1
|
Daraghmeh DN, Moghaddami M, Bobrovskaya L, Proudman SM, Wiese MD. Quantitation of methotrexate polyglutamates in human whole blood, erythrocytes and leukocytes collected via venepuncture and volumetric absorptive micro-sampling: a green LC-MS/MS-based method. Anal Bioanal Chem 2022; 414:6029-6046. [PMID: 35796782 PMCID: PMC9314280 DOI: 10.1007/s00216-022-04186-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Revised: 05/29/2022] [Accepted: 06/17/2022] [Indexed: 11/01/2022]
Abstract
Low-dose methotrexate (MTX) plays a key role in treatment of rheumatoid arthritis. However, not all patients respond satisfactorily, and no therapeutic drug monitoring has been implemented in clinical practice, despite the fact that MTX therapy has now been available for decades. Analysis of individual intracellular MTX metabolites among rheumatoid arthritis (RA) patients is hampered by the low intracellular concentrations of MTX-PGs which require a highly sensitive method to quantify. Here, we present a rapid and highly sensitive LC (HILIC) MS/MS method with LLOQ 0.1 nM, 0.8 nmol/L for each metabolite of MTX-PG1-5 and MTX-PG6-7 respectively. Over a linear range of 0.1-100 nM, 0.8-100 nmol/L for each metabolite of MTX-PG1-5 and MTX-PG6-7, respectively, the inter- and intra- accuracy and precision were within 15% of the nominal value for all MTX metabolites. The presented assay was used to assess and compare MTX metabolite concentrations extracted from four different matrices: red blood cells, plasma, peripheral blood mononuclear cells, and whole blood that have been collected either using traditional venepuncture or volumetric absorptive micro-sampling (VAMS) sampling techniques. The presented method not only improves analyte coverage and sensitivity as compared to other published methods; it also improves the greenness.
Collapse
Affiliation(s)
- Dala N Daraghmeh
- Centre for Pharmaceutical Innovation, UniSA: Clinical and Health Sciences, University of South Australia, GPO Box 2471, North Terrace, Adelaide, SA, 5000, Australia.
| | - Mahin Moghaddami
- Centre for Pharmaceutical Innovation, UniSA: Clinical and Health Sciences, University of South Australia, GPO Box 2471, North Terrace, Adelaide, SA, 5000, Australia
| | - Larisa Bobrovskaya
- Centre for Pharmaceutical Innovation, UniSA: Clinical and Health Sciences, University of South Australia, GPO Box 2471, North Terrace, Adelaide, SA, 5000, Australia
| | - Susanna M Proudman
- Royal Adelaide Hospital and The University of Adelaide, Adelaide Medical School, Adelaide, SA, Australia
| | - Michael D Wiese
- Centre for Pharmaceutical Innovation, UniSA: Clinical and Health Sciences, University of South Australia, GPO Box 2471, North Terrace, Adelaide, SA, 5000, Australia
| |
Collapse
|
2
|
Yin L, Ji Z, Cao H, Li Y, Huang J. Comparison of LC-MS 3 and LC-MRM strategy for quantification of methotrexate in human plasma and its application in therapeutic drug monitoring. J Pharm Biomed Anal 2021; 205:114345. [PMID: 34492453 DOI: 10.1016/j.jpba.2021.114345] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2021] [Revised: 07/24/2021] [Accepted: 08/25/2021] [Indexed: 11/19/2022]
Abstract
A simple, highly selective and high throughput liquid chromatography tandem mass spectrometry cubed (LC/MS3) method was developed and validated for quantification of methotrexate in human plasma. The MS3 detection is a scanning mode of QTrap MS systems or ion trap MS systems. After simple protein precipitation with methanol, methotrexate and methotrexate-d3 were separated on an Agilent Poroshell 120 SB-C18 column (4.6 × 50 mm, 2.7 µm) using isocratic elution with a mobile phase consisting of 60% 0.1% formic acid in water and 40% 0.1% formic acid in acetonitrile. The flow rate is 0.8 mL/min. MS3 detection in positive ion mode used the MRM3 transitions at m/z 455.2→308.2→175.1 for quantification of methotrexate and m/z 458.2→311.2→175.1 for quantification of methotrexate-d3. The total run time was only 3 min for each sample. The LC/MS3 assay was linear in the concentration range 10-3000 ng/mL(R2 ≥ 0.995) and the intra- and inter-day accuracies were< 3.72% and precisions were< 7.78% at all concentrations. The absolute recoveries (%) and matrix effect (%) for methotrexate in human plasma were between 92.6 and 114.3. The novelty of the presented methodology is the MS3 technique resulting in enhanced selectivity and sensitivity. The application of this LC-MS3 method was successfully completed on 46 human plasma samples and the quantitative results of identical human plasma samples were compared with another LC-MRM based method. Passing-Bablok regression coefficients demonstrated that there is no significant difference between the LC-MS3 method and LC-MRM method. Bland-Altman plots showed a concordant results, supporting the developed LC-MS3 method is a reliable and accurate assay for determination of methotrexate in human plasma. This work is also a proof of concept for using LC-MS3 technique to determination of chemicals in biological samples.
Collapse
Affiliation(s)
- Lei Yin
- Department of Laboratory Medicine, The First Hospital of Jilin University, Jilin University, Xinmin Street, Changchun 130061, PR China; School of Life and Pharmaceutical Sciences, Dalian University of Technology, Panjin 124221, PR China.
| | - Zhengchao Ji
- Department of Laboratory Medicine, The First Hospital of Jilin University, Jilin University, Xinmin Street, Changchun 130061, PR China
| | - Haiwei Cao
- Department of Laboratory Medicine, The First Hospital of Jilin University, Jilin University, Xinmin Street, Changchun 130061, PR China
| | - Yanyan Li
- Department of Laboratory Medicine, The First Hospital of Jilin University, Jilin University, Xinmin Street, Changchun 130061, PR China.
| | - Jing Huang
- Department of Laboratory Medicine, The First Hospital of Jilin University, Jilin University, Xinmin Street, Changchun 130061, PR China.
| |
Collapse
|
3
|
Rajšić I, Lazarević S, Đanić M, Al-Salami H, Mooranian A, Vukmirović S, Mikov M, Goločorbin-Kon S. Plasma Distribution of Methotrexate and Its Polyglutamates in Pediatric Acute Lymphoblastic Leukemia: Preliminary Insights. Eur J Drug Metab Pharmacokinet 2021; 47:127-134. [PMID: 34637107 DOI: 10.1007/s13318-021-00726-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/27/2021] [Indexed: 11/29/2022]
Abstract
BACKGROUND AND OBJECTIVE High-dose methotrexate (HD-MTX) is the mainstream therapy of current acute lymphoblastic leukemia (ALL) regimens, but frequent intra- and interindividual differences in the clinical response to HD-MTX lead to chemotherapeutic interruption or discontinuation. The exact mechanism of transport across the cell membrane and the disposition of active methotrexate metabolites-methotrexate polyglutamates (MTXPGs)-are not well described in the literature. The aim of this study was to gain more insight into the plasma distribution of methotrexate and MTXPGs in pediatric patients with ALL and to clarify the obscure pathways of MTXPGs. METHODS We prospectively measured the concentrations of MTXPG1-7 in plasma samples from three male pediatric patients treated with HD-MTX and leucovorin rescue according to the IC-BFM 2009 protocol using liquid chromatography-mass spectrometry (LC-MS). Blood samples were obtained at 24, 36, 42, and 48 h after the start of HD-MTX treatment. RESULTS Noticeable plasma concentrations of MTXPGs with a 2.2-fold interpatient variability were detected. The highest interindividual variability in total plasma MTXPG concentration was observed at 36 h, and ranged from 13.78 to 30.82 μmol/L. Among all patients, the predominant polyglutamate types in relation to the total plasma MTXPG concentration at each time point were MTXPG3 (16.71-30.02%) and MTXPG5 (26.23-38.60%), while MTXPG7 was the least abundant MTXPG (3.22-5.02%). CONCLUSION The presence of MTXPGs in plasma of patients with ALL could be related to the action of ABC efflux transporters on blood cells and hepatocytes resulting from the administration of high doses of methotrexate. This study may not draw definitive conclusions, but it does reduce uncertainty about the dynamics of methotrexate and its active metabolites, which may be of vital importance for achieving a clinical response.
