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Akbar K Waljee, Kay Sauder, Anand Patel, Sandeep Segar, Boang Liu, Yiwei Zhang, Ji Zhu, Ryan W Stidham, Ulysses Balis, Peter D R Higgins
Background and Aims: Big data analytics leverage patterns in data to harvest valuable information, but are rarely implemented in clinical care. Optimising thiopurine therapy for inflammatory bowel disease [IBD] has proved difficult. Current methods using 6-thioguanine nucleotide [6-TGN] metabolites have failed in randomized controlled trials [RCTs], and have not been used to predict objective remission [OR]. Our aims were to: 1) develop machine learning algorithms [MLA] using laboratory values and age to identify patients in objective remission on thiopurines; and 2) determine whether achieving algorithm-predicted objective remission resulted in fewer clinical events per year...
March 14, 2017: Journal of Crohn's & Colitis
Melissa A Sheiko, Shikha S Sundaram, Kelley E Capocelli, Zhaoxing Pan, Annette M McCoy, Cara L Mack
OBJECTIVES: Autoimmune hepatitis (AIH) is a common pediatric liver disease and long-term remission is usually maintained with azathioprine (AZA). There is no consensus on the target range for AZA active metabolite 6-thioguanine (6-TGN) levels in pediatric AIH. The aim of this study was to characterize the outcomes of pediatric patients with AIH and determine correlations between AZA dosing or 6-TGN metabolite levels and biochemical remission. METHODS: A retrospective chart review was performed and data on presentation, laboratories including AZA metabolite levels, medication use and outcomes was collected...
March 7, 2017: Journal of Pediatric Gastroenterology and Nutrition
R Mao, J Guo, S Ben Horin, M Chen
No abstract text is available yet for this article.
February 1, 2017: Journal of Crohn's & Colitis
Aurélie Chapdelaine, Anne-Marie Mansour, Yves Troyanov, David R Williamson, Maxime Doré
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...
January 27, 2017: Clinical Rheumatology
M M T J Broekman, D R Wong, G J A Wanten, H M Roelofs, C J van Marrewijk, O H Klungel, A L M Verbeek, P M Hooymans, H-J Guchelaar, H Scheffer, L J J Derijks, M J H Coenen, D J de Jong
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 × 10(8) RBCs; P<0...
January 3, 2017: Pharmacogenomics Journal
X Zhu, X-D Wang, K Chao, M Zhi, H Zheng, H-L Ruan, S Xin, N Ding, P-J Hu, M Huang, X Gao
BACKGROUND: Thiopurine-induced leukopenia is the most common dangerous adverse event in Asians. NUDT15 R139C was recently proposed to be a promising biomarker for leukopenia with thiopurine therapy in Asians, but this has not been replicated in the Chinese population. AIM: To investigate the influence of NUDT15 R139C, thiopurine S-methyltransferase (TPMT), 6-TGN and 6-MMPR on thiopurine-induced leukopenia in Chinese patients with Crohn's disease. METHODS: Clinical and epidemiological characteristics were reviewed from medical records...
November 2016: Alimentary Pharmacology & Therapeutics
D Zochowska, J Zegarska, E Hryniewiecka, E Samborowska, R Jazwiec, W Tszyrsznic, A Borowiec, M Dadlez, L Paczek
BACKGROUND: 6-Mercaptopurine (6-MP) and its prodrug azathioprine (AZA) are used in many autoimmune diseases and after solid-organ transplantation. Their properties are mediated by active metabolites, 6-thioguanine nucleotides (6-TGN), and 6-methylmercaptopurine (6-MMP). The most common adverse effects are myelo- and hepato-toxicity. The aim of the study was quantification of 6-TG and 6-MMP, with the use of liquid chromatography combined with tandem mass spectrometry (LC/MS/MS) in solid-organ transplant recipients...
June 2016: Transplantation Proceedings
May Fakhoury, Evelyne Jacqz-Aigrain, Tiphaine de Beaumais, Yves Médard
6-mercaptopurine, a key drug for the treatment of acute lymphoblastic leukaemia in children, is a prodrug metabolized into 6-thioguanine (6-TGN) which are the active compounds and into methylated metabolites, primary by thiopurine S-methyltransferase enzyme (TPMT). This enzyme displays important inter subject variability linked to a genetic polymorphism: when treated with standard doses of thiopurine, TPMT-deficient and heterozygous patients are at great risk for developing severe and potentially life-threatening toxicity (hematopoietic, hepatic, mucositis...
