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Salazar J, Riera P, Gordillo J, Altès A, Martínez M, Serès M, Llaó J, Giordano A, Garcia-Planella E. Predictive role of ITPA genetic variants in thiopurine-related myelotoxicity in Crohn's disease patients. THE PHARMACOGENOMICS JOURNAL 2024; 24:20. [PMID: 38906864 DOI: 10.1038/s41397-024-00341-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/04/2023] [Revised: 06/13/2024] [Accepted: 06/17/2024] [Indexed: 06/23/2024]
Abstract
Thiopurines, an effective therapy for Crohn's disease (CD), often lead to adverse events (AEs). Gene polymorphisms affecting thiopurine metabolism may predict AEs. This retrospective study in CD patients (n = 114) with TPMT activity > 5 Units/Red Blood Cells analyzed TPMT (c.238 G > C, c.460 G > A, c.719 A > G), ITPA (c.94 C > A, IVS2 + 21 A > C), and NUDT15 (c.415 C > T) polymorphisms. All patients received azathioprine (median dose 2.2 mg/kg) with 41.2% experiencing AEs, mainly myelotoxicity (28.1%). No NUDT15 polymorphisms were found, 7% had TPMT, and 31.6% had ITPA polymorphisms. AEs led to therapy modifications in 41.2% of patients. Multivariate analysis identified advanced age (OR 1.046, p = 0.007) and ITPA IVS2 + 21 A > C (OR 3.622, p = 0.015) as independent predictors of AEs. IVS2 + 21 A > C was also associated with myelotoxicity (OR 2.863, p = 0.021). These findings suggest that ITPA IVS2 + 21 A > C polymorphism and advanced age predict AEs during thiopurine therapy for CD with intermediate-normal TPMT activity.
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Affiliation(s)
- Juliana Salazar
- Translational Medical Oncology Laboratory, Institut de Recerca Biomèdica Sant Pau (IIB-Sant Pau), Barcelona, Spain
| | - Pau Riera
- Pharmacy Department, Hospital de la Santa Creu I Sant Pau, Barcelona, Spain
- CIBERER U-705, Barcelona, Spain
| | - Jordi Gordillo
- IBD Unit Gastroenterology Department, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain
- Institut de Recerca Biomèdica Sant Pau (IIB-Sant Pau), Barcelona, Spain
| | - Albert Altès
- Hematology Department, Fundació Althaia, Manresa, Barcelona, Spain
| | - Miguel Martínez
- IBD Unit Gastroenterology Department, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain
| | - Montserrat Serès
- Emergency Department, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain
| | - Jordina Llaó
- IBD Unit Gastroenterology Department, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain
| | - Antonio Giordano
- IBD Unit Gastroenterology Department, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain.
- Institut de Recerca Biomèdica Sant Pau (IIB-Sant Pau), Barcelona, Spain.
| | - Esther Garcia-Planella
- IBD Unit Gastroenterology Department, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain
- Institut de Recerca Biomèdica Sant Pau (IIB-Sant Pau), Barcelona, Spain
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Ueda H, Narumi K, Asano S, Saito Y, Furugen A, Kobayashi M. Comparative study on the occurrence of adverse effects in the concomitant use of azathioprine and aldehyde oxidase inhibitors. Expert Opin Drug Saf 2024; 23:89-97. [PMID: 38097359 DOI: 10.1080/14740338.2023.2295976] [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: 06/15/2023] [Accepted: 11/28/2023] [Indexed: 12/19/2023]
Abstract
OBJECTIVES Aldehyde oxidase (AO) is a molybdenum-containing redox enzyme similar to xanthine oxidase that is involved in the thiopurine metabolism. This study investigated the effects of drug-drug interactions (DDIs) between azathioprine (AZA) and AO inhibitors on hematologic and hepatic disorders using the U.S. Food and Drug Administration Adverse Event Reporting System and the Japanese Adverse Drug Event Report database. METHODS The presence of DDI was assessed using the interaction signal scores (ISSs) calculated via the reporting odds ratios and 95% confidence intervals. The study used reports of 'azathioprine' as a suspect drug for adverse effects. AO inhibitors were selected based on previous in vitro reports. RESULTS Some drugs tested positive for ISSs in each database and type of adverse effect (hematologic or hepatic disorder) analysis. Among these drugs, chlorpromazine, clozapine, hydralazine, and quetiapine could inhibit AZA metabolism via AO, given the previously reported clinical blood concentration and inhibitory effects of each drug. CONCLUSION Concomitant use of AO inhibitors increased the signals for AZA-induced adverse effects. To date, no studies have evaluated the clinical importance of AO as a drug-metabolizing enzyme, and further in vitro and clinical research is needed to clarify the contribution of AO to the pharmacokinetics of thiopurines.
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Affiliation(s)
- Hinata Ueda
- Laboratory of Clinical Pharmaceutics & Therapeutics, Division of Pharmasciences, Faculty of Pharmaceutical Sciences, Hokkaido University, Sapporo, Japan
| | - Katsuya Narumi
- Laboratory of Clinical Pharmaceutics & Therapeutics, Division of Pharmasciences, Faculty of Pharmaceutical Sciences, Hokkaido University, Sapporo, Japan
- Education Research Center for Clinical Pharmacy, Faculty of Pharmaceutical Sciences, Hokkaido University, Sapporo, Japan
| | - Shuho Asano
- Laboratory of Clinical Pharmaceutics & Therapeutics, Division of Pharmasciences, Faculty of Pharmaceutical Sciences, Hokkaido University, Sapporo, Japan
| | - Yoshitaka Saito
- Department of Clinical Pharmaceutics & Therapeutics, Faculty of Pharmaceutical Sciences, Hokkaido University of Science, Sapporo, Japan
| | - Ayako Furugen
- Laboratory of Clinical Pharmaceutics & Therapeutics, Division of Pharmasciences, Faculty of Pharmaceutical Sciences, Hokkaido University, Sapporo, Japan
| | - Masaki Kobayashi
- Laboratory of Clinical Pharmaceutics & Therapeutics, Division of Pharmasciences, Faculty of Pharmaceutical Sciences, Hokkaido University, Sapporo, Japan
- Education Research Center for Clinical Pharmacy, Faculty of Pharmaceutical Sciences, Hokkaido University, Sapporo, Japan
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Lukose L, Shantaram PM, Raj A, Nair G, Shaju AM, K Subeesh V. Purine antimetabolites associated Pneumocystis jirovecii pneumonia. Pharmacoepidemiol Drug Saf 2023; 32:1244-1251. [PMID: 37265365 DOI: 10.1002/pds.5647] [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: 11/28/2022] [Revised: 04/06/2023] [Accepted: 05/28/2023] [Indexed: 06/03/2023]
Abstract
PURPOSE To detect the possible safety signal of purine antimetabolites associated with Pneumocystis jirovecii pneumonia through disproportionality analysis in the FDA Adverse Event Reporting System (FAERS) Database. METHODS A case/non-case retrospective disproportionality analysis was performed in the publicly available FAERS database using AERSmine (2004Q1-2021Q3). Four models were developed to explore the signal strength of PAs among different populations with possible confounding factors. Reporting odds ratio (ROR) and Proportional reporting ratio (PRR) was used as the data mining algorithm for the analysis. A value of ROR-1.96SE > 1 and PRR ≥ 2 with an associated X2 value of 4 or more was considered the threshold for a signal. RESULTS A total of 7073 reports associated with Pneumocystis jirovecii pneumonia were present in the database, of which 899 reports were associated with purine antimetabolites. A crude signal strength of ROR 15.76(14.70-16.91) was obtained for purine antimetabolites associated PJP, with the highest signal strength reported with fludarabine and thioguanine [ROR 19.63(17.42-22.13); 19.45(13.21-28.63)]. Stratifying the cases based on autoimmune disorders and the cancer population revealed an ROR of 3.33(2.46-4.50) and 2.93(2.26-3.79) respectively. The highest risk of PJP with use of PAs was observed amongst children with a higher risk of nearly 2 times than the adult population [ROR 11.57(9.16-14.62)]. CONCLUSIONS Our study provided evidence on the occurrence of PJP with the use of purine antimetabolites among the autoimmune and cancer population. We identified signals for PJP with azathioprine, mercaptopurine, thioguanine, cladribine, fludarabine, and clofarabine. More research with a superior epidemiological study design of a defined population is required to validate these findings.
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Affiliation(s)
- Lipin Lukose
- Department of Pharmacy Practice, Manipal College of Pharmaceutical Sciences, Manipal Academy of Higher Education, Manipal, Karnataka, India
| | - Pawar Mansi Shantaram
- Department of Pharmacy Practice, Manipal College of Pharmaceutical Sciences, Manipal Academy of Higher Education, Manipal, Karnataka, India
| | - Alan Raj
- Department of Pharmaceutical Biotechnology, Manipal College of Pharmaceutical Sciences, Manipal Academy of Higher Education, Manipal, Karnataka, India
| | - Gouri Nair
- Faculty of Pharmacy, Department of Pharmacology, MS Ramaiah University of Applied Sciences, Bengaluru, India
| | - Aina M Shaju
- Population Health Sciences Institute, Faculty of Medical Sciences, Newcastle University, Newcastle Upon Tyne, UK
| | - Viswam K Subeesh
- Department of Pharmacy Practice, Manipal College of Pharmaceutical Sciences, Manipal Academy of Higher Education, Manipal, Karnataka, India
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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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Aluko A, Ranganathan P. Pharmacogenetics of Drug Therapies in Rheumatoid Arthritis. Methods Mol Biol 2022; 2547:527-567. [PMID: 36068476 DOI: 10.1007/978-1-0716-2573-6_19] [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] [Indexed: 06/15/2023]
Abstract
Rheumatoid arthritis (RA) is a chronic systemic inflammatory disorder that can lead to severe joint damage and is often associated with a high morbidity and disability. Disease-modifying anti-rheumatic drugs (DMARDs) are the mainstay of treatment in RA. DMARDs not only relieve the clinical signs and symptoms of RA but also inhibit the radiographic progression of disease and reduce the effects of chronic systemic inflammation. Since the introduction of biologic DMARDs in the late 1990s, the therapeutic range of options for the management of RA has significantly expanded. However, patients' response to these agents is not uniform with considerable variability in both efficacy and toxicity. There are no reliable means of predicting an individual patient's response to a given DMARD prior to initiation of therapy. In this chapter, the current published literature on the pharmacogenetics of traditional DMARDS and the newer biologic DMARDs in RA is highlighted. Pharmacogenetics may help individualize drug therapy in patients with RA by providing reliable biomarkers to predict medication toxicity and efficacy.
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Affiliation(s)
- Atinuke Aluko
- Division of Rheumatology, Department of Medicine, Washington University School of Medicine, St. Louis, MO, USA
| | - Prabha Ranganathan
- Division of Rheumatology, Department of Medicine, Washington University School of Medicine, St. Louis, MO, USA.
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Pai AA, Mohan A, Benjamin ESB, Illangeswaran RSS, Xavier Raj I, Janet NB, Arunachalam AK, Kavitha ML, Kulkarni U, Devasia AJ, Fouzia NA, Abraham A, Srivastava A, George B, Mathews V, Korula A, Balasubramanian P. NUDT15 c.415C>T Polymorphism Predicts 6-MP Induced Early Myelotoxicity in Patients with Acute Lymphoblastic Leukemia Undergoing Maintenance Therapy. Pharmgenomics Pers Med 2021; 14:1303-1313. [PMID: 34629890 PMCID: PMC8495143 DOI: 10.2147/pgpm.s325813] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2021] [Accepted: 09/02/2021] [Indexed: 11/25/2022] Open
Abstract
Purpose Severe myelosuppression in patients with acute lymphoblastic leukemia (ALL) undergoing 6-MP-based maintenance therapy is attributed to TPMT gene polymorphisms, which is rare in Asian populations. This study aims to evaluate the role of selected polymorphisms in NUDT15, ITPA, and MRP4 genes in addition to TPMT in predicting 6-MP intolerance during ALL maintenance therapy. Patients and Methods We screened for the presence of NUDT15*3 (c.415 C>T, rs116855232); MRP4 c.2269 C>T (rs3765534), ITPA c.94 C>A (rs1127354) polymorphisms in addition to TPMT *2 (rs1800462), *3A (*3B and *3C; rs1800460 and rs1142345) in ALL patients with documented severe neutropenia (cohort-1; n=42). These polymorphisms were then screened in a prospective cohort of ALL patients (cohort-2; n=133) and compared with 6-MP dose reduction, early/late myelotoxicity. Results Nineteen (45%) patients in cohort-1 and 18 (14%) in cohort-2 had NUDT15 c.415 C>T variant while 4 (3%) patients in cohort-2 had TPMT*3C variant. Five (12%) in cohort-1 and 30 (24%) in cohort-2 had ITPA c.94 C>A variant while 9 (22%) and 15 (12%) had MRP4 c.2269 C>T variant in cohorts-1 and 2, respectively. All in cohort-1 and 36 (27%) in cohort-2 had severe myelotoxicity. Twenty-eight patients (66.6%) in cohort-1 and 40 (30%) patients in cohort-2 had significant 6-MP dose reduction. NUDT15 c.415 C>T variant explained severe myelotoxicity in 63% and 33% in cohort 1 and 2. TPMT*3C and ITPA c.94 C>A variants also explained myelotoxicity in cohort-2 (Median ANC: 376 vs 1014 mm3; p=0.04 and 776 vs 1023 mm3; p=0.04 respectively). NUDT15 c.415 C>T polymorphism explained significant myelotoxicity (507 vs 1298 mm3; p<0.0001) in the multivariate analysis as well (β=−0.314, p<0.0001). Conclusion NUDT15 c.415 C>T (15*3), TPMT*3C, as well as ITPA c.94 C>A and MRP4 c.2269 C>T polymorphisms explain hematotoxicities. Preemptive genotype-based (NUDT15*3, TPMT, ITPA c.94 C>A) 6-MP dosing could improve the outcome after maintenance therapy.