Collapse
Affiliation(s)
- Ivana Rajšić
- Department of Pharmacology, Toxicology and Clinical Pharmacology, Faculty of Medicine, University of Novi Sad, Hajduk Veljkova 3, 21000, Novi Sad, Serbia
| | - Slavica Lazarević
- Department of Pharmacology, Toxicology and Clinical Pharmacology, Faculty of Medicine, University of Novi Sad, Hajduk Veljkova 3, 21000, Novi Sad, Serbia.
| | - Maja Đanić
- Department of Pharmacology, Toxicology and Clinical Pharmacology, Faculty of Medicine, University of Novi Sad, Hajduk Veljkova 3, 21000, Novi Sad, Serbia
| | - Hani Al-Salami
- Biotechnology and Drug Development Research Laboratory, Curtin Medical School, Curtin Health Innovation Research Institute, Curtin University, Perth, WA, Australia.,Ear Science Institute Australia, Queen Elizabeth II Medical Centre, Hearing Therapeutics, Nedlands, Perth, WA, 6102, Australia
| | - Armin Mooranian
- Biotechnology and Drug Development Research Laboratory, Curtin Medical School, Curtin Health Innovation Research Institute, Curtin University, Perth, WA, Australia.,Ear Science Institute Australia, Queen Elizabeth II Medical Centre, Hearing Therapeutics, Nedlands, Perth, WA, 6102, Australia
| | - Saša Vukmirović
- Department of Pharmacology, Toxicology and Clinical Pharmacology, Faculty of Medicine, University of Novi Sad, Hajduk Veljkova 3, 21000, Novi Sad, Serbia
| | - Momir Mikov
- Department of Pharmacology, Toxicology and Clinical Pharmacology, Faculty of Medicine, University of Novi Sad, Hajduk Veljkova 3, 21000, Novi Sad, Serbia
| | - Svetlana Goločorbin-Kon
- Department of Pharmacy, Faculty of Medicine, University of Novi Sad, Hajduk Veljkova 3, 21000, Novi Sad, Serbia
| |
Collapse
|
4
|
Zhang Y, Sun L, Zhao L, Wang X, Zhao Z, Mei S. Methotrexate Polyglutamates Analysis by Chromatography Methods in Biological Matrices: A Review. ANAL SCI 2021; 37:1655-1664. [PMID: 34024867 DOI: 10.2116/analsci.21r001] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Methotrexate (MTX) is used as an immunosuppressant and antineoplastic drug in clinical practice. MTX is a parent drug and converts to MTX polyglutamates (MTXPGs) to exhibit its biological activity. Clinical studies found that MTXPG levels were associated with MTX response and toxicities, especially at low doses. Due to huge variance of MTX response and toxicities between individuals, therapeutic drug monitoring is necessary for its use in individualized therapy. Various chromatography methods coupled with ultraviolet-visible detector, fluorescence detector and mass spectrometry have been reported for MTXPG analysis in various biological matrices. The aim of this paper is to review the chromatographic based methods for the measurement of total and/or individual MTXPGs. We searched Embase, Science Direct and PubMed databases using "methotrexate polyglutamate" and "chromatography" as search terms, and found 745 articles. Of those, 14 articles were extracted for this study. The key steps for method development (sample pretreatment, parameter optimization of liquid chromatography and mass spectrometry, selection of internal standard) and validation (lower limit of quantitation, accuracy, precision, recovery, matrix effect and stability) were analyzed and summarized, which might be helpful for researchers to develop their own methods.
Collapse
Affiliation(s)
- Yiming Zhang
- Department of Pharmacy, Beijing Tiantan Hospital, Capital Medical University.,Department of Clinical Pharmacology, College of Pharmaceutical Sciences, Capital Medical University
| | - Liyu Sun
- Department of Pharmacy, Beijing Tiantan Hospital, Capital Medical University.,Department of Clinical Pharmacology, College of Pharmaceutical Sciences, Capital Medical University
| | - Libo Zhao
- Department of Clinical Pharmacology, College of Pharmaceutical Sciences, Capital Medical University.,Department of Pharmacy, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health
| | - Xiaoling Wang
- Department of Clinical Pharmacology, College of Pharmaceutical Sciences, Capital Medical University.,Department of Pharmacy, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health
| | - Zhigang Zhao
- Department of Pharmacy, Beijing Tiantan Hospital, Capital Medical University.,Department of Clinical Pharmacology, College of Pharmaceutical Sciences, Capital Medical University
| | - Shenghui Mei
- Department of Pharmacy, Beijing Tiantan Hospital, Capital Medical University.,Department of Clinical Pharmacology, College of Pharmaceutical Sciences, Capital Medical University
| |
Collapse
|
5
|
Choi R, Chun MR, Park J, Won H, Kim S, Lee JW, Ju HY, Cho HW, Hyun JK, Koo HH, Yi ES, Lee SY. Methotrexate polyglutamate quantification for clinical application in patients with pediatric acute lymphoblastic leukemia in association with genetic polymorphisms. J Pharm Biomed Anal 2021; 201:114124. [PMID: 34000579 DOI: 10.1016/j.jpba.2021.114124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2021] [Revised: 04/22/2021] [Accepted: 05/03/2021] [Indexed: 11/16/2022]
Abstract
We developed and validated a quantification method for methotrexate (MTX) polyglutamates (MTX-PGs, MTX-PG1 to MTX-PG5) by liquid chromatography-tandem mass spectrometry using stable isotope-labeled internal standards and applied to 196 clinical samples collected from pediatric acute lymphoblastic leukemia patients treated with MTX. MTX-PGs levels and their proportions (%) in sum of all MTX-PGs (MTXSum) were evaluated in relation to TPMT, NUDT15, and MTHFR genotypes. For the developed method, linearity ranges 1-500 nmol/L, bias for accuracy 0.3-13.5 %, coefficient of variation for within- and between-run imprecision of 3.2-9.5% and 1.5-12.0%, respectively. Recoveries achieved were 74.2-105.8 %. There was no significant carryover. The median level of the MTXSum for 196 clinical samples was 129.4 nmol/L (interquartile range 28.1-241.2). MTX dose and MTX-PGs were associated (P < 0.05) and among five MTX-PGs, MTX-PG3 was the predominant form (median 41.7 %). The MTX-PG3 level was significantly higher in patients with TPMT *1/*3C than in patients with wild type and MTX-PG3% was significantly higher and MTX-PG5% was significantly lower in NUDT15 intermediate metabolizers than normal or indeterminate phenotypes (P < 0.05). This validated MTX-PGs quantification method can facilitate a better understanding of MTX metabolism and therapeutic drug monitoring for MTX treatment.
Collapse
Affiliation(s)
- Rihwa Choi
- Department of Laboratory Medicine and Genetics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea; Department of Laboratory Medicine, Green Cross Laboratories, Yongin, Gyeonggi, Republic of Korea
| | - Mi Ryung Chun
- Department of Laboratory Medicine and Genetics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Jisook Park
- Samsung Biomedical Research Institute, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Hojeong Won
- Statistics and Data Center, Research Institute for Future Medicine, Samsung Medical Center, Seoul, Republic of Korea
| | - Seonwoo Kim
- Statistics and Data Center, Research Institute for Future Medicine, Samsung Medical Center, Seoul, Republic of Korea
| | - Ji Won Lee
- Department of Pediatrics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea.
| | - Hee Young Ju
- Department of Pediatrics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Hee Won Cho
- Department of Pediatrics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Ju Kyung Hyun
- Department of Pediatrics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Hong Hoe Koo
- Department of Pediatrics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Eun Sang Yi
- Department of Pediatrics, Korea University Guro Hospital, Korea University College of Medicine, Seoul, Republic of Korea
| | - Soo-Youn Lee
- Department of Laboratory Medicine and Genetics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea; Department of Clinical Pharmacology and Therapeutics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea; Department of Health Science and Technology, Samsung Advanced Institute of Health Science and Technology, Sungkyunkwan University, Seoul, Republic of Korea.