May 2010: Thérapie
Romein W G Dujardin, Berrie Meijer, Nanne K H de Boer, Geert R D'Haens, Mark Löwenberg
BACKGROUND: Thiopurines are commonly used drugs in inflammatory bowel disease. Intracellular levels of thiopurine metabolites [i.e. 6-thioguaninenucleotides (6-TGN)] are associated with efficacy and toxicity. Because 6-TGN measurement is not globally available, the mean corpuscular volume (MCV) has been proposed as a surrogate marker for monitoring thiopurine therapy. AIMS: To analyze the relationship between MCV and efficacy of thiopurines, defined as either response to therapy or 6-TGN levels...
September 2016: European Journal of Gastroenterology & Hepatology
Qiuyuan Liu, Yanyan Wang, Qiao Mei, Wei Han, Jing Hu, Naizhong Hu
OBJECTIVE: It remains controversial whether 6-thioguanine nucleotide (6-TGN)-based dose adjusting can be beneficial in azathioprine (AZA) therapy. This study is designed to assess the role of 6-TGN concentrations in maintaining clinical remission in Chinese patients with Crohn's disease (CD). MATERIAL AND METHOD: We performed a prospective observational study and collected data of CD patients in the First Affiliated Hospital of Anhui Medical University from June 2013 to April 2014...
September 2016: Scandinavian Journal of Gastroenterology
Zhang Fangbin, Gao Xiang, Ding Liang, Liu Hui, Wang Xueding, Chen Baili, Bi Huichang, Xiao Yinglian, Cheng Peng, Zhao Lizi, Chu Yanjun, Xu Feng, Chen Minhu, Huang Min, Hu Pinjin
Up to approximately 40% to 50% of patients discontinue thiopurine therapy during the course of inflammatory bowel disease (IBD). We investigated the role of the metabolite thiopurine in IBD treatment. This was a prospective study. IBD patients receiving azathioprine (AZA) were prospectively included. Thiopurine methyltransferase (TPMT) genotypes were examined before therapy, and thiopurine metabolite levels were examined at weeks 2, 4, 8, 12, 24, and 48. In total, 132 patients were included. The frequency of leucopenia increased at 6-thioguanine nucleotide (6-TGN) levels ≥420  pmol/8 × 10(8) RBC (odds ratio [OR] = 7...
April 2016: Medicine (Baltimore)
Nicole M Giamanco, Bethany S Cunningham, Laura S Klein, Dina S Parekh, Anne B Warwick, Kenneth Lieuw
6-Mercaptopurine (6-MP) is the mainstay of treatment for acute lymphoblastic leukemia and lymphoblastic lymphoma. It is metabolized into the pharmacologically active, 6-thioguanine nucleotide (6-TGN), and 6-methyl mercaptopurine nucleotides (6-MMPN), which is associated with hepatotoxicity that jeopardizes antileukemic therapy. Allopurinol alters the metabolism of 6-MP to increase 6-TGN levels and decreases 6-methyl mercaptopurine nucleotides levels. We report 2 cases in which combination therapy of allopurinol with 6-MP was used successfully to avoid hepatotoxicity while delivering adequate 6-TGN levels...
March 2016: Journal of Pediatric Hematology/oncology
Ayumi Asada, Atsushi Nishida, Makoto Shioya, Hirotsugu Imaeda, Osamu Inatomi, Shigeki Bamba, Katsuyuki Kito, Mitsushige Sugimoto, Akira Andoh
BACKGROUND: NUDT15 R139C (rs116855232) is a recently identified genetic factor responsible for thiopurine-induced leukocytopenia and hair loss. In this study, we investigated the association of NUDT15 R139C with 6-thioguanine nucleotide (6-TGN) levels and thiopurine-induced leukocytopenia in Japanese patients with inflammatory bowel disease (IBD). METHODS: Two hundred and sixty-four subjects (103 healthy volunteers and 161 IBD patients treated with thiopurines) were enrolled...
January 2016: Journal of Gastroenterology
Sophie A van den Berg, Marjon de Boer, Andrea E van der Meulen-de Jong, Jeroen M Jansen, Frank Hoentjen, Maurice G V M Russel, Nofel Mahmmod, Adriaan A van Bodegraven, C Janneke van der Woude, Chris J J Mulder, Nanne K H de Boer
BACKGROUND AND AIMS: Conventional thiopurine [azathioprine and mercaptopurine] treatment during pregnancy in patients with inflammatory bowel disease [IBD] is considered to be safe; however data on the safety and teratogenicity of the non-conventional thiopurine tioguanine [TG] in pregnant IBD patients are lacking. We aim to describe the safety and teratogenicity of TG treatment during pregnancy in IBD patients. METHODS: This was a retrospective, multicentre descriptive case series of female IBD patients using TG during pregnancy...