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Affiliation(s)
- Aswin Anand Pai
- Department of Haematology, Christian Medical College, Vellore, Tamilnadu, India
| | - Ajith Mohan
- Department of Haematology, Christian Medical College, Vellore, Tamilnadu, India
| | | | | | - Infencia Xavier Raj
- Department of Haematology, Christian Medical College, Vellore, Tamilnadu, India
| | - Nancy Beryl Janet
- Department of Haematology, Christian Medical College, Vellore, Tamilnadu, India
| | | | - M L Kavitha
- Department of Haematology, Christian Medical College, Vellore, Tamilnadu, India
| | - Uday Kulkarni
- Department of Haematology, Christian Medical College, Vellore, Tamilnadu, India
| | - Anup J Devasia
- Department of Haematology, Christian Medical College, Vellore, Tamilnadu, India
| | - N A Fouzia
- Department of Haematology, Christian Medical College, Vellore, Tamilnadu, India
| | - Aby Abraham
- Department of Haematology, Christian Medical College, Vellore, Tamilnadu, India
| | - Alok Srivastava
- Department of Haematology, Christian Medical College, Vellore, Tamilnadu, India
| | - Biju George
- Department of Haematology, Christian Medical College, Vellore, Tamilnadu, India
| | - Vikram Mathews
- Department of Haematology, Christian Medical College, Vellore, Tamilnadu, India
| | - Anu Korula
- Department of Haematology, Christian Medical College, Vellore, Tamilnadu, India
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Lian X, Li Y, Li L, U K, Wang W, Shi Y, Ma J, Wang H. A novel single-tube multiplex real-time PCR assay for genotyping of thiopurine intolerance-causing variant NUDT15 c.415C>T. Exp Biol Med (Maywood) 2021; 246:1961-1967. [PMID: 34192970 DOI: 10.1177/15353702211026579] [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: 12/04/2022] Open
Abstract
Thiopurines are commonly used in the treatment of acute lymphoblastic leukaemia and autoimmune conditions, can be limited by myelosuppression. The NUDT15 c.415C>T variant is strongly associated with thiopurine-induced myelosuppression, especially in Asians. The purpose of this study was to develop a fast and reliable genotyping method for NUDT15 c.415C>T and investigate the polymorphic distribution among different races in China. A single-tube multiplex real-time PCR assay for NUDT15 c.415C>T genotyping was established using allele-specific TaqMan probes. In 229 samples, the genotyping results obtained through the established method were completely concordant with those obtained by Sanger sequencing. The distributions of NUDT15 c.415C>T among 173 Han Chinese, 48 Miaos, 40 Kazakhs, and 40 Kirghiz were different, with allelic frequencies of 0.06, 0.02, 0.07, and 0, respectively. This method will provide a powerful tool for the implementation of the genotyping-based personalized prescription of thiopurines in clinical settings.
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Affiliation(s)
- Xiaoyun Lian
- Department of Hematology, Shaanxi Provincial Peoples' Hospital, Xi'an 710068, China
| | - Yanwei Li
- The National Engineering Research Center for Miniaturized Detection Systems, Northwest University, Xi'an 710069, China
| | - Lan Li
- Department of Hematology, Shaanxi Provincial Peoples' Hospital, Xi'an 710068, China
| | - Kaicheng U
- American Heritage School, Plantation, FL 33325, USA
| | - Wenxia Wang
- The National Engineering Research Center for Miniaturized Detection Systems, Northwest University, Xi'an 710069, China
| | - Yinmin Shi
- The National Engineering Research Center for Miniaturized Detection Systems, Northwest University, Xi'an 710069, China
| | - Jiying Ma
- The National Engineering Research Center for Miniaturized Detection Systems, Northwest University, Xi'an 710069, China
| | - Huijuan Wang
- The National Engineering Research Center for Miniaturized Detection Systems, Northwest University, Xi'an 710069, China
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Abstract
Patients with inflammatory bowel disease (IBD) show large variability in disease course, and also treatment response. The variability in treatment response has led to many initiatives in search of genetic markers to optimize treatment and avoid severe side effects. This has been very successful for thiopurines, one of the drugs used to induce and maintain remission in IBD. However, for the newer treatment options for IBD, like biologicals, the search for genetic predictors has not yielded any candidate biomarkers with clinical utility. In this review, a summary of recent advances in pharmacogenetics focusing on thiopurines and anti-TNF agents is given.
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Affiliation(s)
- Bianca Jc van den Bosch
- Deparment of Clinical Genetics, Maastricht University Medical Center, P.O. Box 5800, 6202 AZ Maastricht, The Netherlands
| | - Marieke Jh Coenen
- Department of Human Genetics, Radboud Institute for Health Sciences, Radboud University Medical Center, P.O. Box 9101, 6500HB, Nijmegen, The Netherlands
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Maamari D, El-Khoury H, Saifi O, Muwakkit SA, Zgheib NK. Implementation of Pharmacogenetics to Individualize Treatment Regimens for Children with Acute Lymphoblastic Leukemia. Pharmgenomics Pers Med 2020; 13:295-317. [PMID: 32848445 PMCID: PMC7429230 DOI: 10.2147/pgpm.s239602] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Accepted: 07/20/2020] [Indexed: 12/28/2022] Open
Abstract
Despite major advances in the management and high cure rates of childhood acute lymphoblastic leukemia (ALL), patients still suffer from many drug-induced toxicities, sometimes necessitating dose reduction, or halting of cytotoxic drugs with a secondary risk of disease relapse. In addition, investigators have noted significant inter-individual variability in drug toxicities and disease outcomes, hence the role of pharmacogenetics (PGx) in elucidating genetic polymorphisms in candidate genes for the optimization of disease management. In this review, we present the PGx data in association with main toxicities seen in children treated for ALL in addition to efficacy, with a focus on the most plausible germline PGx variants. We then follow with a summary of the highest evidence drug-gene annotations with suggestions to move forward in implementing preemptive PGx for the individualization of treatment regimens for children with ALL.
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Affiliation(s)
- Dimitri Maamari
- Faculty of Medicine, American University of Beirut, Beirut, Lebanon
| | - Habib El-Khoury
- Faculty of Medicine, American University of Beirut, Beirut, Lebanon
| | - Omran Saifi
- Faculty of Medicine, American University of Beirut, Beirut, Lebanon
| | - Samar A Muwakkit
- Department of Pediatrics and Adolescent Medicine, American University of Beirut Medical Center, Beirut, Lebanon
| | - Nathalie K Zgheib
- Department of Pharmacology and Toxicology, American University of Beirut, Faculty of Medicine, Beirut, Lebanon
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van Gennep S, Konté K, Meijer B, Heymans MW, D'Haens GR, Löwenberg M, de Boer NKH. Systematic review with meta-analysis: risk factors for thiopurine-induced leukopenia in IBD. Aliment Pharmacol Ther 2019; 50:484-506. [PMID: 31342537 DOI: 10.1111/apt.15403] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/31/2018] [Revised: 02/02/2019] [Accepted: 06/16/2019] [Indexed: 12/11/2022]
Abstract
BACKGROUND Thiopurine-induced leukopenia, a frequently observed and potentially life-threatening adverse event, complicates the clinical management of IBD patients. AIM To assess risk factors for thiopurine-induced leukopenia in IBD. METHODS MEDLINE, EMBASE, BIOSIS and Cochrane library were searched for studies reporting at least one risk factor for thiopurine-induced leukopenia. Pooled odds ratio (OR) was calculated for each potential risk factor using a random effects model. Studies that were not eligible for meta-analysis were described qualitatively. RESULTS Seventy articles were included, 34 (11 229 patients) were included in meta-analyses. A significantly higher thiopurine-induced leukopenia risk was found for TPMT (OR 3.9, 95% [CI] 2.5-6.1) and for NUDT15 R139C (OR 6.9, 95% CI 5.2-9.1), G52A (OR 3.2, 95% CI 1.3-7.9) and 36_37ins/delGGAGTC variant carriers (OR 5.6, 95% CI 2.8-11.4). A potential association between high 6-thioguanine nucleotides (6-TGN) or 6-methylmercaptopurine (6-MMP) levels and leukopenia was observed, since most studies reported higher metabolite levels in leukopenic patients (6-TGN: 204-308 (Lennard method) and 397 (Dervieux method), 6-MMP: 4020-10 450 pmol/8 x 108 RBC) compared to controls (6-TGN: 170-212 (Lennard method) and 269 (Dervieux method), 6-MMP: 1025-4550 pmol/8 x 108 RBC). CONCLUSIONS TPMT and NUDT15 variants predict thiopurine-induced leukopenia. High 6-TGN and 6-MMP levels might induce leukopenia, although exact cut-off values remain unclear. Potential preventive measures to reduce the risk of thiopurine-induced leukopenia include pre-treatment TPMT and NUDT15 genotyping. Routine thiopurine metabolite measurement might be efficient, yet cut-off levels must be validated in advance.
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Affiliation(s)
- Sara van Gennep
- Department of Gastroenterology and Hepatology, Amsterdam Gastroenterology and Metabolism Research Institute, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
| | - Kadère Konté
- Department of Gastroenterology and Hepatology, Amsterdam Gastroenterology and Metabolism Research Institute, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
| | - Berrie Meijer
- Department of Gastroenterology and Hepatology, Amsterdam Gastroenterology and Metabolism Research Institute, Amsterdam UMC, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
| | - Martijn W Heymans
- Department of Clinical Epidemiology and Biostatistics, Amsterdam UMC, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
| | - Geert R D'Haens
- Department of Gastroenterology and Hepatology, Amsterdam Gastroenterology and Metabolism Research Institute, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
| | - Mark Löwenberg
- Department of Gastroenterology and Hepatology, Amsterdam Gastroenterology and Metabolism Research Institute, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
| | - Nanne K H de Boer
- Department of Gastroenterology and Hepatology, Amsterdam Gastroenterology and Metabolism Research Institute, Amsterdam UMC, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
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Sluiter RL, van Marrewijk C, de Jong D, Scheffer H, Guchelaar HJ, Derijks L, Wong DR, Hooymans P, Vermeulen SH, Verbeek ALM, Franke B, van der Wilt GJ, Kievit W, Coenen MJH. Genotype-Guided Thiopurine Dosing Does not Lead to Additional Costs in Patients With Inflammatory Bowel Disease. J Crohns Colitis 2019; 13:838-845. [PMID: 30698675 PMCID: PMC7142326 DOI: 10.1093/ecco-jcc/jjz009] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
BACKGROUND AND AIMS Decreased thiopurine S-methyltransferase [TPMT] enzyme activity increases the risk of haematological adverse drug reactions [ADRs] in patients treated with thiopurines. Clinical studies have shown that in patients with inflammatory bowel disease [IBD], pharmacogenetic TPMT-guided thiopurine treatment reduces this risk of ADRs. The aim of this study was to investigate whether this intervention impacts on healthcare costs and/or quality of life. METHODS An a priori defined cost-effectiveness analysis was conducted in the Thiopurine response Optimization by Pharmacogenetic testing in Inflammatory bowel disease Clinics [TOPIC] trial, a randomized controlled trial performed in 30 Dutch hospitals. Patients diagnosed with IBD [age ≥18 years] were randomly assigned to the intervention [i.e. pre-treatment genotyping] or control group. Total costs in terms of volumes of care, and effects in quality-adjusted life years [QALYs], based on EuroQol-5D3L utility scores, were measured for 20 weeks. Mean incremental cost savings and QALYs with confidence intervals were calculated using non-parametric bootstrapping with 1000 replications. RESULTS The intervention group consisted of 381 patients and the control group 347 patients. The mean incremental cost savings were €52 per patient [95% percentiles -682, 569]. Mean incremental QALYs were 0.001 [95% percentiles -0.009, 0.010]. Sensitivity analysis showed that the results were robust for potential change in costs of screening, costs of biologicals and costs associated with productivity loss. CONCLUSIONS Genotype-guided thiopurine treatment in IBD patients reduced the risk of ADRs among patients carrying a TPMT variant, without increasing overall healthcare costs and resulting in comparable quality of life, as compared to standard treatment.