| |
Collapse
|
6
|
Kim DH, Yoo YS, Yoo HJ, Choi YJ, Kim SA, Sheen DH, Lee SK, Lim MK, Cho K. Analysis of hair and plasma samples for methotrexate (MTX) and metabolite using high-performance liquid chromatography triple quadrupole mass spectrometry (LC-MS/MS) detection. JOURNAL OF MASS SPECTROMETRY : JMS 2021; 56:e4648. [PMID: 32954603 DOI: 10.1002/jms.4648] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Revised: 08/12/2020] [Accepted: 08/17/2020] [Indexed: 06/11/2023]
Abstract
Methotrexate (MTX), a folate antagonist, is the anchor drug used to treat several diseases. Therapeutic effects are attributed to intracellular levels of various methotrexate conjugates that are present in the cell as polyglutamates (MTX-Glu). The present study was conducted to develop a new liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS)-based assay to separately quantitate the MTX-Glu in hair cells, red blood cells, and serum using internal standards. Sample preparation consisted of extraction with an organic solution followed by solid-phase extraction. The presented methodology was applied for the analysis of methotrexate and its polyglutamates in hair cells, red blood cells, and serum obtained from clinical patients. The developed LC-ESI-MS/MS method for the quantitative measurement of MTX-Glu was both sensitive and precise within the clinically relevant range. This method is possibly be superior with respect to sensitivity, selectivity, and speed than all previously described approaches and can be easily applied in routine clinical tests owing to the combination of a simple pretreatment process with robust LC-MS/MS.
Collapse
Affiliation(s)
- Duck Hyun Kim
- Center of Research Equipment, Korea Basic Science Institute, 162, Yeonggudanji-ro, Ochang-eup, Cheongwon-gu, Cheongju-si, 28119, Republic of Korea
| | - Yeong Suk Yoo
- Product Analysis Team, Boryung Phamaceutical, 107, Neungan-ro, Danwon-gu, Ansan-si, Gyeonggi-do, Republic of Korea
| | - Hee Jin Yoo
- Center of Research Equipment, Korea Basic Science Institute, 162, Yeonggudanji-ro, Ochang-eup, Cheongwon-gu, Cheongju-si, 28119, Republic of Korea
| | - Yoon Ji Choi
- Center of Research Equipment, Korea Basic Science Institute, 162, Yeonggudanji-ro, Ochang-eup, Cheongwon-gu, Cheongju-si, 28119, Republic of Korea
| | - Soon Ae Kim
- Department of Pharmacology, Eulji University School of Medicine, Daejeon, Republic of Korea
| | - Dong-Hyuk Sheen
- Department of Medicine Division of Rheumatology, Eulji University School of Medicine, Daejeon, Republic of Korea
| | - Sang Kwang Lee
- Eulji Medi-Bio Research Insititute, Eulji University, Daejeon, Republic of Korea
| | - Mi Kyoung Lim
- Department of Medicine Division of Rheumatology, Eulji University School of Medicine, Daejeon, Republic of Korea
| | - Kun Cho
- Center of Research Equipment, Korea Basic Science Institute, 162, Yeonggudanji-ro, Ochang-eup, Cheongwon-gu, Cheongju-si, 28119, Republic of Korea
| |
Collapse
|
7
|
Wu J, Zhang S, Li J, Zhong X, Feng G, Hu L, He F, Cen H, Chen Y, He Y, Zeng H, Chen X, Mo X. Simultaneous determination of erythrocyte methotrexate polyglutamates by a novel and simple HPLC-MS/MS method with stable isotope-labeled internal standards. J Sep Sci 2021; 44:1852-1865. [PMID: 33646615 DOI: 10.1002/jssc.202001081] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2020] [Revised: 02/21/2021] [Accepted: 02/23/2021] [Indexed: 11/09/2022]
Abstract
Low-dose methotrexate is the first-line therapy for juvenile idiopathic arthritis. In vivo, methotrexate is converted into a series of methotrexate polyglutamates whose intracellular levels contribute significantly to its efficacy and toxicity. In this study, a novel high-performance liquid chromatography-tandem mass spectrometry method was developed and validated to simultaneously determine erythrocyte methotrexate polyglutamates using stable isotope-labeled internal standards. Erythrocyte samples were precipitated by perchloric acid and then determined on an XBridge BEH C18 column with an XP vanguard precolumn in 12 min. The mobile phase consisted of 10 nM ammonium acetate (pH 10) and methanol under gradient elution. The detection was carried out in multiple reaction monitoring mode via an electrospray ionization source in positive ionization mode. The calibration curve for each metabolite was linear from 2.0 to 500.0 nmol/L (r2 > 0.99). The intraday and interday accuracies were between 93.0 and 107.0%, and the corresponding precisions were between 0.8 and 5.2%. The relative recovery ranged from 82.7 to 105.1%, and the relative matrix effect varied from 96.5 to 104.4%. The erythrocyte metabolites were stable for 30 days at -80°C. This simple and accurate method is applicable to routine monitoring of the concentration of erythrocyte methotrexate polyglutamates in patients to achieve individualized treatment.
Collapse
Affiliation(s)
- Jingjing Wu
- Department of Pharmacy, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, P. R. China
| | - Song Zhang
- Pediatric Allergy Immunology & Rheumatology Department, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, P. R. China
| | - Jiali Li
- Institute of Clinical Pharmacology, School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou, P. R. China
| | - Xiaoli Zhong
- Institute of Clinical Pharmacology, School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou, P. R. China
| | - Guiping Feng
- Pediatric Allergy Immunology & Rheumatology Department, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, P. R. China
| | - Liangqing Hu
- Pediatric Allergy Immunology & Rheumatology Department, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, P. R. China
| | - Fan He
- Department of Pharmacy, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, P. R. China
| | - Hanjing Cen
- Department of Pharmacy, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, P. R. China
| | - Yilu Chen
- Department of Pharmacy, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, P. R. China
| | - Yanling He
- Department of Pharmacy, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, P. R. China
| | - Huasong Zeng
- Pediatric Allergy Immunology & Rheumatology Department, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, P. R. China
| | - Xiao Chen
- Department of Pharmacy, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, P. R. China
| | - Xiaolan Mo
- Department of Pharmacy, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, P. R. China.,Guangdong Provincial Key Laboratory of New Drug Design and Evaluation, Sun Yat-sen University, Guangzhou, P. R. China
| |
Collapse
|
8
|
Kodidela S, Dorababu P, Thakkar DN, Dubashi B, Sundaram R, Muralidharan N, Nidanapu RP, Aribandi A, Pradhan SC, Uppugunduri CRS. Association of NUDT15*3 and FPGS 2572C>T Variants with the Risk of Early Hematologic Toxicity During 6-MP and Low-Dose Methotrexate-Based Maintenance Therapy in Indian Patients with Acute Lymphoblastic Leukemia. Genes (Basel) 2020; 11:genes11060594. [PMID: 32481505 PMCID: PMC7349017 DOI: 10.3390/genes11060594] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2020] [Revised: 05/13/2020] [Accepted: 05/25/2020] [Indexed: 02/07/2023] Open
Abstract
Genetic variants influencing the pharmacokinetics and/or pharmacodynamics of the chemotherapeutic drugs used in Acute Lymphoblastic Leukemia (ALL) therapy often contribute to the occurrence of treatment related toxicity (TRT). In this study, we explored the association of candidate genetic variants with early hematological TRT (grade 3–4) occurring within the first 100 days of low-dose methotrexate and 6-mercaptopurine based maintenance therapy (n = 73). Fourteen variants in the following candidate genes were genotyped using allele discrimination assay by real-time PCR: ABCB1, DHFR, GGH, FPGS, MTHFR, RFC1, SLCO1B1, TPMT, and NUDT15. Methotrexate polyglutamate (MTXPG3-5) levels in red blood cells were measured by LC-MS/MS. Early hematological TRT (grade 3–4) was seen in 54.9% of patients. The NUDT15c.415T allele was associated with early TRT occurrence [HR: 3.04 (95% CI: 1.5–6.1); p = 0.007]. Sensitivity of early TRT prediction improved (from 30.7% to 89.7%) by considering FPGS variant (rs1544105’T’) carrier status along with NUDT15c.415T allele [HR = 2.7 (1.5–4.7, p = 0.008)]. None of the considered genetic variants were associated with MTXPG3-5 levels, which in turn were not associated with early TRT. NUDT15c.415T allele carrier status could be used as a stratifying marker for Indian ALL patients to distinguish patients at high or low risk of developing early hematological TRT.
