids and in steroid-dependent patients, as induction and maintainance treatment. Infliximab, as well as cyclosporine, is considered a second line therapy in the case of severe ulcerative colitis, or non-responders to intravenous corticosteroids. An adequate dosage and duration of therapy with thiopurines should be reached before evaluating their efficacy. Methotrexate is a valid option in patients with Crohn's disease but its use is confined to patients who are intolerant or non-responders to thiopurines. Evidence for the use of methotrexate in ulcerative colitis is insufficient. The use of thalidomide and mycophenolate mofetil is not recommended in patients with inflammatory bowel disease, these treatments could be considered in case of failure of all other therapeutic options. In patients with moderately active ulcerative colitis, refractory to thiopurines, the use of tacrolimus is considered an alternative to biologics. An increase of the dose or a decrease in the interval of administration of biological treatment could be useful in the presence of an incomplete clinical response. In the case of primary failure of an anti-tumor necrosis factor alpha a switch to another one should be considered. Data on the efficacy of combination therapy are up to now insufficient to consider this strategy in all IBD patients. The final outcome of the treatment should be considered the clinical remission, with mucosa healing, and not the clinical response. The evaluation of serum concentration of thiopurine methyl transferase activity, thiopurine metabolites, biologic serum levels and antibiologic antibodies could be useful for the management of the treatment but it has not been routinely applied in clinical practice. The evidence of high risk development of lymphoma and cutaneous malignancies should be considered in patients treated with immunosuppressants and biologics for a long period.
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Konidari A, Matary WE. Use of thiopurines in inflammatory bowel disease: Safety issues. World J Gastrointest Pharmacol Ther 2014; 5:63-76. [PMID: 24868487 PMCID: PMC4023326 DOI: 10.4292/wjgpt.v5.i2.63] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/22/2013] [Accepted: 02/19/2014] [Indexed: 02/06/2023] Open
Abstract
Thiopurines are widely used for maintenance treatment of inflammatory bowel disease. Inter-individual variability in clinical response to thiopurines may be attributed to several factors including genetic polymorphisms, severity and chronicity of disease, comorbidities, duration of administration, compliance issues and use of concomitant medication, environmental factors and clinician and patient preferences. The purpose of this review is to summarise the current evidence on thiopurine safety and toxicity, to describe adverse drug events and emphasise the significance of drug interactions, and to discuss the relative safety of thiopurine use in adults, elderly patients, children and pregnant women. Thiopurines are safe to use and well tolerated, however dose adjustment or discontinuation of treatment must be considered in cases of non-response, poor compliance or toxicity. Drug safety, clinical response to treatment and short to long term risks and benefits must be balanced throughout treatment duration for different categories of patients. Treatment should be individualised and stratified according to patient requirements. Enzymatic testing prior to treatment commencement is advised. Surveillance with regular clinic follow-up and monitoring of laboratory markers is important. Data on long term efficacy, safety of thiopurine use and interaction with other disease modifying drugs are lacking, especially in paediatric inflammatory bowel disease. High quality, collaborative clinical research is required so as to inform clinical practice in the future.
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Beswick L, Friedman AB, Sparrow MP. The role of thiopurine metabolite monitoring in inflammatory bowel disease. Expert Rev Gastroenterol Hepatol 2014; 8:383-92. [PMID: 24684593 DOI: 10.1586/17474124.2014.894878] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Thiopurines are the mainstay of medical management in inflammatory bowel disease (IBD), especially in the maintenance of disease remission. Given the limited IBD armamentarium it is important to optimize each therapy before switching to an alternative drug. Conventional weight based dosing of thiopurines in IBD leads to intolerance or inefficacy in many patients. More recently increased knowledge of their metabolism has allowed for dose optimization using thiopurine metabolite levels, namely 6-thioguanine nucleotides and 6-methylmercaptopurine, with the potential for improved outcomes in patients with IBD. This review will outline the current understanding of thiopurine metabolism and pharmacogenomics and will describe the clinical application of this knowledge in the optimization of thiopurines in individual patients.