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Affiliation(s)
- Reinier L Sluiter
- Department for Health Evidence, Radboud Institute for Health Sciences, Radboud University Medical Center, Nijmegen, The Netherlands,Corresponding author: Reinier Luuk (Rene) Sluiter, Geert Grooteplein 21 (route 135), 6525 EZ Nijmegen, The Netherlands. Tel: +31 (0)24 36 55747; Fax: +31 (0)24 36 13505;
| | - Corine van Marrewijk
- Department of Human Genetics, Radboud Institute for Health Sciences, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Dirk de Jong
- Department of Gastroenterology, Radboud Institute Radboud Institute for Health Sciences, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Hans Scheffer
- Department of Human Genetics, Radboud Institute for Health Sciences, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Henk-Jan Guchelaar
- Department of Clinical Pharmacy and Toxicology, Leiden University Medical Center, Leiden, The Netherlands
| | - Luc Derijks
- Department of Clinical Pharmacy, Máxima Medical Center, Veldhoven, The Netherlands
| | - Dennis R Wong
- Department of Clinical Pharmacy, Pharmacology and Toxicology, Zuyderland Medical Center, Sittard-Geleen, The Netherlands
| | - Piet Hooymans
- Department of Clinical Pharmacy, Pharmacology and Toxicology, Zuyderland Medical Center, Sittard-Geleen, The Netherlands
| | - Sita H Vermeulen
- Department for Health Evidence, Radboud Institute for Health Sciences, Radboud University Medical Center, Nijmegen, The Netherlands,Department of Human Genetics, Radboud Institute for Health Sciences, Radboud University Medical Center, Nijmegen, The Netherlands
| | - André L M Verbeek
- Department for Health Evidence, Radboud Institute for Health Sciences, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Barbara Franke
- Department of Human Genetics, Radboud Institute for Health Sciences, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Gert Jan van der Wilt
- Department for Health Evidence, Radboud Institute for Health Sciences, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Wietske Kievit
- Department for Health Evidence, Radboud Institute for Health Sciences, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Marieke J H Coenen
- Department of Human Genetics, Radboud Institute for Health Sciences, Radboud University Medical Center, Nijmegen, The Netherlands
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13
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Relling MV, Schwab M, Whirl-Carrillo M, Suarez-Kurtz G, Pui CH, Stein CM, Moyer AM, Evans WE, Klein TE, Antillon-Klussmann FG, Caudle KE, Kato M, Yeoh AEJ, Schmiegelow K, Yang JJ. Clinical Pharmacogenetics Implementation Consortium Guideline for Thiopurine Dosing Based on TPMT and NUDT15 Genotypes: 2018 Update. Clin Pharmacol Ther 2019; 105:1095-1105. [PMID: 30447069 DOI: 10.1002/cpt.1304] [Citation(s) in RCA: 374] [Impact Index Per Article: 74.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2018] [Accepted: 10/24/2018] [Indexed: 12/14/2022]
Abstract
Thiopurine methyltransferase (TPMT) activity exhibits a monogenic codominant inheritance and catabolizes thiopurines. TPMT variant alleles are associated with low enzyme activity and pronounced pharmacologic effects of thiopurines. Loss-of-function alleles in the NUDT15 gene are common in Asians and Hispanics and reduce the degradation of active thiopurine nucleotide metabolites, also predisposing to myelosuppression. We provide recommendations for adjusting starting doses of azathioprine, mercaptopurine, and thioguanine based on TPMT and NUDT15 genotypes (updates on www.cpicpgx.org).
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Affiliation(s)
- Mary V Relling
- Department of Pharmaceutical Sciences, St. Jude Children's Research Hospital, Memphis, Tennessee, USA
| | - Matthias Schwab
- Dr. Margarete Fischer-Bosch Institute of Clinical Pharmacology, Stuttgart, Germany
- Department of Clinical Pharmacology, Institute of Experimental and Clinical Pharmacology and Toxicology, University Hospital, Tuebingen, Germany
- Department of Pharmacy and Biochemistry, University of Tuebingen, Tuebingen, Germany
| | | | - Guilherme Suarez-Kurtz
- Instituto Nacional de Câncer, Rio de Janeiro, Brazil Pharmacogenomics Network, Rio de Janeiro, Brazil
| | - Ching-Hon Pui
- Department of Oncology, St. Jude Children's Research Hospital, Memphis, Tennessee, USA
| | - Charles M Stein
- Division of Clinical Pharmacology, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
| | - Ann M Moyer
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota, USA
| | - William E Evans
- Department of Pharmaceutical Sciences, St. Jude Children's Research Hospital, Memphis, Tennessee, USA
| | - Teri E Klein
- Department of Pharmacy and Biochemistry, University of Tuebingen, Tuebingen, Germany
| | | | - Kelly E Caudle
- Department of Pharmaceutical Sciences, St. Jude Children's Research Hospital, Memphis, Tennessee, USA
| | - Motohiro Kato
- Department of Pediatric Hematology and Oncology Research, National Center for Child Health and Development, Tokyo, Japan
| | - Allen E J Yeoh
- National University Health System, National University Cancer Institute, Singapore
- Viva University Children's Cancer Centre, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Kjeld Schmiegelow
- Department of Paediatrics and Adolescent Medicine, Rigshospitalet University Hospital, Copenhagen, Denmark
- Institute of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark
| | - Jun J Yang
- Department of Pharmaceutical Sciences, St. Jude Children's Research Hospital, Memphis, Tennessee, USA
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14
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Hanauer SB, Sandborn WJ, Lichtenstein GR. Evolving Considerations for Thiopurine Therapy for Inflammatory Bowel Diseases-A Clinical Practice Update: Commentary. Gastroenterology 2019; 156:36-42. [PMID: 30195449 DOI: 10.1053/j.gastro.2018.08.043] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/12/2017] [Revised: 07/29/2018] [Accepted: 08/06/2018] [Indexed: 12/17/2022]
Abstract
Thiopurines (azathioprine, mercaptopurine, thioguanine) and methotrexate are widely used in a variety of clinical management scenarios for ulcerative colitis and Crohn's disease. With the introduction of biologic therapies over the last 2 decades, controversies have emerged as to how these immunomodulators should be used in clinical practice, either alone as monotherapies or in combination with biologic therapies. Here, we provide a summary of evidence and our interpretations regarding how physicians can or should incorporate these agents into clinical practice. We have organized the review into sections regarding their utility as monotherapy or as combination therapy with biologics and safety considerations. Clinical pharmacologic considerations are important regarding both efficacy and safety.
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Affiliation(s)
- Stephen B Hanauer
- Digestive Health Center, Northwestern University Feinberg School of Medicine, Chicago, Illinois
| | - William J Sandborn
- Division of Gastroenterology, University of California, San Diego, La Jolla, California
| | - Gary R Lichtenstein
- Division of Gastroenterology, Perelman School of Medicine of the University of Pennsylvania, Philadelphia, Pennsylvania.
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15
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Baghbanian SM, Asgari N, Sahraian MA, Moghadasi AN. A comparison of pediatric and adult neuromyelitis optica spectrum disorders: A review of clinical manifestation, diagnosis, and treatment. J Neurol Sci 2018; 388:222-231. [DOI: 10.1016/j.jns.2018.02.028] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2017] [Revised: 12/19/2017] [Accepted: 02/16/2018] [Indexed: 12/12/2022]
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16
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Hessels AC, Rutgers A, Sanders JSF, Stegeman CA. Thiopurine methyltransferase genotype and activity cannot predict outcomes of azathioprine maintenance therapy for antineutrophil cytoplasmic antibody associated vasculitis: A retrospective cohort study. PLoS One 2018; 13:e0195524. [PMID: 29630648 PMCID: PMC5890988 DOI: 10.1371/journal.pone.0195524] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2017] [Accepted: 03/23/2018] [Indexed: 11/25/2022] Open
Abstract
Objective Azathioprine is a widely used immunosuppressive drug. Genetic polymorphisms and activity of the enzyme thiopurine methyltransferase (TPMT) have been associated with azathioprine efficacy and toxicity in several populations. We investigated whether these associations also exist for ANCA associated vasculitis (AAV) patients, who receive azathioprine maintenance therapy after remission induction with cyclophosphamide. Methods 207 AAV patients treated with cyclophosphamide induction and azathioprine maintenance therapy were included and followed for 60 months. TPMT genotype and tertiles of TPMT activity were compared to relapse free survival and occurrence of adverse events, particularly leukopenia. Multivariable regression was performed to account for confounders. Results In univariable analysis, relapse free survival was not significantly associated with TPMT genotype (P = 0.41) or TPMT activity (P = 0.07), although it tended to be longer in lower tertiles of TPMT activity. There was no significant association of TPMT genotype and activity with occurrence of any adverse event. In multiple regression, leukocyte counts at the end of cyclophosphamide induction were related to risk of leukopenia during azathioprine therapy [P<0.001; OR 0.54 (95% CI 0.43–0.68)] and risk of relapse during follow-up [P = 0.001; HR 1.17 (95% CI 1.07–1.29)] irrespective of TMPT genotype or activity. Conclusion TPMT genotype and activity were not independent predictors of relapse, and could not predict leukopenia or other adverse effects from azathioprine. Leukocyte counts after cyclophosphamide induction were related to both outcomes, implying a greater influence of cyclophosphamide response compared to azathioprine and TPMT in AAV patients.
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Affiliation(s)
- Arno C. Hessels
- Department of Internal Medicine, Division of Nephrology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
- * E-mail:
| | - Abraham Rutgers
- Department of Rheumatology and Clinical Immunology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Jan Stephan F. Sanders
- Department of Internal Medicine, Division of Nephrology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Coen A. Stegeman
- Department of Internal Medicine, Division of Nephrology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
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Kim GJ, Lee SY, Park JH, Ryu BY, Kim JH. Role of Preemptive Genotyping in Preventing Serious Adverse Drug Events in South Korean Patients. Drug Saf 2017; 40:65-80. [PMID: 27638658 DOI: 10.1007/s40264-016-0454-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
INTRODUCTION Preemptive and multi-variant genotyping is suggested to improve the safety of patient drug therapy. The number of South Koreans who would benefit from this approach is unknown. OBJECTIVE We aimed to quantify the number of patients who may experience serious adverse drug events (ADEs) due to high-risk pharmacogenetic variants and who may benefit from preemptive genotyping. METHODS The health claims dataset of the Korean Health Insurance Review and Assessment service for 3 % of the South Korean population for year 2011 was used to calculate the number of patients exposed to 84 drugs covered by National Health Insurance with pharmacogenomic biomarkers. The product of ADE risk-conferring genotype prevalence, ADE prevalence rates, and genotype effect sizes in South Koreans or East Asians derived from published literature and the 1000 Genomes Project, and the drug exposure data were solved to estimate the number of South Koreans in whom preemptive genotyping may prevent serious ADEs. RESULTS Among 1,341,077 patients in the dataset with prescriptions, 47.4 % were prescribed a drug whose response was affected by genetic variants and 31.9 % were prescribed at least one drug with serious ADEs modulated by these variants. Without genetic testing, the number of South Korean patients predicted to experience serious ADEs due to their higher ADE risk genotypes was estimated at 729. Extrapolating this to the total South Korean population indicated that approximately 24,300 patients in 2011 might have benefitted from preemptive genotyping. CONCLUSIONS This study quantified the number of South Korean patients predicted to have serious ADEs and demonstrated the need for preemptive genotyping to assist safer drug therapy in South Korea.
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Affiliation(s)
- Grace Juyun Kim
- Seoul National University Biomedical Informatics (SNUBI), 28 Yongon-dong, Chongno-gu, Seoul, 110799, South Korea
| | - Soo Youn Lee
- Interdisciplinary Program in Bioinformatics, Seoul National University College of Natural Sciences, 28 Yongon-dong, Chongno-gu, Seoul, 110799, South Korea
| | - Ji Hye Park
- Interdisciplinary Program in Bioinformatics, Seoul National University College of Natural Sciences, 28 Yongon-dong, Chongno-gu, Seoul, 110799, South Korea
| | - Brian Y Ryu
- Interdisciplinary Program in Bioinformatics, Seoul National University College of Natural Sciences, 28 Yongon-dong, Chongno-gu, Seoul, 110799, South Korea
| | - Ju Han Kim
- Seoul National University Biomedical Informatics (SNUBI), 28 Yongon-dong, Chongno-gu, Seoul, 110799, South Korea. .,Division of Biomedical Informatics, Systems Biomedical Informatics National Core Research Center (SBI-NCRC), Seoul National University College of Medicine, 28 Yongon-dong, Chongno-gu, Seoul, 110799, South Korea.
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18
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Broekman MMTJ, Coenen MJH, Wanten GJ, van Marrewijk CJ, Klungel OH, Verbeek ALM, Hooymans PM, Guchelaar H, Scheffer H, Derijks LJJ, Wong DR, de Jong DJ. Risk factors for thiopurine-induced myelosuppression and infections in inflammatory bowel disease patients with a normal TPMT genotype. Aliment Pharmacol Ther 2017; 46:953-963. [PMID: 28914446 PMCID: PMC5698717 DOI: 10.1111/apt.14323] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/13/2017] [Revised: 07/09/2017] [Accepted: 08/25/2017] [Indexed: 12/21/2022]
Abstract
BACKGROUND Leucopenia is a common side effect in patients treated with thiopurines. Variants in the thiopurine S-methyltransferase (TPMT) gene are the best-known risk factor, but only explain up to 25% of leucopenia cases. AIM To identify the clinical risk factors for thiopurine-induced leucopenia in patients without a common TPMT variant, and explore if these patients are at increased risk for infections. METHODS Post hoc analysis of the Thiopurine response Optimisation by Pharmacogenetic testing in Inflammatory bowel disease Clinics (TOPIC) trial. For this analysis, patients without a variant in TPMT (*2, *3A or*3C) were included. Uni- and multivariate Cox-proportional hazard models were used to identify risk factors for leucopenia and infections. Leucopenia was defined as a white blood cell (WBC) count <3.0 × 109 /L and infections were classified according to the Common Terminology Criteria for Adverse Events. RESULTS Sixty hundred and ninety-five patients (90.6%) included in the TOPIC-trial had no variant in TPMT, of which 45 (6.5%) developed leucopenia. Median time to leucopenia was 56 (29-112) days. Multivariate analysis showed that use of mercaptopurine compared to azathioprine was associated with leucopenia (hazard ratio [HR] 2.61 [95% CIs, 1.39-4.88; P < .01]) and a higher baseline WBC count was protective (HR 0.80 [95% CIs, 0.71-0.89; P < .01]). Risk factors for infections were older age (per 10 year; HR 2.07 [95% CIs, 1.18-3.63; P = .01]) and concomitant use of biologic drugs (HR 2.15 [95% CIs, 1.14-4.07; P = .02]). CONCLUSIONS Low baseline WBC count and mercaptopurine, due to a relatively higher dose, were risk factors for thiopurine-induced leucopenia in patients without a TPMT variant.