Collapse
Affiliation(s)
- Sunitha Kodidela
- College of Pharmacy, University of Tennessee Heath Science Center, Memphis, TN 38163, USA
- Correspondence: (S.K.); (C.R.S.U.)
| | - Patchava Dorababu
- Department of Pharmacology, Apollo Institute of Medical Sciences and Research, Hyderabad 500090, India;
| | - Dimpal N. Thakkar
- Department of Pharmacology, Jawaharlal Institute of Postgraduate Medical Education & Research, Pondicherry 605006, India; (D.N.T.); (R.S.); (R.P.N.)
| | - Biswajit Dubashi
- Department of Medical Oncology, Jawaharlal Institute of Postgraduate Medical Education & Research, Pondicherry 605006, India;
| | - Rajan Sundaram
- Department of Pharmacology, Jawaharlal Institute of Postgraduate Medical Education & Research, Pondicherry 605006, India; (D.N.T.); (R.S.); (R.P.N.)
| | - Niveditha Muralidharan
- Department of Clinical Immunology, Jawaharlal Institute of Postgraduate Medical Education & Research, Pondicherry 605006, India;
| | - Ravi Prasad Nidanapu
- Department of Pharmacology, Jawaharlal Institute of Postgraduate Medical Education & Research, Pondicherry 605006, India; (D.N.T.); (R.S.); (R.P.N.)
| | - Anil Aribandi
- Division of Haemato-Oncology, Care Hospitals, Hyderabad 500019, India;
- American Oncology Institute, Nallagandla Serilingampalli, Hyderabad 500019, India
| | - Suresh Chandra Pradhan
- Department of Pharmacology, Kalinga Institute of Medical Sciences, Bhubaneswar 751024, India;
| | - Chakradhara Rao Satyanarayana Uppugunduri
- Onco-Hematology Unit, Research Platform of Pediatric Onco-Hematology, Department of Paediatrics, Gynaecology and Obstetrics, University Hospitals of Geneva, University of Geneva, 1205 Geneva, Switzerland
- Correspondence: (S.K.); (C.R.S.U.)
| |
Collapse
|
9
|
Karami F, Ranjbar S, Ghasemi Y, Negahdaripour M. Analytical methodologies for determination of methotrexate and its metabolites in pharmaceutical, biological and environmental samples. J Pharm Anal 2019; 9:373-391. [PMID: 31890337 PMCID: PMC6931080 DOI: 10.1016/j.jpha.2019.06.001] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2019] [Revised: 05/05/2019] [Accepted: 06/19/2019] [Indexed: 02/08/2023] Open
Abstract
Methotrexate (MTX) is a folate antagonist drug used for several diseases, such as cancers, various malignancies, rheumatoid arthritis (RA) and inflammatory bowel disease. Due to its structural features, including the presence of two carboxylic acid groups and its low native fluorescence, there are some challenges to develop analytical methods for its determination. MTX is metabolized to 7-hydroxymethotrexate (7-OH-MTX), 2,4-diamino-N10-methylpteroic acid (DAMPA), and the active MTX polyglutamates (MTXPGs) in the liver, intestine, and red blood cells (RBCs), respectively. Additionally, the drug has a narrow therapeutic range; hence, its therapeutic drug monitoring (TDM) is necessary to regulate the pharmacokinetics of the drug and to decrease the risk of toxicity. Due to environmental toxicity of MTX; its sensitive, fast and low cost determination in workplace environments is of great interest. A large number of methodologies including high performance liquid chromatography equipped with UV-visible, fluorescence, or electrochemical detection, liquid chromatography-mass spectroscopy, capillary electrophoresis, UV-visible spectrophotometry, and electrochemical methods have been developed for the quantitation of MTX and its metabolites in pharmaceutical, biological, and environmental samples. This paper will attempt to review several published methodologies and the instrumental conditions, which have been applied to measure MTX and its metabolites within the last decade.
Collapse
Affiliation(s)
- Forough Karami
- Pharmaceutical Sciences Research Center, Shiraz University of Medical Sciences, Shiraz, Iran
- Central Research Laboratory, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran
- Chemistry Department, Yasouj University, Yasouj, Iran
| | - Sara Ranjbar
- Pharmaceutical Sciences Research Center, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Younes Ghasemi
- Pharmaceutical Sciences Research Center, Shiraz University of Medical Sciences, Shiraz, Iran
- Department of Pharmaceutical Biotechnology, School of Pharmacy, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Manica Negahdaripour
- Pharmaceutical Sciences Research Center, Shiraz University of Medical Sciences, Shiraz, Iran
| |
Collapse
|
10
|
Mendoza-Santiago A, Becerra E, Garay E, Bah M, Berumen-Segura L, Escobar-Cabrera J, Hernández-Pérez A, García-Alcocer G. Glutamic Acid Increased Methotrexate Polyglutamation and Cytotoxicity in a CCRF-SB Acute Lymphoblastic Leukemia Cell Line. ACTA ACUST UNITED AC 2019; 55:medicina55120758. [PMID: 31779260 PMCID: PMC6956105 DOI: 10.3390/medicina55120758] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Revised: 11/04/2019] [Accepted: 11/20/2019] [Indexed: 11/23/2022]
Abstract
Background and Objectives: Acute lymphoblastic leukemia (ALL) is the most common type of cancer in childhood. The majority of patients respond to treatment, but those with resistant phenotypes suffer relapse or death. The antifolate methotrexate (MTX) is the most commonly used drug against ALL due to its efficacy. Once inside leukemic cells, MTX is metabolized into methotrexate polyglutamates (MTX-PG) by action of the enzyme folylpolyglutamate synthetase (FPGS), leading to a longer action compared to that of MTX alone. Materials and Methods: In this work, we demonstrated that the combination treatment of methotrexate and 5 and 10 mM glutamic acid could enhance methotrexate cytotoxicity in CCRF-SB (B-ALL) cells. In addition, MTX plus 20 mM glutamic acid was able to improve the synthesis of MTX-PG5. Results: All treatments induced an increase in FPGS expression compared to that of the control group. Furthermore, we detected different cellular expression patterns of FPGS in the different treatments. Conclusion: Based on these findings, we demonstrated that levels of methotrexate polyglutamates (MTX-PGs) could be a key determinant of methotrexate-induced cytotoxicity in CCRF-SB acute lymphoblastic leukemia cells.
Collapse
Affiliation(s)
- Alma Mendoza-Santiago
- Unidad de Investigación Genética, Facultad de Química, Universidad Autónoma de Querétaro, Centro Universitario, 76010 Querétaro, Mexico; (A.M.-S.); (E.B.); (L.B.-S.); (J.E.-C.)
| | - Edgardo Becerra
- Unidad de Investigación Genética, Facultad de Química, Universidad Autónoma de Querétaro, Centro Universitario, 76010 Querétaro, Mexico; (A.M.-S.); (E.B.); (L.B.-S.); (J.E.-C.)
| | - Edith Garay
- Laboratorio de Investigación en Productos Naturales, Facultad de Química, Universidad Autónoma de Querétaro, 76010 Querétaro, Mexico; (E.G.); (A.H.-P.)
| | - Moustapha Bah
- Instituto de Neurobiología, Universidad Nacional Autónoma de México, 04510 Mexico City, Mexico;
| | - Laura Berumen-Segura
- Unidad de Investigación Genética, Facultad de Química, Universidad Autónoma de Querétaro, Centro Universitario, 76010 Querétaro, Mexico; (A.M.-S.); (E.B.); (L.B.-S.); (J.E.-C.)
| | - Jesica Escobar-Cabrera
- Unidad de Investigación Genética, Facultad de Química, Universidad Autónoma de Querétaro, Centro Universitario, 76010 Querétaro, Mexico; (A.M.-S.); (E.B.); (L.B.-S.); (J.E.-C.)
| | - Abigail Hernández-Pérez
- Laboratorio de Investigación en Productos Naturales, Facultad de Química, Universidad Autónoma de Querétaro, 76010 Querétaro, Mexico; (E.G.); (A.H.-P.)
| | - Guadalupe García-Alcocer
- Unidad de Investigación Genética, Facultad de Química, Universidad Autónoma de Querétaro, Centro Universitario, 76010 Querétaro, Mexico; (A.M.-S.); (E.B.); (L.B.-S.); (J.E.-C.)