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Affiliation(s)
- Lauren Beswick
- Department of Gastroenterology, Alfred Health and Monash University, Commercial Road, Melbourne, 3004 Victoria, Australia
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Association between 6-thioguanine nucleotides levels and clinical remission in inflammatory disease: a meta-analysis. Inflamm Bowel Dis 2014; 20:464-71. [PMID: 24418904 DOI: 10.1097/01.mib.0000439068.71126.00] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
BACKGROUND A previous meta-analysis suggested that 6-thioguanine nucleotides levels are associated with clinical remission in inflammatory bowel disease. It was criticized because of the relatively small number of patients included in this meta-analysis and heterogeneity between studies. Recent studies provided conflicting results, and the source of those discrepancies has yet to be explored. METHODS A comprehensive, computerized literature search was conducted in Medline, ISI Web of Science, and EMBASE until December 31, 2012. A combined odd ratio with its 95% confidence interval was calculated using a fixed effects model based on the Mantel-Haenszel method. Between-study heterogeneity was assessed using Cochran's Q statistic. RESULTS Seventeen studies enrolling 2049 patients with inflammatory bowel disease were analyzed. A significant heterogeneity was found in the overall analysis (P = 0.005). As heterogeneity among studies could be explained by differences in metabolite assay methods, an analysis including only studies using the reference method by Lennard et al (N = 10) was performed, and the pooled odds ratio for clinical remission among patients with 6-thioguanine nucleotides levels over a cut-off value between 230 and 260 pmol/8.10^8 RBC was 3.15 (95% confidence interval, 2.41-4.11). CONCLUSIONS This meta-analysis clearly establishes an association between 6-thioguanine nucleotides levels and clinical remission rates in patients with inflammatory bowel disease and explains the heterogeneity of results among selected studies. The lack of standardization in 6-thioguanine nucleotides assays is responsible for recent contradictory results. Whether therapeutic drug monitoring of thiopurines should be systematically used in clinical practice in inflammatory bowel disease to improve disease outcomes will require further investigation.
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Doré M, Frenette AJ, Mansour AM, Troyanov Y, Bégin J. Febuxostat as a novel option to optimize thiopurines' metabolism in patients with inadequate metabolite levels. Ann Pharmacother 2014; 48:648-51. [PMID: 24523395 DOI: 10.1177/1060028014521389] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
OBJECTIVE To report the use of febuxostat in order to potentiate thiopurines' metabolism in a patient on azathioprine (AZA) therapy with low metabolite 6-thioguanine nucleotides (6-TGN) levels and elevated metabolite 6-methylmercaptopurine (6-MMP) levels. CASE SUMMARY A 44-year-old woman with a history of anti-signal recognition particle necrotizing myopathy was treated with AZA-allopurinol combination therapy. When she developed an atypical drug-induced hypersensitivity syndrome, allopurinol was replaced by the new xanthine oxidase (XO) inhibitor febuxostat, at a daily dose of 40 mg. Febuxostat-AZA combination was successful with 6-TGN reaching therapeutic levels while 6-MMP levels remained low. After 5 months, she developed similar manifestations that she had presented on AZA-allopurinol combination. Febuxostat and AZA were then stopped. DISCUSSION AZA and 6-MP are both inactive pro-drugs that undergo a complex metabolic transformation leading to active 6-TGN and potentially hepatotoxic 6-MMP. Some patients with unfavorable thiopurine metabolism might benefit from addition of XO inhibitor allopurinol in order to potentiate 6-TGN and reduce 6-MMP levels. It is likely that febuxostat, via its XO inhibition, would exhibit the same effect on thiopurines' metabolism. CONCLUSION It has been shown that low dose of febuxostat was able to prevent hypermethylation and to potentiate 6-TGN levels in an AZA-treated patient. Thus, febuxostat could be useful in optimizing thiopurines' metabolism, but more data are needed before this practice can be recommended. The mechanisms by which febuxostat optimizes thiopurines' metabolism remain to be confirmed. Also, the optimal dose of febuxostat for this use remains to be determined.
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Affiliation(s)
- Maxime Doré
- Hôpital du Sacré-Coeur de Montréal, Montreal, Quebec, Canada
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