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Affiliation(s)
- M. M. T. J. Broekman
- Department of GastroenterologyRadboud Institute for Molecular Life SciencesRadboud University Medical CenterNijmegenThe Netherlands
| | - M. J. H. Coenen
- Department of Human GeneticsRadboud Institute for Health SciencesRadboud University Medical CenterNijmegenThe Netherlands
| | - G. J. Wanten
- Department of GastroenterologyRadboud Institute for Molecular Life SciencesRadboud University Medical CenterNijmegenThe Netherlands
| | - C. J. van Marrewijk
- Department of Human GeneticsRadboud Institute for Health SciencesRadboud University Medical CenterNijmegenThe Netherlands
| | - O. H. Klungel
- Department of Pharmacoepidemiology and PharmacotherapyUtrecht UniversityUtrechtThe Netherlands
| | - A. L. M. Verbeek
- Department for Health EvidenceRadboud University Medical CenterNijmegenThe Netherlands
| | - P. M. Hooymans
- Department of Clinical Pharmacy, Pharmacology and ToxicologyZuyderland Medical CenterSittard‐GeleenThe Netherlands
| | - H.‐J. Guchelaar
- Department of Clinical Pharmacy and ToxicologyLeiden University Medical CenterLeidenThe Netherlands
| | - H. Scheffer
- Department of Human GeneticsRadboud Institute for Health SciencesRadboud University Medical CenterNijmegenThe Netherlands
| | - L. J. J. Derijks
- Department of Clinical PharmacyMáxima Medical CenterVeldhovenThe Netherlands
| | - D. R. Wong
- Department of Clinical Pharmacy, Pharmacology and ToxicologyZuyderland Medical CenterSittard‐GeleenThe Netherlands
| | - D. J. de Jong
- Department of GastroenterologyRadboud Institute for Molecular Life SciencesRadboud University Medical CenterNijmegenThe Netherlands
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Prevalence of thiopurine S-methyltransferase gene polymorphisms in patients with inflammatory bowel disease from the island of Crete, Greece. Eur J Gastroenterol Hepatol 2017; 29:1284-1289. [PMID: 28857898 DOI: 10.1097/meg.0000000000000947] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/10/2022]
Abstract
BACKGROUND There is evidence that genotyping for the thiopurine S-methyltransferase (TPMT) gene variants is useful for the prediction of response to thiopurine analogs (azathioprine and 6-mercaptopurine) in patients with inflammatory bowel disease (IBD). The aim of the present study was to determine the prevalence of TPMT gene polymorphisms in a genetic homogenous population of IBD patients in Crete and to correlate the results with adverse reactions to thiopurine drugs. PATIENTS AND METHODS Genotyping for the most common TPMT variants TPMT*2, TPMT*3A, TPMT3*C, and TPMT*3B was performed using the PCR-restriction fragment length polymorphism method in 223 consecutive IBD patients and 119 age-matched and sex-matched healthy controls. The hospital medical records were reviewed for thiopurine use in these patients and related adverse events. RESULTS The prevalence of TPMT variants TPMT*2, TPMT*3A, TPMT*3B, and TPMT*3C was 1.8, 2.7, 1.3, and 1.8%, respectively. The G238C mutation was detected in four (1.8%) out of 223 patients, three (1.3%) patients were carriers of the G460A mutation, four (1.8%) of the A719G mutation, and six (2.7%) of both G460A and A719G mutations. In healthy controls, only one (0.8%) carried both the G460A and the A719G mutation, whereas TPMT*2, TPMT*3C, and TPMT*3B were not detected. None of the genotypes was homozygous. A statistically significant correlation between the presence of the G460A mutation and the development of leucopenia after the administration of thiopurines was observed (P=0.048). CONCLUSION This study showed a lower frequency of total TPMT variants and a higher frequency of TPMT*3B in Cretan IBD patients compared with other Caucasian populations. The presence of the G460A mutation is associated with the development of leukopenia.
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20
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Sahraian MA, Moghadasi AN, Azimi AR, Asgari N, H Akhoundi F, Abolfazli R, Alaie S, Ashtari F, Ayromlou H, Baghbanian SM, Moghadam NB, Fatehi F, Foroughipour M, Langroodi HG, Majdinasab N, Nickseresht A, Nourian A, Shaygannejad V, Torabi HR. Diagnosis and management of Neuromyelitis Optica Spectrum Disorder (NMOSD) in Iran: A consensus guideline and recommendations. Mult Scler Relat Disord 2017; 18:144-151. [PMID: 29141797 DOI: 10.1016/j.msard.2017.09.015] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2017] [Revised: 09/11/2017] [Accepted: 09/18/2017] [Indexed: 11/25/2022]
Abstract
Neuromyelitis Optica Spectrum Disorder (NMOSD) is a relapsing neuro inflammatory disease of the central nervous system that typically presents with optic neuritis or myelitis and may cause severe disability. The diagnostic criteria have been updated and several immunosuppressive agents have been demonstrated to prevent acute exacerbations. As the disease rarely develops in a progressive course, management of acute attacks and proper prevention of exacerbations may change the long term out-come and prevent future disability. Consensus recommendations and guidelines will help the physicians to improve their practice and unify the treatment approaches in different communities. In order to develop a national consensus and recommendations for the diagnosis and management of NMOSD in Iran, a group of neurologists with long term experience in management of NMOSD were gathered to develop this consensus based on available national and international data. The primary draft was prepared and discussed to suggest the most appropriate treatment for these patients. We propose strategies for early diagnosis and treatment for prevention of relapses and minimizing consequences of attacks as a primary therapeutic goal. Attacks are currently treated with intravenous corticosteroids and, in refractory cases, with plasma exchange. All participants agreed on preventive treatment with currently available immunosuppressive agents such as azothioprin, rituximab and mycofenolate mofetil based on previous positive data in NMOSD in order to reduce attack frequency. The current consensus reviews the previous data and provides the clinicians with practical recommendations and advices for the diagnosis and management of NMOSD based on scientific data and clinical experience.
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Affiliation(s)
- Mohammad Ali Sahraian
- MS Research Center, Neuroscience Institute, Tehran University of Medical Sciences, Iran; Iranian Center for Neurological Research, Neuroscience Institute, Tehran University of Medical Sciences, Iran.
| | | | - Amir Reza Azimi
- MS Research Center, Neuroscience Institute, Tehran University of Medical Sciences, Iran; Iranian Center for Neurological Research, Neuroscience Institute, Tehran University of Medical Sciences, Iran
| | - Nasrin Asgari
- Institutes of Regional Health Research and Molecular Medicine, University of Southern Denmark, Denmark
| | - Fahimeh H Akhoundi
- Department of Neurology, Firozgar Hospital, Iran University of Medical Sciences, Iran
| | - Roya Abolfazli
- Department of Neurology, Amiralam Hospital, Tehran University of Medical Sciences, Iran
| | | | - Fereshteh Ashtari
- Department of Neurology, Kashani Hospital, Isfahan University of Medical Sciences, Iran; Isfahan neurosciences research center, Alzahra Hospital, Department of Neurology, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Hormoz Ayromlou
- Department of Neurology, Faculty of Medicine, Tabriz University of Medical Sciences, Iran
| | | | - Nahid Beladi Moghadam
- Department of Neurology, Imam Hossein Hospital, Shahid Beheshti University of Medical Sciences, Iran
| | - Farzad Fatehi
- Iranian Center for Neurological Research, Neuroscience Institute, Tehran University of Medical Sciences, Iran; Department of Neurology, Shariati Hospital, Tehran University of Medical Sciences, Iran
| | - Mohsen Foroughipour
- Department of Neurology, Faculty of Medicine, Mashhad University of Medical Sciences, Iran
| | | | - Nastaran Majdinasab
- Department of Neurology, Golestan Hospital, Ahwaz University of Medical Sciences, Iran
| | - Alireza Nickseresht
- Department of Neurology, Namazi Hospital, Shiraz University of Medical Sciences, Iran
| | - Abbas Nourian
- Islamic Azad University, Faculty of Medicine, Khorasan Razavi Branch, Iran
| | - Vahid Shaygannejad
- Isfahan neurosciences research center, Alzahra Hospital, Department of Neurology, Isfahan University of Medical Sciences, Isfahan, Iran
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Dart RJ, Irving PM. Optimising use of thiopurines in inflammatory bowel disease. Expert Rev Clin Immunol 2017; 13:877-888. [DOI: 10.1080/1744666x.2017.1351298] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Robin J. Dart
- IBD Centre, Department of Gastroenterology, St Thomas’ Hospital, London, UK
- Immunosurveillance Lab, Francis Crick Institute, London, UK
- Immunobiology, DIIID, King’s College London, Guy’s Hospital, London, UK
| | - Peter M. Irving
- IBD Centre, Department of Gastroenterology, St Thomas’ Hospital, London, UK
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Meijer B, Kreijne JE, van Moorsel SAW, Derijks LJJ, Bouma G, Mulder CJJ, Wong DR, van der Woude CJ, van Bodegraven AA, de Boer NKH. 6-methylmercaptopurine-induced leukocytopenia during thiopurine therapy in inflammatory bowel disease patients. J Gastroenterol Hepatol 2017; 32:1183-1190. [PMID: 27859568 DOI: 10.1111/jgh.13656] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/07/2016] [Revised: 11/07/2016] [Accepted: 11/11/2016] [Indexed: 01/15/2023]
Abstract
BACKGROUND AND AIM Thiopurines have a favorable benefit-risk ratio in the treatment of inflammatory bowel disease. A feared adverse event of thiopurine therapy is myelotoxicity, mostly occurring due to toxic concentrations of the pharmacologically active metabolites 6-thioguaninenucleotides. In oncology, myelosuppression has also been associated with elevated 6-methylmercaptopurine (6-MMP). In this case series, we provide a detailed overview of 6-MMP-induced myelotoxicity in inflammatory bowel disease patients. METHODS We retrospectively scrutinized pharmacological laboratory databases of five participating centers over a 5-year period. Patients with leukocytopenia at time of elevated 6-MMP levels (>5700 pmol/8 × 108 red blood cells) were included for detailed chart review. RESULTS In this case series, we describe demographic, clinical, and pharmacological aspects of 24 cases of 6-MMP-induced myelotoxicity on weight-based thiopurine therapy with a median steady-state 6-MMP level of 14 500 pmol/8 × 108 red blood cells (range 6600-48 000). All patients developed leukocytopenia (white blood cell count 2.7 ± 0.9 × 109 /L) after a median period of 11 weeks after initiation of thiopurine therapy (interquartile range 6-46 weeks). Eighteen patients (75%) developed concurrent anemia (median hemoglobin concentration 6.9 × 109 /L), and four patients developed concurrent thrombocytopenia (median platelet count 104 × 109 /L). Leukocytopenia resolved in 20 patients (83%) within 4 weeks upon altered thiopurine treatment regimen, and white blood cell count was increasing, but not yet normalized, in the remaining four patients. CONCLUSION We observed that thiopurine-induced myelotoxicity also occurs because of (extremely) high 6-MMP concentrations in patients with a skewed thiopurine metabolism. Continued treatment with adapted thiopurine therapy was successful in almost all patients.
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Affiliation(s)
- Berrie Meijer
- Department of Gastroenterology and Hepatology, VU University Medical Center, Amsterdam, The Netherlands
| | - Joany E Kreijne
- Department of Gastroenterology and Hepatology, Erasmus Medical Center, Rotterdam, The Netherlands
| | - Sofia A W van Moorsel
- Department of Clinical Pharmacy, Pharmacology and Toxicology, Zuyderland Medical Center, Heerlen-Sittard-Geleen, The Netherlands.,Department of Clinical Pharmacy, Maastricht University Medical Center, Maastricht, The Netherlands
| | - Luc J J Derijks
- Department of Clinical Pharmacy, Máxima Medical Center, Veldhoven, The Netherlands
| | - Gerd Bouma
- Department of Gastroenterology and Hepatology, VU University Medical Center, Amsterdam, The Netherlands
| | - Chris J J Mulder
- Department of Gastroenterology and Hepatology, VU University Medical Center, Amsterdam, The Netherlands
| | - Dennis R Wong
- Department of Clinical Pharmacy, Pharmacology and Toxicology, Zuyderland Medical Center, Heerlen-Sittard-Geleen, The Netherlands
| | - C Janneke van der Woude
- Department of Gastroenterology and Hepatology, Erasmus Medical Center, Rotterdam, The Netherlands
| | - Adriaan A van Bodegraven
- Department of Gastroenterology and Hepatology, VU University Medical Center, Amsterdam, The Netherlands.,Department of Gastroenterology, Geriatrics, Internal and Intensive Care Medicine (Co-MIK), Zuyderland Medical Center, Heerlen-Sittard-Geleen, The Netherlands
| | - Nanne K H de Boer
- Department of Gastroenterology and Hepatology, VU University Medical Center, Amsterdam, The Netherlands
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Abaji R, Krajinovic M. Thiopurine S-methyltransferase polymorphisms in acute lymphoblastic leukemia, inflammatory bowel disease and autoimmune disorders: influence on treatment response. PHARMACOGENOMICS & PERSONALIZED MEDICINE 2017; 10:143-156. [PMID: 28507448 PMCID: PMC5428801 DOI: 10.2147/pgpm.s108123] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The thiopurine S-methyltransferase (TPMT) gene encodes for the TPMT enzyme that plays a crucial role in the metabolism of thiopurine drugs. Genetic polymorphisms in this gene can affect the activity of the TPMT enzyme and have been correlated with variability in response to treatment with thiopurines. Advances in the pharmacogenetics of TPMT allowed the development of dosing recommendations and treatment strategies to optimize and individualize prescribing thiopurine in an attempt to enhance treatment efficacy while minimizing toxicity. The influence of genetic polymorphisms in the TPMT gene on clinical outcome has been well-documented and replicated in many studies. In this review, we provide an overview of the evolution, results, conclusions and recommendations of selected studies that investigated the influence of TPMT pharmacogenetics on thiopurine treatment in acute lymphoblastic leukemia, inflammatory bowel disease and autoimmune disorders. We focus mainly on prospective studies that explored the impact of individualized TPMT-based dosing of thiopurines on clinical response. Together, these studies demonstrate the importance of preemptive TPMT genetic screening and subsequent dose adjustment in mitigating the toxicity associated with thiopurine treatment while maintaining treatment efficacy and favorable long-term outcomes. In addition, we briefly address the cost-effectiveness of this pharmacogenetics approach and its impact on clinical practice as well as the importance of recent breakthrough advances in sequencing and genotyping techniques in refining the TPMT genetic screening process.