- Correspondence: ; Tel.: +524-421921200-5571; Fax: +524-421921302
| |
Collapse
|
11
|
Folyl polyglutamate synthethase (FPGS) gene polymorphisms may influence methotrexate adverse events in South Indian Tamil Rheumatoid Arthritis patients. THE PHARMACOGENOMICS JOURNAL 2019; 20:342-349. [DOI: 10.1038/s41397-019-0097-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2018] [Revised: 09/16/2019] [Accepted: 10/01/2019] [Indexed: 11/08/2022]
|
12
|
Nersting J, Nielsen SN, Grell K, Paerregaard M, Abrahamsson J, Lund B, Jonsson OG, Pruunsild K, Vaitkeviciene G, Kanerva J, Schmiegelow K. Methotrexate polyglutamate levels and co-distributions in childhood acute lymphoblastic leukemia maintenance therapy. Cancer Chemother Pharmacol 2018; 83:53-60. [PMID: 30324220 DOI: 10.1007/s00280-018-3704-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2018] [Accepted: 10/10/2018] [Indexed: 01/14/2023]
Abstract
PURPOSE Methotrexate polyglutamates (MTXpg) facilitate incorporation of thioguanine nucleotides into DNA (DNA-TG, the primary cytotoxic thiopurine metabolite and outcome determinant in MTX/6-mercaptopurine treatment of childhood ALL). We hypothesized that mapping erythrocyte levels of MTXpg with 1-6 glutamates and their associations with DNA-TG formation would facilitate future guidelines for maintenance therapy dosing. METHODS AND RESULTS Summed MTX with 1-6 glutamates resolved by LCMS [median (interquartile): 5.47 (3.58-7.69) nmol/mmol hemoglobin] was in agreement with total MTX by radio ligand assay. In 16,389 blood samples from 1426 ALL maintenance therapy patients, MTXpg3 21.0 (15.2-27.4)% was the predominant metabolite, and MTXpg1 (the maternal drug) constituted 38.6 (27.2-50.2)% of MTXpg1-6. All subsets correlated; the strongest associations were between metabolites with similar polyglutamate lengths. Correlations of MTXpg1 with MTXpg2 and MTXpg3,4,5,6 were rs = 0.68 and rs = 0.25-0.42, respectively. Intercorrelations of MTXpg3,4,5,6 were all rs ≥ 0.51. MTXpg4 accounted for 29.8 (24.7-33.3)% of MTXpg3-6, yet explained 96% of the summed MTXpg3-6 variation. MTXpg1-4, MTXpg1-6, MTXpg2-6 and MTXpg3 were all associated with DNA-TG levels (p < 0.00001), but collinearity precluded identification of the most informative subset. CONCLUSIONS Measuring erythrocyte MTXpg4 simplifies and can replace longer chain MTXpg monitoring. Resolving individual MTXpg identifies samples that are unsuitable for dose guidance due to high levels of MTXpg1 remaining in the plasma fraction because of recent MTX intake. All tested MTXpg subsets correlated with DNA-TG and may be used for ALL maintenance therapy dose adjustments, but the most informative subset remains to be identified.
Collapse
Affiliation(s)
- Jacob Nersting
- Department of Pediatrics and Adolescent Medicine, Rigshospitalet, University of Copenhagen, Blegdamsvej 9, 2100, Copenhagen, Denmark.
| | - Stine Nygaard Nielsen
- Department of Pediatrics and Adolescent Medicine, Rigshospitalet, University of Copenhagen, Blegdamsvej 9, 2100, Copenhagen, Denmark
| | - Kathrine Grell
- Department of Pediatrics and Adolescent Medicine, Rigshospitalet, University of Copenhagen, Blegdamsvej 9, 2100, Copenhagen, Denmark.,Section of Biostatistics, Department of Public Health, University of Copenhagen, Copenhagen, Denmark
| | - Maria Paerregaard
- Department of Pediatrics and Adolescent Medicine, Rigshospitalet, University of Copenhagen, Blegdamsvej 9, 2100, Copenhagen, Denmark
| | - Jonas Abrahamsson
- Department of Pediatrics, Institution for Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Bendik Lund
- Department of Pediatrics, St. Olavs Hospital, Trondheim University Hospital, Trondheim, Norway
| | | | | | | | - Jukka Kanerva
- Children's Hospital, Helsinki University Central Hospital, University of Helsinki, Helsinki, Finland
| | - Kjeld Schmiegelow
- Department of Pediatrics and Adolescent Medicine, Rigshospitalet, University of Copenhagen, Blegdamsvej 9, 2100, Copenhagen, Denmark.,Institute of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark
| | | |
Collapse
|
13
|
Silva MF, Ribeiro C, Gonçalves VMF, Tiritan ME, Lima Á. Liquid chromatographic methods for the therapeutic drug monitoring of methotrexate as clinical decision support for personalized medicine: A brief review. Biomed Chromatogr 2018; 32:e4159. [PMID: 29226354 DOI: 10.1002/bmc.4159] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2017] [Revised: 11/22/2017] [Accepted: 11/29/2017] [Indexed: 01/24/2023]
Abstract
Methotrexate (MTX) is an antifolate drug used for several diseases. Depending on the disease, MTX can be administered at low dose (LDMTX) in some autoimmune diseases, like rheumatoid arthritis, or at high dose (HDMTX) in some cancers, such as acute lymphoblastic leukemia. After absorption, MTX is metabolized in the liver to 7-hydroxymethotrexate and in the intestine to 2,4-diamino-N10-methylpteroic acid (DAMPA). Moreover, inside red blood cells, MTX is converted to active metabolites, MTX polyglutamates (MTXPGs), contributing to its pharmacodynamics. Owing to its narrow therapeutic range, and inter- and intra-patient variability, either noneffectiveness and/or toxicity may occur. Because of the existence of a relationship between drug therapeutic outcome and its systemic concentration, therapeutic drug monitoring (TDM) may ensure the effectiveness and safety of MTX use. In order to monitor the optimization of patient clinical response profile, several analytical methods have been described for TDM in biological samples. These include liquid chromatography (LC) coupled with ultraviolet detection, fluorescence detection or mass spectrometry, each one presenting advantages and drawbacks. This paper reviews the most commonly used techniques for sample preparation and critically discusses the current LC methods applied for the TDM of MTX in biological samples, at LDMTX and HDMTX.