February 2016: Journal of Crohn's & Colitis
N M Heerasing, J F Ng, D Dowling
BACKGROUND: The thiopurine drugs, 6-mercaptopurine and azathioprine, remain the mainstay of immunomodulator therapy for inflammatory bowel disease (IBD). Optimal management depends on achieving therapeutic levels of 6-thioguanine (6-TGN), but measuring thiopurine metabolites is associated with significant cost. Thiopurines cause lymphopenia and an increase in mean corpuscular volume (MCV). It is unclear whether any clinically useful correlation exists between 6-TGN levels and lymphocyte count or MCV...
April 2016: Internal Medicine Journal
Shunichi Odahara, Kan Uchiyama, Takahiro Kubota, Zensho Ito, Shinichiro Takami, Hiroko Kobayashi, Keisuke Saito, Shigeo Koido, Toshifumi Ohkusa
Azathioprine (AZA) is frequently used in patients with inflammatory bowel disease (IBD). However, toxic adverse reactions frequently develop and limit the clinical benefits. Currently, the precise mechanisms underlying thiopurine-related toxicity are not well understood. To investigate the relationship between the extent of thiopurine metabolism and adverse reactions in Japanese IBD patients, we prospectively observed 48 IBD patients who received AZA. We analyzed the thiopurine S-methyltransferase (TPMT) and inosine triphosphate pyrophosphatase (ITPA) gene mutations and measured the concentrations of 6-thioguanine nucleotide (6-TGN) continuously for 52 weeks...
2015: PloS One
Devaraj Jayachandran, José Laínez-Aguirre, Ann Rundell, Terry Vik, Robert Hannemann, Gintaras Reklaitis, Doraiswami Ramkrishna
6-Mercaptopurine (6-MP) is one of the key drugs in the treatment of many pediatric cancers, auto immune diseases and inflammatory bowel disease. 6-MP is a prodrug, converted to an active metabolite 6-thioguanine nucleotide (6-TGN) through enzymatic reaction involving thiopurine methyltransferase (TPMT). Pharmacogenomic variation observed in the TPMT enzyme produces a significant variation in drug response among the patient population. Despite 6-MP's widespread use and observed variation in treatment response, efforts at quantitative optimization of dose regimens for individual patients are limited...
2015: PloS One
Shi Sum Poon, Rebecca Asher, Richard Jackson, Andrew Kneebone, Paul Collins, Chris Probert, Martyn Dibb, Sreedhar Subramanian
INTRODUCTION: Optimal levels of the thiopurine metabolite, 6-thioguanine nucleotides [6-TGN] correlate with remission of inflammatory bowel disease [IBD]. Apart from variations in the thiopurine methyl transferase [TPMT] gene, little is known about other predictors of 6-TGN levels. Obesity adversely affects response to infliximab and adalimumab and clinical course in IBD, but little is known about the interaction of thiopurines and obesity. We investigated the relationship between body mass index [BMI] and 6-TGN levels and sought to examine other predictors of 6-TGN levels...
August 2015: Journal of Crohn's & Colitis
Joany E Kreijne, Margien L Seinen, Abraham J Wilhelm, Gerd Bouma, Chris J Mulder, Adriaan A van Bodegraven, Nanne K H de Boer
BACKGROUND: The conventional thiopurines azathioprine and mercaptopurine are considered maintenance immunosuppressive drugs of choice in the treatment of inflammatory bowel disease (IBD). Unfortunately, treatment is often discontinued because of adverse events (AEs) or refractoriness, retrospectively associated with the high levels of the thiopurine metabolites 6-methylmercaptopurine ribonucleotides (6-MMPR). Patients with a clinically "skewed" thiopurine metabolism may be particularly at risk for therapy failure...
December 2015: Therapeutic Drug Monitoring
Mi-Na Lee, Ben Kang, So Yoon Choi, Mi Jin Kim, Sook Young Woo, Jong-Won Kim, Yon Ho Choe, Soo-Youn Lee
BACKGROUND: Azathioprine (AZA) is commonly used to treat IBD either alone or in combination with mesalazine. However, there are relatively few studies concerning the relationship between AZA dose, thiopurine metabolite levels, and therapeutic response in pediatric patients treated with both AZA and mesalazine. METHODS: We retrospectively investigated the relationship between AZA dose, thiopurine metabolite levels, and therapeutic response in 137 pediatric patients with IBD treated with AZA using multilevel analysis...
May 2015: Inflammatory Bowel Diseases
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