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Affiliation(s)
| | - Maja Krajinovic
- Departments of Pediatrics and Pharmacology, CHU Sainte-Justine Research Center, University of Montreal, Montreal, QC, Canada
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24
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Pharmacogénétique des immunosuppresseurs : état des connaissances et des pratiques – recommandations du Réseau national de pharmacogénétique (RNPGx). Therapie 2017; 72:269-284. [DOI: 10.1016/j.therap.2016.09.011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2016] [Accepted: 09/02/2016] [Indexed: 12/18/2022]
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Wong DR, Coenen MJH, Vermeulen SH, Derijks LJJ, van Marrewijk CJ, Klungel OH, Scheffer H, Franke B, Guchelaar HJ, de Jong DJ, Engels LGJB, Verbeek ALM, Hooymans PM. Early Assessment of Thiopurine Metabolites Identifies Patients at Risk of Thiopurine-induced Leukopenia in Inflammatory Bowel Disease. J Crohns Colitis 2017; 11:175-184. [PMID: 27402913 DOI: 10.1093/ecco-jcc/jjw130] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/17/2016] [Revised: 06/10/2016] [Accepted: 06/21/2016] [Indexed: 01/28/2023]
Abstract
BACKGROUND AND AIMS Only a quarter of thiopurine-induced myelotoxicity in inflammatory bowel disease [IBD] patients is related to thiopurine S-methyltransferase deficiency. We determined the predictive value of 6-thioguanine nucleotide [6-TGN] and 6-methylmercaptopurine ribonucleotide [6-MMPR] concentrations 1 week after initiation [T1] for development of leukopenia during the first 8 weeks of thiopurine treatment. METHODS The study was performed in IBD patients starting thiopurine therapy as part of the Dutch randomized controlled TOPIC trial [ClinicalTrials.gov NCT00521950]. Blood samples for metabolite measurement were collected at T1. Leukopenia was defined by leukocyte counts of <3.0 × 109/L. For comparison, patients without leukopenia who completed the 8 weeks on the stable dose were selected from the first 272 patients of the TOPIC trial. RESULTS Thirty-two patients with, and 162 patients without leukopenia were analysed. T1 threshold 6-TGN concentrations of 213 pmol/8 × 108 erythrocytes and 3525 pmol/8 × 108 erythrocytes for 6-MMPR were defined: patients exceeding these values were at increased leukopenia risk (odds ratio [OR] 6.2 [95% CI: 2.8-13.8] and 5.9 [95% CI: 2.7-13.3], respectively). Leukopenia rates were higher in patients treated with mercaptopurine, compared with azathioprine (OR 7.3 [95% CI: 3.1-17.0]), and concurrent anti-TNF therapy (OR 5.1 [95% CI: 1.6-16.4]). Logistic regression analysis of thiopurine type, threshold concentrations, and concurrent anti-tumour necrosis factor [TNF] therapy revealed that elevations of both T1 6-TGN and 6-MMPR resulted in the highest risk for leukopenia, followed by exceeding only the T1 6-MMPR or 6-TGN threshold concentration (area under the curve 0.84 [95% CI: 0.76-0.92]). CONCLUSIONS In ~80% of patients, leukopenia could be explained by T1 6-TGN and/or 6-MMPR elevations. Validation of the predictive model is needed before implementing in clinical practice.
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Affiliation(s)
- Dennis R Wong
- Department of Clinical Pharmacy, Pharmacology and Toxicology, Zuyderland Medical Center, Sittard-Geleen, The Netherlands
| | - Marieke J H Coenen
- Department of Human Genetics, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Sita H Vermeulen
- Department of Human Genetics, Radboud University Medical Center, Nijmegen, The Netherlands.,Department for Health Evidence, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Luc J J Derijks
- Department of Clinical Pharmacy, Máxima Medical Centre, Veldhoven, The Netherlands
| | - Corine J van Marrewijk
- Department of Human Genetics, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Olaf H Klungel
- Division of Pharmacoepidemiology and Clinical Pharmacology, Utrecht Institute of Pharmaceutical Sciences, Utrecht University, The Netherlands
| | - Hans Scheffer
- Department of Human Genetics, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Barbara Franke
- Department of Human Genetics, Radboud University Medical Center, Nijmegen, The Netherlands.,Department of Psychiatry, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Henk-Jan Guchelaar
- Department of Clinical Pharmacy and Toxicology, Leiden University Medical Centre, Leiden, The Netherlands
| | - Dirk J de Jong
- Department of Gastroenterology, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Leopold G J B Engels
- Department of Gastroenterology, Zuyderland Medical Center, Sittard-Geleen, The Netherlands
| | - André L M Verbeek
- Department for Health Evidence, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Piet M Hooymans
- Department of Clinical Pharmacy, Pharmacology and Toxicology, Zuyderland Medical Center, Sittard-Geleen, The Netherlands
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Woillard JB, Chouchana L, Picard N, Loriot MA. Pharmacogenetics of immunosuppressants: State of the art and clinical implementation - recommendations from the French National Network of Pharmacogenetics (RNPGx). Therapie 2017; 72:285-299. [PMID: 28318610 DOI: 10.1016/j.therap.2016.09.016] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2016] [Accepted: 09/02/2016] [Indexed: 12/21/2022]
Abstract
Therapeutic drug monitoring is already widely used for immunosuppressive drugs due to their narrow therapeutic index. This article summarizes evidence reported in the literature regarding the pharmacogenetics of (i) immunosuppressive drugs used in transplantation and (ii) azathioprine used in chronic inflammatory bowel disease. The conditions of use of currently available major pharmacogenetic tests are detailed and recommendations are provided based on a scale established by the RNPGx scoring tests as "essential", "advisable" and "potentially useful". Other applications for which the level of evidence is still debated are also discussed.
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Affiliation(s)
- Jean-Baptiste Woillard
- Service de pharmacologie, toxicologie et pharmacovigilance, centre de biologie et de recherche en santé, CHU de Limoges, 87042 Limoges, France; Université de Limoges UMR_S850, 87000 Limoges, France.
| | - Laurent Chouchana
- Service de pharmacologie, hôpital Cochin, Assistance publique-Hôpitaux de Paris (AP-HP), 75014 Paris, France
| | - Nicolas Picard
- Service de pharmacologie, toxicologie et pharmacovigilance, centre de biologie et de recherche en santé, CHU de Limoges, 87042 Limoges, France; Université de Limoges UMR_S850, 87000 Limoges, France
| | - Marie-Anne Loriot
- Inserm UMR_S1147, centre universitaire des Saints-Pères, 75006 Paris, France; Université Paris Descartes, Sorbonne Paris Cité, 75006 Paris, France; Service de biochimie, hôpital européen Georges-Pompidou, Assistance publique-Hôpitaux de Paris (AP-HP), 75015 Paris, France
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27
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Ma ALT, Bale G, Aitkenhead H, Marks SD. Measuring Erythrocyte Thiopurine Methyltransferase Activity in Children-Is It Helpful? J Pediatr 2016; 179:216-218. [PMID: 27640357 DOI: 10.1016/j.jpeds.2016.08.073] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/01/2015] [Revised: 08/17/2016] [Accepted: 08/22/2016] [Indexed: 01/13/2023]
Abstract
OBJECTIVE To assess the profile of thiopurine transmethyltransferase (TPMT) enzyme activities in children and discuss the utility of measuring TPMT levels before commencing azathioprine therapy. STUDY DESIGN Retrospective study in a single pediatric center of all patients who had TPMT enzyme assay measured during a 3-year period before the start of azathioprine therapy. Patients' TPMT enzyme activities were classified as normal (26-50 pmol/h/mgHb), intermediate (10-25 pmol/h/mgHb), and deficient (<10 pmol/h/mgHb). Medical and electronic prescribing records were studied, with records of patients' demographic data, diagnoses, dosages, and adverse drug reactions monitored. RESULTS A total of 228 (45% female) patients ages 1-18 years (median 10 years) were tested for TPMT activity. They were all subsequently commenced on azathioprine. Erythrocyte TPMT activities were 14-76 (median 33.7) pmol/h/mgHb with 88% and 12% of patient having normal and intermediate activity respectively (none were deficient). The initial prescribed dosage of azathioprine was 0.7-3.5 (median 2.0) mg/kg/day. Only 2 patients developed mild neutropenia and required reduction of azathioprine dosage. CONCLUSION This large cohort study demonstrates that the majority of pediatric patients had normal TMPT activities. We would recommend close monitoring of full blood counts after instituting azathioprine therapy but would question the cost-effectiveness of pretreatment TPMT activity in pediatric practice.
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Affiliation(s)
- Alison L T Ma
- Department of Pediatric Nephrology, Great Ormond Street Hospital for Children NHS Foundation Trust, London, United Kingdom.
| | - Gregory Bale
- Department of Pharmacy, Great Ormond Street Hospital for Children NHS Foundation Trust, London, United Kingdom
| | - Helen Aitkenhead
- Department of Chemical Pathology, Great Ormond Street Hospital for Children National Health Service (NHS) Foundation Trust, London, United Kingdom
| | - Stephen D Marks
- Department of Pediatric Nephrology, Great Ormond Street Hospital for Children NHS Foundation Trust, London, United Kingdom
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Meijer B, Mulder CJJ, van Bodegraven AA, de Boer NKH. How I treat my inflammatory bowel disease-patients with thiopurines? World J Gastrointest Pharmacol Ther 2016; 7:524-530. [PMID: 27867685 PMCID: PMC5095571 DOI: 10.4292/wjgpt.v7.i4.524] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/21/2016] [Revised: 09/12/2016] [Accepted: 10/09/2016] [Indexed: 02/06/2023] Open
Abstract
Thiopurines are essential drugs to maintain remission in patients with inflammatory bowel disease (IBD). Thiopurines used in IBD are azathioprine (2.0-2.5 mg/kg), mercaptopurine (1.0-1.5 mg/kg) and thioguanine (0.2-0.3 mg/kg). However, mainly due to numerous adverse events associated with thiopurine use, almost 50% of the patients have to discontinue conventional thiopurine treatment. Extensive monitoring and the application of several treatment strategies, such as split-dose administration, co-administration with allopurinol or dose reduction/increase, may increase the chance of successful therapy. With this review, we provide practical information on how thiopurines are initiated and maintained in two thiopurine research centers in The Netherlands. We provide clinical information concerning safety issues, indications and management of therapy that may serve as a guide for the administration of thiopurines in IBD patients in daily practice.
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Mlakar V, Huezo-Diaz Curtis P, Satyanarayana Uppugunduri CR, Krajinovic M, Ansari M. Pharmacogenomics in Pediatric Oncology: Review of Gene-Drug Associations for Clinical Use. Int J Mol Sci 2016; 17:ijms17091502. [PMID: 27618021 PMCID: PMC5037779 DOI: 10.3390/ijms17091502] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2016] [Revised: 08/02/2016] [Accepted: 08/15/2016] [Indexed: 02/07/2023] Open
Abstract
During the 3rd congress of the European Society of Pharmacogenomics and Personalised Therapy (ESPT) in Budapest in 2015, a preliminary meeting was held aimed at establishing a pediatric individualized treatment in oncology and hematology committees. The main purpose was to facilitate the transfer and harmonization of pharmacogenetic testing from research into clinics, to bring together basic and translational research and to educate health professionals throughout Europe. The objective of this review was to provide the attendees of the meeting as well as the larger scientific community an insight into the compiled evidence regarding current pharmacogenomics knowledge in pediatric oncology. This preliminary evaluation will help steer the committee’s work and should give the reader an idea at which stage researchers and clinicians are, in terms of personalizing medicine for children with cancer. From the evidence presented here, future recommendations to achieve this goal will also be suggested.
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Affiliation(s)
- Vid Mlakar
- Cansearch Research Laboratory, Geneva University Medical School, Avenue de la Roseraie 64, 1205 Geneva, Switzerland.
| | - Patricia Huezo-Diaz Curtis
- Cansearch Research Laboratory, Geneva University Medical School, Avenue de la Roseraie 64, 1205 Geneva, Switzerland.
| | | | - Maja Krajinovic
- Charles-Bruneau Cancer Center, Centre hospitalier universitaire Sainte-Justine, 4515 Rue de Rouen, Montreal, QC H1V 1H1, Canada.