Collapse
Affiliation(s)
- Mónica Francisco Silva
- CESPU, Instituto de Investigação e Formação Avançada em Ciências e Tecnologias da Saúde, Rua Central de Gandra, Gandra, PRD, Portugal.,Faculdade de Medicina da Universidade de Coimbra, R. Larga, Coimbra, Portugal
| | - Cláudia Ribeiro
- CESPU, Instituto de Investigação e Formação Avançada em Ciências e Tecnologias da Saúde, Rua Central de Gandra, Gandra, PRD, Portugal.,Centro Interdisciplinar de Investigação Marinha e Ambiental, Universidade do Porto, Rua dos Bragas, Porto, Portugal
| | - Virgínia M F Gonçalves
- CESPU, Instituto de Investigação e Formação Avançada em Ciências e Tecnologias da Saúde, Rua Central de Gandra, Gandra, PRD, Portugal
| | - Maria Elizabeth Tiritan
- CESPU, Instituto de Investigação e Formação Avançada em Ciências e Tecnologias da Saúde, Rua Central de Gandra, Gandra, PRD, Portugal.,Centro Interdisciplinar de Investigação Marinha e Ambiental, Universidade do Porto, Rua dos Bragas, Porto, Portugal.,Laboratório de Química Orgânica e Farmacêutica, Departamento de Ciências Químicas, Faculdade de Farmácia, Universidade do Porto, Rua de Jorge Viterbo Ferreira, Porto, Portugal
| | - Áurea Lima
- CESPU, Instituto de Investigação e Formação Avançada em Ciências e Tecnologias da Saúde, Rua Central de Gandra, Gandra, PRD, Portugal.,Grupo de Oncologia Molecular e Patologia Viral, Centro de Investigação, Instituto Português de Oncologia do Porto, Rua Dr. António Bernardino de Almeida, Porto, Portugal.,Hospital de Santo António, Centro Hospitalar do Porto, E.P.E. Largo do Prof. Abel Salazar, Porto, Portugal
| |
Collapse
|
14
|
Patel H, Giri P, Ghoghari A, Delvadia P, Syed M, Srinivas NR. Review of the bioanalytical methods for the determination of methotrexate and its metabolites inin vitro, preclinical and clinical studies: Case studies and perspectives. Biomed Chromatogr 2016; 31. [DOI: 10.1002/bmc.3849] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2016] [Revised: 08/31/2016] [Accepted: 09/06/2016] [Indexed: 12/18/2022]
Affiliation(s)
| | | | | | | | - Muzeeb Syed
- Department of Pharmacy, Faculty of Health and Medical Sciences; University of Copenhagen; Copenhagen Denmark
| | | |
Collapse
|
15
|
Becker ML. Using Methotrexate Metabolites to Make Clinical Decisions in JIA. CURRENT TREATMENT OPTIONS IN RHEUMATOLOGY 2015. [DOI: 10.1007/s40674-015-0028-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
|
16
|
Funk RS, van Haandel L, Leeder JS, Becker ML. Folate depletion and increased glutamation in juvenile idiopathic arthritis patients treated with methotrexate. Arthritis Rheumatol 2015; 66:3476-85. [PMID: 25186097 DOI: 10.1002/art.38865] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2014] [Accepted: 08/26/2014] [Indexed: 11/11/2022]
Abstract
OBJECTIVE Folates exist as a fluctuating pool of polyglutamated metabolites that may serve as a clinical marker of methotrexate (MTX) activity. This study was undertaken to evaluate circulating folate content and folate polyglutamate distribution in juvenile idiopathic arthritis (JIA) patients and in a cell culture model based on MTX exposure and folate supply. METHODS Blood, plasma, and red blood cell (RBC) measurements of MTX and folates were obtained from previously published data sets and an additional analysis of JIA patients receiving MTX (n = 98) and those not receiving MTX (n = 78). Erythroblastoid cells maintained in culture were exposed to MTX and grown under varying levels of folic acid supplementation. Samples were analyzed for cellular folate and MTX content. RESULTS Circulating folate levels were lower in JIA patients receiving MTX, with reduced levels of blood, plasma, and RBC 5-methyl-tetrahydrofolate (5mTHF) (P < 0.0001). Average polyglutamate chain length (Gluavg ) of RBC 5mTHF was elevated in JIA patients receiving MTX (median ± interquartile range 5.63 ± 0.15 versus 5.54 ± 0.11 in those not receiving MTX; P < 0.001) and correlated with both RBC MTX accumulation (P = 0.02) and reduced plasma 5mTHF levels (P = 0.008). MTX exposure and folate deprivation in erythroblastoid cells resulted in a depletion of bioactive folate species that was associated with a shift to higher Gluavg values for several species, most notably tetrahydrofolate (THF) and 5,10-methylene-tetrahydrofolate (CH2 THF). Increased Gluavg resulted from the depletion of short-chain and the accumulation of long-chain glutamate species. CONCLUSION Our findings indicate that folate content and polyglutamate distribution are responsive markers of MTX activity and folate supply in vivo and in vitro, and may provide novel clinical markers of pharmacologic activity of MTX.
Collapse
Affiliation(s)
- Ryan S Funk
- Children's Mercy Kansas City, Kansas City, Missouri and the University of Kansas Medical Center, Kansas City, Kansas
| | | | | | | |
Collapse
|
17
|
Bluett J, Riba-Garcia I, Hollywood K, Verstappen SMM, Barton A, Unwin RD. A HPLC-SRM-MS based method for the detection and quantification of methotrexate in urine at doses used in clinical practice for patients with rheumatological disease: a potential measure of adherence. Analyst 2015; 140:1981-7. [DOI: 10.1039/c4an02321h] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
A novel assay to measure adherence to low-dose oral methotrexate.
Collapse
Affiliation(s)
- J. Bluett
- Arthritis Research UK Centre for Genetics and Genomics
- Institute of Inflammation and Repair
- The University of Manchester
- Manchester
- UK
| | - I. Riba-Garcia
- Centre for Advanced Discovery and Experimental Therapeutics (CADET)
- Central Manchester University Hospitals NHS Foundation Trust
- Manchester Academic Health Sciences Centre
- Manchester
- UK
| | - K. Hollywood
- Centre for Advanced Discovery and Experimental Therapeutics (CADET)
- Central Manchester University Hospitals NHS Foundation Trust
- Manchester Academic Health Sciences Centre
- Manchester
- UK
| | - S. M. M. Verstappen
- Arthritis Research UK Centre for Epidemiology
- Centre for Musculoskeletal Research
- The University of Manchester
- Manchester
- UK
| | - A. Barton
- Arthritis Research UK Centre for Genetics and Genomics
- Institute of Inflammation and Repair
- The University of Manchester
- Manchester
- UK
| | - R. D. Unwin
- Centre for Advanced Discovery and Experimental Therapeutics (CADET)
- Central Manchester University Hospitals NHS Foundation Trust
- Manchester Academic Health Sciences Centre
- Manchester
- UK
| |
Collapse
|
18
|
Using Fluorescence Polarization Immunoassay for Determination of Erythrocyte Methotrexate Polyglutamates, a Quick and Easy Test? Ther Drug Monit 2014; 36:819-23. [DOI: 10.1097/ftd.0000000000000085] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
19
|
den Boer E, de Rotte MC, Pluijm SM, Heil SG, Hazes JM, de Jonge R. Determinants of Erythrocyte Methotrexate Polyglutamate Levels in Rheumatoid Arthritis. J Rheumatol 2014; 41:2167-78. [DOI: 10.3899/jrheum.131290] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Objective.Low-dose methotrexate (MTX) is the anchor drug in the treatment for rheumatoid arthritis (RA). Response to MTX is related to the intracellular MTX-polyglutamate (MTX-PG) levels and little is known about its determinants. We aimed to define the determinants of erythrocyte MTX-PG concentrations in 2 prospective cohorts of patients with RA.Methods.Patients with RA treated with MTX from 2 longitudinal cohorts were included: 93 from the MTX-R study (Rotterdam, the Netherlands derivation cohort), and 247 from the treatment in Rotterdam Early Arthritis Cohort study (validation cohort). MTX-PG concentrations were measured at 3 months of treatment using liquid chromatography/mass spectrometry. The MTX-PG were used as outcome measure. Various sociodemographic, clinical, biochemical, and genetic factors were assessed at baseline. Associations with MTX-PG levels were analyzed using multivariate regression analysis.Results.Age was positively associated with MTX-PG1 (stβ 0.23, p = 0.033) and total MTX-PG (stβ 0.23, p = 0.018) in the derivation cohort, and with all MTX-PG in the validation cohort (MTX-PG1: stβ 0.13, p = 0.04; MTX-PG2: stβ 0.21, p = 0.001; MTX-PG3: stβ 0.22, p < 0.001; MTX-PG4+5: stβ 0.25, p < 0.001; and total MTX-PG: stβ 0.32, p < 0.001). Erythrocyte folate levels were positively associated with MTX-PG3 (stβ 0.3, p = 0.021) and total MTX-PG levels (stβ 0.32, p = 0.022) in the derivation cohort, which was replicated for MTX-PG3 (stβ 0.15, p = 0.04) in the validation cohort. Patients with the folylpolyglutamate synthase (FPGS) rs4451422 wild-type genotype had higher concentrations of MTX-PG3 (p < 0.05), MTX-PG4+5 (p < 0.05), and total MTX-PG (p < 0.05) in both cohorts. In the combined cohort, MTX dose was positively associated with levels of MTX-PG3 (stβ 0.23, p < 0.001), MTX-PG4+5 (stβ 0.30, p < 0.001), and total MTX-PG (stβ 0.20, p = 0.002), but negatively associated with MTX-PG2 levels (stβ −0.22, p < 0.001).Conclusion.Our prospective study shows that higher age, higher MTX dose, higher erythrocyte folate status, and the FPGS rs4451422 wild-type genotype are associated with higher MTX-PG concentrations. While only up to 21% of interpatient variability can be explained by these determinants, this knowledge may aid in the development of personalized treatment in RA.