- Department of Pediatrics, University of Montreal, 2900 Boulevard Edouard-Montpetit, Montreal, QC H3T 1J4, Canada.
- Department of Pharmacology, Faculty of Medicine, University of Montreal, 2900 Boulevard Edouard-Montpetit, Montreal, QC H3T 1J4, Canada.
| | - Marc Ansari
- Cansearch Research Laboratory, Geneva University Medical School, Avenue de la Roseraie 64, 1205 Geneva, Switzerland.
- Pediatric Department, Onco-Hematology Unit, Geneva University Hospital, Rue Willy-Donzé 6, 1205 Geneva, Switzerland.
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Roy LM, Zur RM, Uleryk E, Carew C, Ito S, Ungar WJ. Thiopurine S-methyltransferase testing for averting drug toxicity in patients receiving thiopurines: a systematic review. Pharmacogenomics 2016; 17:633-56. [PMID: 27020704 PMCID: PMC4931919 DOI: 10.2217/pgs.16.12] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
AIM Thiopurine S-methyltransferase (TPMT) testing is used in patients receiving thiopurines to identify enzyme deficiencies and risk for adverse drug reactions. It is uncertain whether genotyping is superior to phenotyping. The objectives were to conduct a systematic review of TPMT-test performance studies. MATERIALS & METHODS Electronic and grey literature sources were searched for studies reporting test performance compared with a reference standard. Sixty-six eligible studies were appraised for quality. RESULTS Thirty phenotype-genotype and six phenotype-phenotype comparisons were of high quality. The calculated sensitivity and specificity for genotyping to identify a homozygous mutation ranged from 0.0-100.0% and from 97.8-100.0%, respectively. CONCLUSION Clinical decision-makers require high-quality evidence of clinical validity and clinical utility of TPMT genotyping to ensure appropriate use in patients.
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Affiliation(s)
- Lilla M Roy
- Child Health Evaluative Sciences, The Hospital for Sick Children Research Institute, Toronto, Canada
| | - Richard M Zur
- Child Health Evaluative Sciences, The Hospital for Sick Children Research Institute, Toronto, Canada
| | - Elizabeth Uleryk
- Library Services, The Hospital for Sick Children, Toronto, Canada
| | - Chris Carew
- Centre for Genetic Medicine, The Hospital for Sick Children, Toronto, Canada
| | - Shinya Ito
- Division of Clinical Pharmacology & Toxicology, The Hospital for Sick Children, Toronto, Canada
- Departments of Pharmacology & Pharmacy, Faculty of Medicine Department of Paediatrics, University of Toronto, Canada
| | - Wendy J Ungar
- Child Health Evaluative Sciences, The Hospital for Sick Children Research Institute, Toronto, Canada
- Institute for Health Policy, Management & Evaluation, University of Toronto, Canada
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Moon W, Loftus EV. Review article: recent advances in pharmacogenetics and pharmacokinetics for safe and effective thiopurine therapy in inflammatory bowel disease. Aliment Pharmacol Ther 2016; 43:863-883. [PMID: 26876431 DOI: 10.1111/apt.13559] [Citation(s) in RCA: 72] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/24/2015] [Revised: 08/26/2015] [Accepted: 01/26/2016] [Indexed: 12/16/2022]
Abstract
BACKGROUND Azathioprine and mercaptopurine have a pivotal role in the treatment of inflammatory bowel disease (IBD). However, because of their complex metabolism and potential toxicities, optimal use of biomarkers to predict adverse effects and therapeutic response is paramount. AIM To provide a comprehensive review focused on pharmacogenetics and pharmacokinetics for safe and effective thiopurine therapy in IBD. METHODS A literature search up to July 2015 was performed in PubMed using a combination of relevant MeSH terms. RESULTS Pre-treatment thiopurine S-methyltransferase typing plus measurement of 6-tioguanine nucleotides and 6-methylmercaptopurine ribonucleotides levels during treatment have emerged with key roles in facilitating safe and effective thiopurine therapy. Optimal use of these tools has been shown to reduce the risk of adverse effects by 3-7%, and to improve efficacy by 15-30%. For the introduction of aldehyde oxidase (AOX) into clinical practice, the association between AOX activity and AZA dose requirements should be positively confirmed. Inosine triphosphatase assessment associated with adverse effects also shows promise. Nucleoside diphosphate-linked moiety X-type motif 15 variants have been shown to predict myelotoxicity on thiopurines in East Asian patients. However, the impact of assessments of xanthine oxidase, glutathione S-transferase, hypoxanthine guanine phosphoribosyltransferase and inosine monophosphate dehydrogenase appears too low to favour incorporation into clinical practice. CONCLUSIONS Measurement of thiopurine-related enzymes and metabolites reduces the risk of adverse effects and improves efficacy, and should be considered part of standard management. However, this approach will not predict or avoid all adverse effects, and careful clinical and laboratory monitoring of patients receiving thiopurines remains essential.
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Affiliation(s)
- W Moon
- Division of Gastroenterology and Hepatology, Mayo Clinic, Rochester, MN, USA.,Department of Internal Medicine, Kosin University College of Medicine, Busan, Korea
| | - E V Loftus
- Division of Gastroenterology and Hepatology, Mayo Clinic, Rochester, MN, USA
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Kitley J, Palace J. Therapeutic options in neuromyelitis optica spectrum disorders. Expert Rev Neurother 2016; 16:319-29. [DOI: 10.1586/14737175.2016.1150178] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
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Association between Thiopurine S-Methyltransferase Polymorphisms and Azathioprine-Induced Adverse Drug Reactions in Patients with Autoimmune Diseases: A Meta-Analysis. PLoS One 2015; 10:e0144234. [PMID: 26633017 PMCID: PMC4669175 DOI: 10.1371/journal.pone.0144234] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2015] [Accepted: 11/16/2015] [Indexed: 01/27/2023] Open
Abstract
Purpose Azathioprine (AZA) is widely used as an immunosuppressive drug in autoimmune diseases, but its use is limited by significant adverse drug reactions (ADRs). Thiopurine S-methyltransferase (TPMT) is an important enzyme involved in AZA metabolism. Several clinical guidelines recommend determining TPMT genotype or phenotype before initiating AZA therapy. Although several studies have investigated the association between TPMT polymorphisms and AZA-induced ADRs, the results are inconsistent. The purpose of this study is to evaluate whether there is an association between TPMT polymorphisms and AZA-induced ADRs using meta-analysis. Methods We explored PubMed, Web of Science and Embase for articles on TPMT polymorphisms and AZA-induced ADRs. Studies that compared TPMT polymorphisms with-ADRs and without-ADRs in patients with autoimmune diseases were included. Relevant outcome data from all the included articles were extracted and the pooled odds ratios (ORs) with corresponding 95% confidence intervals (CIs) were calculated using Revman 5.3 software. Results Eleven published studies, with a total of 651 patients with autoimmune diseases, investigated associations between TPMT polymorphisms and AZA-induced ADRs, were included in this meta-analysis. Our meta-analysis demonstrated that TPMT polymorphisms were significantly associated with AZA-induced overall ADRs, bone marrow toxicity and gastric intolerance; pooled ORs were 3.12 (1.48–6.56), 3.76 (1.97–7.17) and 6.43 (2.04–20.25), respectively. TPMT polymorphisms were not associated with the development of hepatotoxicity; the corresponding pooled OR was 2.86 (95%CI: 0.32–25.86). However, the association in GI subset could be driven by one single study. After this study was excluded, the OR was 2.11 (95%CI: 0.36–12.42); namely, the association became negative. Conclusions Our meta-analysis demonstrated an association of TPMT polymorphisms with overall AZA-induced ADRs, bone marrow toxicity and gastric intolerance, but not with hepatotoxicity. The presence of the normal TPMT genotypes cannot preclude the development of ADRs during AZA treatment, TPMT genotyping prior to commencing AZA therapy cannot replace, may augment, the current practice of regular monitoring of the white blood cell. Because of small sample sizes, large and extensive exploration was required to validate our findings.
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Coenen MJH, de Jong DJ, van Marrewijk CJ, Derijks LJJ, Vermeulen SH, Wong DR, Klungel OH, Verbeek ALM, Hooymans PM, Peters WHM, te Morsche RHM, Newman WG, Scheffer H, Guchelaar HJ, Franke B, Pierik M, Mares W, Hameeteman W, Wahab P, Seinen H, Rijk M, Harkema I, de Bièvre M, Oostenbrug L, Bakker C, Aquarius M, van Deursen C, van Nunen A, Goedhard J, Hamacher M, Gisbertz I, Brenninkmeijer B, Tan A, Aparicio-Pagés M, Witteman E, van Tuyl S, Breumelhof R, Stronkhorst A, Gilissen L, Schoon E, Tjhie-Wensing J, Temmerman A, Nicolaï J, van Bergeijk J, Bac D, Witteman B, Mahmmod N, Uil J, Akol H, Ouwendijk R, van Munster I, Pennings M, De Schryver A, van Ditzhuijsen T, Scheffer R, Römkens T, Schipper D, Bus P, Straathof J, Verhulst M, Boekema P, Kamphuis J, van Wijk H, Salemans J, Vermeijden J, van der Werf S, Verburg R, Spoelstra P, de Vree J, van der Linde K, Jebbink H, Jansen M, Holwerda H, van Bentem N, Kolkman J, Russel M, van Olffen G, Kerbert-Dreteler M, Bargeman M, Götz J, Schröder R, Jansen J, Bos L, Engels L, Romberg-Camps M, Keulen E, van Esch A, Drenth J, van Kouwen M, Wanten G, Bisseling T, Römkens T, van Vugt M, van de Meeberg P, van den Hazel S, Stuifbergen W, Grubben M, de Wit U, Dodemont G, Eichhorn R, van den Brande J, Naber AH, van Soest E, Kingma P, Talstra N, Bruin K, Wolfhagen F, Hommes D, van der Veek P, Hardwick J, Stuyt R, Fidder H, Oldenburg B, Tan T. Identification of Patients With Variants in TPMT and Dose Reduction Reduces Hematologic Events During Thiopurine Treatment of Inflammatory Bowel Disease. Gastroenterology 2015; 149:907-17.e7. [PMID: 26072396 DOI: 10.1053/j.gastro.2015.06.002] [Citation(s) in RCA: 149] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/06/2015] [Revised: 04/13/2015] [Accepted: 06/03/2015] [Indexed: 01/11/2023]
Abstract
BACKGROUND & AIMS More than 20% of patients with inflammatory bowel disease (IBD) discontinue thiopurine therapy because of severe adverse drug reactions (ADRs); leukopenia is one of the most serious ADRs. Variants in the gene encoding thiopurine S-methyltransferase (TPMT) alter its enzymatic activity, resulting in higher levels of thiopurine metabolites, which can cause leukopenia. We performed a prospective study to determine whether genotype analysis of TPMT before thiopurine treatment, and dose selection based on the results, affects the outcomes of patients with IBD. METHODS In a study performed at 30 Dutch hospitals, patients were assigned randomly to groups that received standard treatment (control) or pretreatment screening (intervention) for 3 common variants of TPMT (TPMT*2, TPMT*3A, and TPMT*3C). Patients in the intervention group found to be heterozygous carriers of a variant received 50% of the standard dose of thiopurine (azathioprine or 6-mercaptopurine), and patients homozygous for a variant received 0%-10% of the standard dose. We compared, in an intention-to-treat analysis, outcomes of the intervention (n = 405) and control groups (n = 378) after 20 weeks of treatment. Primary outcomes were the occurrence of hematologic ADRs (leukocyte count < 3.0*10(9)/L or reduced platelet count < 100*10(9)/L) and disease activity (based on the Harvey-Bradshaw Index for Crohn's disease [n = 356] or the partial Mayo score for ulcerative colitis [n = 253]). RESULTS Similar proportions of patients in the intervention and control groups developed a hematologic ADR (7.4% vs 7.9%; relative risk, 0.93; 95% confidence interval, 0.57-1.52) in the 20 weeks of follow-up evaluation; the groups also had similar mean levels of disease activity (P = .18 for Crohn's disease and P = .14 for ulcerative colitis). However, a significantly smaller proportion of carriers of the TPMT variants in the intervention group (2.6%) developed hematologic ADRs compared with patients in the control group (22.9%) (relative risk, 0.11; 95% confidence interval, 0.01-0.85). CONCLUSIONS Screening for variants in TPMT did not reduce the proportions of patients with hematologic ADRs during thiopurine treatment for IBD. However, there was a 10-fold reduction in hematologic ADRs among variant carriers who were identified and received a dose reduction, compared with variant carriers who did not, without differences in treatment efficacy. ClinicalTrials.gov number: NCT00521950.