Collapse
|
20
|
Hawwa AF, AlBawab A, Rooney M, Wedderburn LR, Beresford MW, McElnay JC. A novel dried blood spot-LCMS method for the quantification of methotrexate polyglutamates as a potential marker for methotrexate use in children. PLoS One 2014; 9:e89908. [PMID: 24587116 PMCID: PMC3934981 DOI: 10.1371/journal.pone.0089908] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2013] [Accepted: 01/24/2014] [Indexed: 01/08/2023] Open
Abstract
Objective Development and validation of a selective and sensitive LCMS method for the determination of methotrexate polyglutamates in dried blood spots (DBS). Methods DBS samples [spiked or patient samples] were prepared by applying blood to Guthrie cards which was then dried at room temperature. The method utilised 6-mm disks punched from the DBS samples (equivalent to approximately 12 µl of whole blood). The simple treatment procedure was based on protein precipitation using perchloric acid followed by solid phase extraction using MAX cartridges. The extracted sample was chromatographed using a reversed phase system involving an Atlantis T3-C18 column (3 µm, 2.1×150 mm) preceded by Atlantis guard column of matching chemistry. Analytes were subjected to LCMS analysis using positive electrospray ionization. Key Results The method was linear over the range 5–400 nmol/L. The limits of detection and quantification were 1.6 and 5 nmol/L for individual polyglutamates and 1.5 and 4.5 nmol/L for total polyglutamates, respectively. The method has been applied successfully to the determination of DBS finger-prick samples from 47 paediatric patients and results confirmed with concentrations measured in matched RBC samples using conventional HPLC-UV technique. Conclusions and Clinical Relevance The methodology has a potential for application in a range of clinical studies (e.g. pharmacokinetic evaluations or medication adherence assessment) since it is minimally invasive and easy to perform, potentially allowing parents to take blood samples at home. The feasibility of using DBS sampling can be of major value for future clinical trials or clinical care in paediatric rheumatology.
Collapse
Affiliation(s)
- Ahmed F. Hawwa
- Clinical and Practice Research Group, School of Pharmacy, Queen's University Belfast, Belfast, United Kingdom
- Aston Pharmacy School, Aston University, Birmingham, United Kingdom
| | - AbdelQader AlBawab
- Clinical and Practice Research Group, School of Pharmacy, Queen's University Belfast, Belfast, United Kingdom
| | - Madeleine Rooney
- School of Medicine, Queen's University Belfast and Musgrave Park Hospital, Belfast, United Kingdom
| | - Lucy R. Wedderburn
- Institute of Child Health, University College London, London, United Kingdom
- Arthritis Research UK Centre for Adolescent Rheumatology at University College London, University College London Hospital and Great Ormond Street Hospital NHS Foundation Trust, London, United Kingdom
| | - Michael W. Beresford
- Department of Women's and Children's Health, University of Liverpool, The Alder Hey Children’s NHS Foundation Trust, Liverpool, United Kingdom
| | - James C. McElnay
- Clinical and Practice Research Group, School of Pharmacy, Queen's University Belfast, Belfast, United Kingdom
- * E-mail:
| |
Collapse
|
21
|
Funk RS, van Haandel L, Becker ML, Leeder JS. Low-dose methotrexate results in the selective accumulation of aminoimidazole carboxamide ribotide in an erythroblastoid cell line. J Pharmacol Exp Ther 2013; 347:154-63. [PMID: 23887097 DOI: 10.1124/jpet.113.206672] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Therapeutic and toxic response to low-dose methotrexate (MTX) in the treatment of autoimmune disease continues to be highly variable, resulting in a critical need to identify predictive biomarkers of response. Biomarker development has been hampered by an incomplete understanding of the molecular pharmacology of low-dose MTX. To address this issue, accumulation of the substrates for aminoimidazole carboxamide ribonucleotide transformylase (AICART) and thymidylate synthase (TS) was measured as markers of pharmacological activity of MTX in an erythroblastoid cell line. A 115-fold increase in the AICART substrate and anti-inflammatory mediator, 5-aminoimidazole-4-carboxamide-1-β-d-ribofuranosyl 5'-monophosphate (ZMP), was observed following exposure to 10 nM MTX but subsequently decreased with increasing MTX concentrations, declining to baseline levels with 1000 nM MTX. In contrast, the TS substrate, 2'-deoxyuridine 5'-monophosphate disodium salt (dUMP), displayed concentration-dependent accumulation, increasing 29-, 342-, and 471-fold over baseline with 10, 100, and 1000 nM MTX, respectively. Cellular levels of dUMP correlated with levels of the parent drug (MTX-PG1; r = 0.66, P < 0.001) and its polyglutamates (MTX-PG2-6) (r = 0.81, P < 0.001), whereas cellular levels of ZMP were only moderately correlated with MTX-PG1 (r = 0.34, P < 0.01). In contrast, accumulation of ZMP at 10 nM MTX was associated with a 2.9-fold increase in the AICART inhibitor dihydrofolate (DHF), represented primarily by long-chain DHF polyglutamates. Selectivity, defined as the ratio of ZMP to dUMP, was maximal following exposure to 6 nM MTX. Characterizing the range of MTX concentrations that selectively promote ZMP accumulation while preserving pyrimidine biosynthesis may lead to optimization of low-dose MTX therapy.
Collapse
Affiliation(s)
- Ryan S Funk
- Division of Clinical Pharmacology and Therapeutic Innovation, Children's Mercy Hospital, Kansas City, Missouri (R.S.F., L.v.H., M.L.B., J.S.L.); and Schools of Medicine (M.L.B., J.S.L.) and Pharmacy (J.S.L.), University of Missouri-Kansas City, Kansas City, Missouri
| | | | | | | |
Collapse
|
22
|
Measuring methotrexate polyglutamates in red blood cells: a new LC-MS/MS-based method. Anal Bioanal Chem 2012; 405:1673-81. [DOI: 10.1007/s00216-012-6581-7] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2012] [Revised: 11/09/2012] [Accepted: 11/14/2012] [Indexed: 10/27/2022]
|
23
|
Determination of erythrocyte methotrexate polyglutamates by liquid chromatography/tandem mass spectrometry after low-dose methotrexate therapy in Chinese patients with rheumatoid arthritis. J Chromatogr B Analyt Technol Biomed Life Sci 2012; 907:41-8. [DOI: 10.1016/j.jchromb.2012.08.032] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2012] [Revised: 08/20/2012] [Accepted: 08/24/2012] [Indexed: 11/22/2022]
|
24
|
A U–HPLC–ESI–MS/MS–Based Stable Isotope Dilution Method for the Detection and Quantitation of Methotrexate in Plasma. Ther Drug Monit 2012; 34:432-9. [DOI: 10.1097/ftd.0b013e31825bb368] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
|
25
|
van Haandel L, Becker ML, Williams TD, Stobaugh JF, Leeder JS. Comprehensive quantitative measurement of folate polyglutamates in human erythrocytes by ion pairing ultra-performance liquid chromatography/tandem mass spectrometry. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2012; 26:1617-1630. [PMID: 22693118 DOI: 10.1002/rcm.6268] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
RATIONALE The erythrocyte folate pool is reflective of an individual's long-term folate status; however, comprehensive quantitative determination of the various folate isoforms including polyglutamation (Glu(n)) status has posed an analytical problem. Factors complicating such analysis are the absence of authentic (isotope-labeled) standards and the large number of potential analytes. The present work presents high-throughput analytical methodology for the indirect comprehensive quantitation of the erythrocyte folate pool with commercially available standards. METHODS The erythrocyte folate pool was determined comprehensively by utilizing a cascade of three complementary ultra-performance liquid chromatography (UPLC) tandem mass spectrometry (MS/MS) assays. In a first assay utilizing ion-pairing UPLC/MS/MS the relative (%) polyglutamation distribution (Glu(3-10)) of 5-methyltetrahydrofolate, tetrahydrofolate and 5-formyltetrahydrofolate is determined in a thermal extract obtained from packed erythrocytes, not requiring analytical standards. Quantitation of the erythrocyte folate pool was accomplished by performing two additional stable isotope dilution UPLC/MS/MS assays to determine whole blood and plasma folate content, utilizing commercially available [(13)C(5)]-labeled analogs of the Glu(1) analytes. Based on the values provided by each individual assay the comprehensive erythrocyte folate content could be calculated. RESULTS The various assays have been validated for intra- and inter-run precision, accuracy, linearity and are robust. The method was sensitive enough to measure the comprehensive erythrocyte folate distribution in a Down's syndrome patient with extremely low folate, bearing the C677T mutation in the gene encoding for methylenetetrahydrofolate reductase. CONCLUSIONS The erythrocyte folate pool can be comprehensively quantitated by running three complementary UPLC/MS/MS assays. The present assays are robust and allow for high-throughput analysis. The method can be utilized to support larger investigations that investigate the relationship between folate isoform and polyglutamation distribution and disease pathogenesis.