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Affiliation(s)
- Marieke J H Coenen
- Department of Human Genetics, Radboud Institute for Health Sciences, Radboud university medical center, Nijmegen, The Netherlands.
| | - Dirk J de Jong
- Department of Gastroenterology, Radboud Institute for Molecular Life Sciences, Radboud university medical center, Nijmegen, The Netherlands
| | - Corine J van Marrewijk
- Department of Human Genetics, Radboud Institute for Health Sciences, Radboud university medical center, Nijmegen, The Netherlands
| | - Luc J J Derijks
- Department of Clinical Pharmacy, Máxima Medical Centre, Veldhoven, The Netherlands
| | - Sita H Vermeulen
- Department of Human Genetics, Radboud Institute for Health Sciences, Radboud university medical center, Nijmegen, The Netherlands; Radboud Institute for Health Sciences, Radboud university medical center, Nijmegen, The Netherlands
| | - Dennis R Wong
- Department of Clinical Pharmacy and Toxicology, Orbis Medical Center, Sittard-Geleen, The Netherlands
| | - Olaf H Klungel
- Department of Pharmacoepidemiology and Pharmacotherapy, Utrecht Institute of Pharmaceutical Sciences, Utrecht University, Utrecht, The Netherlands
| | - Andre L M Verbeek
- Radboud Institute for Health Sciences, Radboud university medical center, Nijmegen, The Netherlands
| | - Piet M Hooymans
- Department of Clinical Pharmacy and Toxicology, Orbis Medical Center, Sittard-Geleen, The Netherlands
| | - Wilbert H M Peters
- Department of Gastroenterology, Radboud Institute for Molecular Life Sciences, Radboud university medical center, Nijmegen, The Netherlands
| | - Rene H M te Morsche
- Department of Gastroenterology, Radboud Institute for Molecular Life Sciences, Radboud university medical center, Nijmegen, The Netherlands
| | - William G Newman
- Centre for Genomic Medicine, St Mary's Hospital, Manchester Academic Health Science Centre, University of Manchester, Manchester, United Kingdom
| | - Hans Scheffer
- Department of Human Genetics, Donders Centre for Neuroscience, Radboud university medical center, Nijmegen, The Netherlands
| | - Henk-Jan Guchelaar
- Department of Clinical Pharmacy and Toxicology, Leiden University Medical Center, Leiden, The Netherlands
| | - Barbara Franke
- Department of Human Genetics, Donders Centre for Neuroscience, Radboud university medical center, Nijmegen, The Netherlands; Department of Psychiatry, Donders Centre for Neuroscience, Radboud university medical center, Nijmegen, The Netherlands
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Konidari A, Anagnostopoulos A, Bonnett LJ, Pirmohamed M, El-Matary W. Thiopurine monitoring in children with inflammatory bowel disease: a systematic review. Br J Clin Pharmacol 2015; 78:467-76. [PMID: 24592889 DOI: 10.1111/bcp.12365] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2013] [Accepted: 02/14/2014] [Indexed: 12/13/2022] Open
Abstract
AIMS The aim was to systematically review the evidence on the clinical usefulness of thiopurine metabolite and white blood count (WBC) monitoring in the assessment of clinical outcomes in children with inflammatory bowel disease (IBD). METHODS Medline, Embase, Cochrane Central Register of controlled trials and http://www.clinicaltrials.gov were screened in adherence to the PRISMA statement by two independent reviewers for identification of eligible studies. Eligible studies were randomized controlled trials (RCTs), cohort studies and large case series of children with inflammatory bowel disease (IBD) (<18 years) who underwent monitoring of thiopurine metabolites and/or WBC. RESULTS Fifteen papers were identified (n = 1026). None of the eligible studies were RCTs. High 6-thioguanine nucleotide (6TGN) concentrations were not consistently associated with leucopenia. Leucopenia was not associated with achievement of clinical remission. A positive but not consistent correlation between 6TGN and clinical remission was reported. Haematological toxicity could not be reliably assessed with 6TGN measurements only. A number of studies supported the use of high 6-methylmercaptopurine ribonucleotides (6MMPR) as an indicator of hepatotoxicity. Low thiopurine metabolite concentration may be indicative of non-compliance. CONCLUSION Thiopurine metabolite testing does not safely predict clinical outcome, but may facilitate toxicity surveillance and treatment optimization in poor responders. Current evidence favours the combination of thiopurine metabolite/WBC monitoring and clinic follow-up for prompt identification of haematologic/hepatic toxicity safe dose adjustment, and treatment modification in cases of suboptimal clinical outcome or non-compliance. Well designed RCTs for the identification of robust surrogate markers of thiopurine efficacy and toxicity are required.
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Affiliation(s)
- Anastasia Konidari
- Department of Clinical and Molecular Pharmacology, Wolfson Centre for Personalised Medicine, Institute for Translational Medicine, University of Liverpool, Liverpool, UK
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Goel RM, Blaker P, Mentzer A, Fong SCM, Marinaki AM, Sanderson JD. Optimizing the use of thiopurines in inflammatory bowel disease. Ther Adv Chronic Dis 2015; 6:138-46. [PMID: 25954498 PMCID: PMC4416969 DOI: 10.1177/2040622315579063] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Immunomodulator drugs, of which thiopurines can be considered the backbone, are widely used in the treatment of inflammatory bowel disease. They have been shown to be highly effective and safe; however, a significant proportion of patients are deemed to have a poor response or suffer adverse reactions. Knowing how to monitor and optimize thiopurine therapy in these scenarios is crucial to effective management. We discuss the metabolism of thiopurines, the use of enzyme/metabolite testing to guide treatment, as well as strategies to circumvent toxicity and side effects, such as allopurinol coprescription. The indications, use in pregnancy, safety profile and duration of thiopurine therapy are also discussed.
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Affiliation(s)
- Rishi M Goel
- Guy's & St Thomas' Hospitals - Gastroenterology, Westminster Bridge Road, London SE1 7EH, UK
| | - Paul Blaker
- Guy's & St Thomas' Hospitals - Gastroenterology, London, UK
| | - Alex Mentzer
- Guy's & St Thomas' Hospitals - Gastroenterology, London, UK
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Liu YP, Wu HY, Yang X, Xu HQ, Li YC, Shi DC, Huang JF, Huang Q, Fu WL. Association between thiopurine S-methyltransferase polymorphisms and thiopurine-induced adverse drug reactions in patients with inflammatory bowel disease: a meta-analysis. PLoS One 2015; 10:e0121745. [PMID: 25799415 PMCID: PMC4370632 DOI: 10.1371/journal.pone.0121745] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2014] [Accepted: 02/03/2015] [Indexed: 12/17/2022] Open
Abstract
Purpose Thiopurine drugs are well established treatments in the management of inflammatory bowel disease (IBD), but their use is limited by significant adverse drug reactions (ADRs). Thiopurine S-methyltransferase (TPMT) is an important enzyme involved in thiopurine metabolism. Several clinical guidelines recommend determining TPMT genotype or phenotype before initiating thiopurine therapy. Although several studies have investigated the association between TPMT polymorphisms and thiopurine-induced ADRs, the results are inconsistent. The purpose of this study is to evaluate whether there is an association between TPMT polymorphisms and thiopurine-induced ADRs using meta-analysis. Methods We explored PubMed, Web of Science and Embase for articles on TPMT polymorphisms and thiopurine-induced ADRs. Studies that compared TPMT polymorphisms with-ADRs and without-ADRs in IBD patients were included. Relevant outcome data from all the included articles were extracted and the pooled odds ratio (OR) with corresponding 95% confidence intervals were calculated using Revman 5.3 software. Results Fourteen published studies, with a total of 2,206 IBD patients, which investigated associations between TPMT polymorphisms and thiopurine-induced ADRs were included this meta-analysis. Our meta-analysis demonstrated that TPMT polymorphisms were significantly associated with thiopurine-induced overall ADRs and bone marrow toxicity; pooled ORs were 3.36 (95%CI: 1.82–6.19) and 6.67 (95%CI: 3.88–11.47), respectively. TPMT polymorphisms were not associated with the development of other ADRs including hepatotoxicity, pancreatitis, gastric intolerance, flu-like symptoms and skin reactions; the corresponding pooled ORs were 1.27 (95%CI: 0.60–2.71), 0.97 (95%CI: 0.38–2.48), 1.82 (95%CI: 0.93–3.53), 1.28 (95%CI: 0.47–3.46) and 2.32 (95%CI: 0.86–6.25), respectively. Conclusions Our meta-analysis demonstrated an association of TPMT polymorphisms with overall thiopurine-induced ADRs and bone marrow toxicity, but not with hepatotoxicity, pancreatitis, flu-like symptoms, gastric intolerance and skin reactions. These findings suggest that pretesting the TPMT genotype could be helpful in clinical practice before initiating thiopurine therapy. However, white blood cell count analysis should be the mainstay for follow-up.
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Affiliation(s)
- Yue-Ping Liu
- Department of Laboratory Medicine, Southwest Hospital, Third Military Medical University, Chongqing, 400038, China
| | - Hai-Yan Wu
- Department of Laboratory Medicine, Southwest Hospital, Third Military Medical University, Chongqing, 400038, China
| | - Xiang Yang
- Department of Laboratory Medicine, Southwest Hospital, Third Military Medical University, Chongqing, 400038, China
| | - Han-Qing Xu
- Department of Laboratory Medicine, Southwest Hospital, Third Military Medical University, Chongqing, 400038, China
| | - Yong-Chuan Li
- Department of Laboratory Medicine, Southwest Hospital, Third Military Medical University, Chongqing, 400038, China
| | - Da-Chuan Shi
- Department of Laboratory Medicine, Southwest Hospital, Third Military Medical University, Chongqing, 400038, China
| | - Jun-Fu Huang
- Department of Laboratory Medicine, Southwest Hospital, Third Military Medical University, Chongqing, 400038, China
| | - Qing Huang
- Department of Laboratory Medicine, Southwest Hospital, Third Military Medical University, Chongqing, 400038, China
| | - Wei-Ling Fu
- Department of Laboratory Medicine, Southwest Hospital, Third Military Medical University, Chongqing, 400038, China
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Hullah EA, Blaker PA, Marinaki AM, Escudier MP, Sanderson JD. A practical guide to the use of thiopurines in oral medicine. J Oral Pathol Med 2014; 44:761-8. [PMID: 25529219 DOI: 10.1111/jop.12274] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/08/2014] [Indexed: 12/11/2022]
Abstract
Thiopurines are widely used as first-line immunosuppressive therapies in the management of chronic inflammatory oral disease. However, despite over half a century of clinical experience, the evidence base for their use is limited. The aims of this paper were to review the evidence for the use of thiopurines in oral medicine and provide a contemporary model of thiopurine metabolism and mechanism of action and a rationale for clinical use and safe practice.
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Affiliation(s)
- E A Hullah
- Oral Medicine, King's College London Dental Institute, London, UK
| | - P A Blaker
- Gastroenterology, Guy's & St Thomas' Hospitals NHS Foundation Trust, Guy's Hospital, Great Maze Pond, London, UK
| | - A M Marinaki
- Purine Research Laboratory, Viapath, Guy's & St Thomas' Hospitals NHS Foundation Trust, Guy's Hospital, Great Maze Pond, London, UK
| | - M P Escudier
- Oral Medicine, King's College London Dental Institute, London, UK
| | - J D Sanderson
- Gastroenterology, Guy's & St Thomas' Hospitals NHS Foundation Trust, Guy's Hospital, Great Maze Pond, London, UK
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Lennard L. Implementation of TPMT testing. Br J Clin Pharmacol 2014; 77:704-14. [PMID: 23962279 DOI: 10.1111/bcp.12226] [Citation(s) in RCA: 89] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2013] [Accepted: 07/23/2013] [Indexed: 12/21/2022] Open
Abstract
The activity of the enzyme thiopurine methyltransferase (TPMT) is regulated by a common genetic polymorphism. One in 300 individuals lack enzyme activity and 11% are heterozygous for a variant low activity allele and have an intermediate activity. The thiopurine drugs azathioprine, mercaptopurine and thioguanine are substrates for TPMT; these drugs exhibit well documented myelosuppressive effects on haematopoietic cells and have a track record of idiosyncratic drug reactions. The development of severe bone marrow toxicity, in patients taking standard doses of thiopurine drugs, is associated with TPMT deficiency whilst the TPMT heterozygote is at an increased risk of developing myelosuppression. Factors influencing TPMT enzyme activity, as measured in the surrogate red blood cell, are discussed in this review to enable an appreciation of why concordance between TPMT genotype and phenotype is not 100%. This is particularly important for lower/intermediate TPMT activities to avoid misclassification of TPMT status. TPMT testing is now widely available in routine service laboratories. The British National Formulary suggests TPMT testing before starting thiopurine drugs. Dermatologists were quick to adopt routine TPMT testing whilst gastroenterologists do not specifically recommend TPMT screening. TPMT testing is mandatory prior to the use of mercaptopurine in childhood leukaemia. Thiopurine drug dose and other treatment related influences on cell counts explain some of the differing recommendations between clinical specialities. TPMT testing is cost-effective and the major role is in the identification of the TPMT deficient individual prior to the start of thiopurine drugs.
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Affiliation(s)
- Lynne Lennard
- Clinical Pharmacology Unit, Department of Human Metabolism, University of Sheffield, Sheffield, UK
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Mosli MH, Sandborn WJ, Kim RB, Khanna R, Al-Judaibi B, Feagan BG. Toward a personalized medicine approach to the management of inflammatory bowel disease. Am J Gastroenterol 2014; 109:994-1004. [PMID: 24842338 DOI: 10.1038/ajg.2014.110] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/09/2014] [Accepted: 03/30/2014] [Indexed: 12/11/2022]
Abstract
The medical management of inflammatory bowel disease (IBD) is evolving toward a personalized medicine-based model. Modern therapeutic algorithms that feature use of tumor necrosis factor (TNF) antagonists in combination with immunosuppressive are highly effective when initiated in high-risk patients early in the course of disease. Defined targets that guide intensification of therapy are critical interventions. In this model, therapy is optimized through appropriate pretreatment testing, therapeutic drug monitoring, and patient-based monitoring strategies. This review discusses the current application of personalized medicine to the management of IBD.
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Affiliation(s)
- Mahmoud H Mosli
- 1] Department of Medicine, Division of Gastroenterology, Western University, London, Ontario, Canada [2] Robarts Clinical Trials, Robarts Research Institute, London, Ontario, Canada [3] Department of Medicine, Division of Gastroenterology, King Abdulaziz University, Jeddah, Saudi Arabia
| | - William J Sandborn
- 1] Robarts Clinical Trials, Robarts Research Institute, London, Ontario, Canada [2] Division of Gastroenterology, University of California San Diego, La Jolla, California, USA
| | - Richard B Kim
- Department of Medicine, Division of Clinical Pharmacology, Western University, London, Ontario, Canada
| | - Reena Khanna
- 1] Department of Medicine, Division of Gastroenterology, Western University, London, Ontario, Canada [2] Robarts Clinical Trials, Robarts Research Institute, London, Ontario, Canada
| | - Bandar Al-Judaibi
- 1] Department of Medicine, Division of Gastroenterology, Western University, London, Ontario, Canada [2] Department of Medicine, Division of Gastroenterology, King Khalid University Hospital, King Saud University, Riyadh, Saudi Arabia
| | - Brian G Feagan
- 1] Department of Medicine, Division of Gastroenterology, Western University, London, Ontario, Canada [2] Robarts Clinical Trials, Robarts Research Institute, London, Ontario, Canada
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TPMT genetic variants are associated with increased rejection with azathioprine use in heart transplantation. Pharmacogenet Genomics 2014; 23:658-65. [PMID: 24121523 DOI: 10.1097/fpc.0000000000000005] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
OBJECTIVES Azathioprine (AZA) is an important immunosuppressant drug used in heart transplantation (HTX). Consensus guidelines recommend that patients with thiopurine S-methyltransferase (TPMT) genetic variants be started on lower AZA dose because of higher active metabolite levels and risk of adverse events. However, in-vitro lymphocyte proliferation assays performed in participants with inactive TPMT alleles have suggested that AZA use may result in decreased immunosuppressant efficacy as compared with wild-type (WT) individuals. The objective of this study was therefore to determine the effect of TPMT genetic variation on AZA efficacy or prevention of rejection in HTX recipients treated with AZA. PARTICIPANTS AND METHODS We genotyped 93 HTX recipients treated with AZA and measured erythrocyte TPMT enzyme activity. Acute rejection was monitored by routine endomyocardial biopsies. RESULTS There were 83 WT and 10 heterozygote (HZ) HTX recipients. TPMT activity level was lower in HZ compared with WT (13.1±2.8 vs. 21±4.5 U/ml red blood cell, P<0.001). Despite similar AZA dose, HZ developed severe rejection earlier (P<0.001), and the total rejection score was higher (P=0.02) than WT. AZA was discontinued more frequently in HZ (P=0.01) because of rejection. The incidence of leukopenia was similar between the groups (40 vs. 43%, P=1.0). CONCLUSION HTX recipients with TPMT genetic variant alleles who are treated with AZA develop acute rejection earlier, more frequently, and of greater severity. These patients, despite having lower TPMT enzymatic activity, should be monitored carefully for possible increased risk of acute rejection.
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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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Murray B, Hawes E, Lee RA, Watson R, Roederer MW. Genes and beans: pharmacogenomics of renal transplant. Pharmacogenomics 2014; 14:783-98. [PMID: 23651025 DOI: 10.2217/pgs.13.68] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Advances in the management of patients after solid organ transplantation have led to dramatic decreases in rates of acute rejection, but long-term graft and patient survival have remained unchanged. Individualized therapy after transplant will ideally provide adequate immunosuppression while limiting the adverse effects of drug therapy that significantly impact graft survival. Therapeutic drug monitoring represents the best approximation of individualized drug therapy in transplant at this time; however, obtaining pharmacogenomic data in transplant patients has the potential to enhance our current practice. Polymorphisms of target genes that impact pharmacokinetics have been identified for most immunosuppressants, including tacrolimus, cyclosporine, mycophenolate, azathioprine and sirolimus. In the future, pre-emptive assessment of a patient's genetic profile may inform drug selection and provide information on specific doses that will improve efficacy and limit toxicity.
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Affiliation(s)
- Brian Murray
- Critical Care Clinical Specialist, UNC Hospitals & Clinics, 101 Manning Drive, CB #7600, Chapel Hill, NC 27599-7600, USA.
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Abstract
Rheumatoid arthritis (RA) is a systemic inflammatory arthritis leading to severe joint damage and associated with high morbidity and mortality. Disease-modifying antirheumatic drugs (DMARDs) are the mainstay of treatment in RA. DMARDs not only relieve the clinical signs and symptoms of RA but also inhibit the radiographic progression of disease. In the last decade, a new class of disease-modifying medications, the biologic agents, has been added to the existing spectrum of DMARDs in RA. However, patients' response to these agents is not uniform with considerable variability in both efficacy and toxicity. There are no reliable means of predicting an individual patient's response to a given DMARD prior to initiation of therapy. In this chapter, the current published literature on the pharmacogenetics of traditional DMARDS and the newer biologic DMARDs in RA is highlighted. Pharmacogenetics may help individualize drug therapy in patients with RA in the near future.
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Affiliation(s)
- Deepali Sen
- Division of Rheumatology, Department of Medicine, Washington University School of Medicine, 660 S. Euclid Avenue, Campus Box 8045, St. Louis, MO, 63110, USA
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Trebst C, Jarius S, Berthele A, Paul F, Schippling S, Wildemann B, Borisow N, Kleiter I, Aktas O, Kümpfel T. Update on the diagnosis and treatment of neuromyelitis optica: recommendations of the Neuromyelitis Optica Study Group (NEMOS). J Neurol 2013; 261:1-16. [PMID: 24272588 PMCID: PMC3895189 DOI: 10.1007/s00415-013-7169-7] [Citation(s) in RCA: 397] [Impact Index Per Article: 36.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2013] [Revised: 10/15/2013] [Accepted: 10/16/2013] [Indexed: 12/26/2022]
Abstract
Neuromyelitis optica (NMO, Devic’s syndrome), long considered a clinical variant of multiple sclerosis, is now regarded as a distinct disease entity. Major progress has been made in the diagnosis and treatment of NMO since aquaporin-4 antibodies (AQP4-Ab; also termed NMO-IgG) were first described in 2004. In this review, the Neuromyelitis Optica Study Group (NEMOS) summarizes recently obtained knowledge on NMO and highlights new developments in its diagnosis and treatment, based on current guidelines, the published literature and expert discussion at regular NEMOS meetings. Testing of AQP4-Ab is essential and is the most important test in the diagnostic work-up of suspected NMO, and helps to distinguish NMO from other autoimmune diseases. Furthermore, AQP4-Ab testing has expanded our knowledge of the clinical presentation of NMO spectrum disorders (NMOSD). In addition, imaging techniques, particularly magnetic resonance imaging of the brain and spinal cord, are obligatory in the diagnostic workup. It is important to note that brain lesions in NMO and NMOSD are not uncommon, do not rule out the diagnosis, and show characteristic patterns. Other imaging modalities such as optical coherence tomography are proposed as useful tools in the assessment of retinal damage. Therapy of NMO should be initiated early. Azathioprine and rituximab are suggested as first-line treatments, the latter being increasingly regarded as an established therapy with long-term efficacy and an acceptable safety profile in NMO patients. Other immunosuppressive drugs, such as methotrexate, mycophenolate mofetil and mitoxantrone, are recommended as second-line treatments. Promising new therapies are emerging in the form of anti-IL6 receptor, anti-complement or anti-AQP4-Ab biologicals.
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Affiliation(s)
- Corinna Trebst
- Department of Neurology, Hannover Medical School, Hannover, Germany
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Affiliation(s)
- KL de Wit
- Department of Medicine, Guy's and St Thomas' NHS Foundation Trust, London
| | - BE White
- Department of Gastroenterology, Colchester Hospital University NHS Foundation Trust, Colchester CO4 5JL
| | - D Goldsmith
- Cardio-Renal Medicine in the Department of Nephrology, Guys and St Thomas’ NHS Foundation Trust, London
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Peterson JF, Bowton E, Field JR, Beller M, Mitchell J, Schildcrout J, Gregg W, Johnson K, Jirjis JN, Roden DM, Pulley JM, Denny JC. Electronic health record design and implementation for pharmacogenomics: a local perspective. Genet Med 2013; 15:833-41. [PMID: 24009000 PMCID: PMC3925979 DOI: 10.1038/gim.2013.109] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2013] [Accepted: 06/17/2013] [Indexed: 01/08/2023] Open
Abstract
PURPOSE The design of electronic health records to translate genomic medicine into clinical care is crucial to successful introduction of new genomic services, yet there are few published guides to implementation. METHODS The design, implemented features, and evolution of a locally developed electronic health record that supports a large pharmacogenomics program at a tertiary-care academic medical center was tracked over a 4-year development period. RESULTS Developers and program staff created electronic health record mechanisms for ordering a pharmacogenomics panel in advance of clinical need (preemptive genotyping) and in response to a specific drug indication. Genetic data from panel-based genotyping were sequestered from the electronic health record until drug-gene interactions met evidentiary standards and deemed clinically actionable. A service to translate genotype to predicted drug-response phenotype populated a summary of drug-gene interactions, triggered inpatient and outpatient clinical decision support, updated laboratory records, and created gene results within online personal health records. CONCLUSION The design of a locally developed electronic health record supporting pharmacogenomics has generalizable utility. The challenge of representing genomic data in a comprehensible and clinically actionable format is discussed along with reflection on the scalability of the model to larger sets of genomic data.
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Affiliation(s)
- Josh F Peterson
- 1] Department of Biomedical Informatics, Vanderbilt University Medical Center, Nashville, Tennessee, USA; [2] Division of General Internal Medicine, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee, USA
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Laha B, Guha R, Hazra A. Multiple cutaneous neutropenic ulcers associated with azathioprine. Indian J Pharmacol 2013; 44:646-8. [PMID: 23112431 PMCID: PMC3480802 DOI: 10.4103/0253-7613.100405] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/14/2012] [Revised: 04/29/2012] [Accepted: 07/01/2012] [Indexed: 11/09/2022] Open
Abstract
We report a case of neutropenic ulceration in a 42-year-old woman receiving azathioprine for pemphigus vulgaris. She developed multiple indolent ulcers involving the nose, neck, and back, after about 6–8 weeks following commencement of azathioprine 50 mg daily. The ulcers were large, disfiguring, dry, and with basal necrotic slough. They were painless and did not discharge pus. The absolute neutrophil count was severely depressed initially, but normalized following azathioprine withdrawal. Swab culture revealed colonization with Klebsiella pneumoniae and the ulcers healed with local debridement, treatment with imipenem, and topical application of mupirocin. However, nasal disfigurement persisted. Neutropenic ulceration is known to be associated with azathioprine therapy but we report this case because of the unusual presentation—indolent cutaneous ulcers. Early recognition of the problem and drug withdrawal can prevent complications like disfigurement.
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Affiliation(s)
- Baisakhi Laha
- Department of Anesthesiology and Critical Care, Command Hospital (Eastern Command), Alipore, India
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Ayesh BM, Harb WM, Abed AA. Thiopurine methyltransferase genotyping in Palestinian childhood acute lymphoblastic leukemia patients. BMC HEMATOLOGY 2013; 13:3. [PMID: 24499706 PMCID: PMC3816621 DOI: 10.1186/2052-1839-13-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 07/10/2012] [Accepted: 01/30/2013] [Indexed: 11/10/2022]
Abstract
BACKGROUND The genetic polymorphism of thiopurine methyltransferase (TPMT) is well characterized in most populations. Four common polymorphic alleles are associated with impaired activity of the enzyme. These are TPMT*2 (238G>C), TPMT*3B (c.460G>A), TPMT*3A (c.460G>A and c.719A>G) and TPMT*3C (c.719A>G). The aim of the present study was to determine the frequency of TPMT polymorphisms and their association with the occurrence of adverse events, during 6-mercaptopurine therapy in pediatric acute lymphoblastic leukemic (ALL) patients in Gaza Strip. METHODS A total of 56 DNA samples from all pediatric ALL patients admitted to the pediatric hematology departments of Gaza strip hospitals were analyzed. Genomic DNA from peripheral blood leukocytes was isolated and the TPMT*2, TPMT*3B TPMT*3A and TPMT*3C allelic polymorphism was determined by PCR-RFLP and allele specific PCR technique. RESULTS No TPMT*2, *3B or *3C alleles were detected. Only one, out of 56 patients, was found heterozygous for the TPMT*3A allele. Thus, the frequency of TPMT*3A allele was calculated to be 0.89%. Fourteen patients of ALL were suffering from myelotoxicity during 6-MP therapy. From our results, no significant association could be established between clinical and laboratory data and/or the presence of the mutation in TPMT gene. CONCLUSION TPMT*3A was the only deficiency allele detected in our population with an allelic frequency of 0.89%. Other polymorphic alleles in TPMT gene, or factors other than TPMT polymorphisms may be responsible for the development of myelosuppression in cases that don't carry the investigated TPMT alleles (*2, *3A, *3B and *3C). Therefore, more studies are recommended to study such factors.
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Affiliation(s)
| | | | - Abdalla Assaf Abed
- Biology Department, Islamic University of Gaza, Gaza, Palestinian authority
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Ibrahim I, Owen SA, Barton A. Genetics and the impact on treatment protocols in patients with rheumatoid arthritis. Expert Rev Clin Immunol 2013; 8:509-11. [PMID: 22992143 DOI: 10.1586/eci.12.51] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Ibrahim Ibrahim
- Arthritis Research UK Epidemiology Unit, Manchester Academy of Health Sciences, University of Manchester, Stopford Building, Oxford Road, Manchester, UK
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