Collapse
Affiliation(s)
- Leon van Haandel
- Division of Clinical Pharmacology and Medical Toxicology, Children's Mercy Hospitals and Clinics, Kansas City, MO 64108, USA
| | | | | | | | | |
Collapse
|
26
|
Measurement of methotrexate polyglutamates in human erythrocytes by ion-pair UPLC-MS/MS. Bioanalysis 2012; 3:2783-96. [PMID: 22185278 DOI: 10.4155/bio.11.288] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
BACKGROUND Low-dose methotrexate is used for the treatment of rheumatoid arthritis and juvenile idiopathic arthritis, but its effectiveness greatly varies between individuals. Therapeutic drug monitoring of intracellular methotrexate metabolites, the γ-polyglutamates (MTXGlu(n)), in human erythrocytes has shown promise in providing a basis for individualization of therapy. RESULTS This work presents expedient methodology for the analysis of MTXGlu(1-7) in human erythrocytes by ion-pair UPLC with detection by tandem MS (UPLC-ESI-MS/MS). The use of N,N-dimethylheptylamine as an ion-pair agent was found to be favorable over others. Thermal extraction of erythrocyte lysates provides a simple one-step extraction procedure. The entire chromatographic run time is 6 min and the assay was validated within the therapeutic range of these metabolites CONCLUSION The developed sample preparation procedure in combination with ion-pair UPLC-ESI-MS/MS analysis allowed for expedient quantitation of MTXGlu(1-7) in human erythrocytes. The rapid analysis time would enable therapeutic drug monitoring of MTXGlu(1-7) in the clinic.
Collapse
|
27
|
Red blood cell folate concentrations and polyglutamate distribution in juvenile arthritis. Pharmacogenet Genomics 2012; 22:236-46. [DOI: 10.1097/fpc.0b013e3283500202] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
|
28
|
|
29
|
Meesters RJW, den Boer E, de Jonge R, Lindemans J, Luider TM. Assessment of intracellular methotrexate and methotrexate-polyglutamate metabolite concentrations in erythrocytes by ultrafast matrix-assisted laser desorption/ionization triple quadrupole tandem mass spectrometry. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2011; 25:3063-3070. [PMID: 21953961 DOI: 10.1002/rcm.5202] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
A new ultrafast quantitative and high-throughput mass spectrometric method using matrix-assisted laser desorption/ionization triple quadrupole tandem mass spectrometry has been developed and validated for determination of intracellular erythrocyte concentrations of the antifolate drug methotrexate (MTX) and its polyglutamate metabolites. The method consists of a solid-phase extraction of MTX and MTX-polyglutamate metabolites from deproteinized erythrocyte lysates spiked with aminopterin as internal standard. The newly developed method was validated according to the most recent FDA guidelines on linearity, recovery, within-run and between-run accuracy and precision and stability of the analytes. The low limit of quantification (LLOQ) was 10 nmol/L for all analytes while the limit of detection (LOD) determined at a signal-to-noise (S/N) ratio = 3:1 in drug- free erythrocyte lysate was on average 0.3 nmol/L. After validation, the new method was used in the measurement of intracellular erythrocyte concentrations of MTX and MTX-polyglutamate metabolites (MTXPG2 to MTXPG7) in packed human erythrocyte samples collected from patients with rheumatoid arthritis receiving low-dose oral methotrexate therapy. Mean (SD) intracellular erythrocyte concentrations observed in patient samples were 12.8 (12.6), 12.4 (9.4), 44.4 (30.0), 33.6 (35.9) and 9.4 (8.2) nmol/L for MTX to MTXPG5, respectively, in 10(6) erythrocytes. The highest observed glutamylation degree of MTX was MTXPG5, the very long chain MTX-polyglutamate metabolites MTXPG6 and MTXPG7 were not detected in the packed erythrocyte pellets collected from rheumatoid arthritis patients.
Collapse
Affiliation(s)
- Roland J W Meesters
- Department of Neurology, University Medical Center Rotterdam (ErasmusMC), Rotterdam, The Netherlands.
| | | | | | | | | |
Collapse
|
30
|
Abstract
For a select number of drugs, proper management of patients includes monitoring serum or plasma concentrations of the drugs and adjusting the doses accordingly - this practice is referred to as therapeutic drug monitoring (TDM). The need for TDM arises when pharmacokinetic variability of drugs is not easily accounted for by common clinical parameters. Many chemotherapeutic drugs have large interindividual variability, yet TDM is not commonplace in chemotherapy management. This review will discuss pharmacokinetics in the context of chemotherapeutic drugs, examine the few instances where TDM is currently used in the field of oncology and propose other drugs where TDM might be useful for dose adjustments in the management of chemotherapy.
Collapse
|
31
|
Verdier MC, Tribut O, Bodeau S, Rihouey D, Bentué-Ferrer D. Suivi thérapeutique pharmacologique du méthotrexate à faible dose dans les maladies inflammatoires. Therapie 2011; 66:63-72. [DOI: 10.2515/therapie/2011002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2010] [Accepted: 11/26/2010] [Indexed: 11/20/2022]
|
32
|
Becker ML, Gaedigk R, van Haandel L, Thomas B, Lasky A, Hoeltzel M, Dai H, Stobaugh J, Leeder JS. The effect of genotype on methotrexate polyglutamate variability in juvenile idiopathic arthritis and association with drug response. ACTA ACUST UNITED AC 2010; 63:276-85. [DOI: 10.1002/art.30080] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
|
33
|
Becker ML, van Haandel L, Gaedigk R, Lasky A, Hoeltzel M, Stobaugh J, Leeder JS. Analysis of intracellular methotrexate polyglutamates in patients with juvenile idiopathic arthritis: effect of route of administration on variability in intracellular methotrexate polyglutamate concentrations. ACTA ACUST UNITED AC 2010; 62:1803-12. [PMID: 20191581 DOI: 10.1002/art.27434] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
OBJECTIVE Intracellular methotrexate (MTX) polyglutamates (MTXGlu) have been shown to be potentially useful biomarkers of clinical response in adult patients with rheumatoid arthritis. The present study was undertaken to measure intracellular MTXGlu concentrations in a cohort of patients with juvenile idiopathic arthritis (JIA) to determine the predictors of MTXGlu variability in these patients. METHODS Blood samples were obtained from patients with JIA who were being treated with a stable dose of MTX for >or=3 months. Clinical data were collected by chart review. Concentrations of MTXGlu(1-7) in red blood cell lysates were quantitated using an innovative ion-pairing chromatography procedure, with detection by mass spectrometry. RESULTS Patients with JIA from a single center (n = 99; mean +/- SD age 117.8 +/- 56.5 months, 69 female) were included in the analysis. The mean +/- SD dose of MTX was 0.51 +/- 0.25 mg/kg per week, with a median treatment duration of 18 months (interquartile range 3-156 months). MTX was administered subcutaneously in 66 patients (67%). Fifty-six patients (57%) had active arthritis at the time of the clinic visit. Total intracellular MTXGlu (MTXGlu(TOT)) concentrations varied 40-fold, with a mean +/- SD total concentration of 85.8 +/- 48.4 nmoles/liter. Concentrations of each MTXGlu subtype (MTXGlu(1-7)) were measured individually and as a percentage of MTXGlu(TOT) in each patient. MTXGlu(3) was the most prominent subtype identified, comprising 42% of MTXGlu(TOT), and the interindividual variability in the concentration of MTXGlu(3) was the most highly correlated with that of MTXGlu(TOT) (r = 0.96). The route of MTX administration was significantly associated with MTXGlu(1-5) subtypes; higher concentrations of MTXGlu(1 + 2) were observed in patients receiving oral doses of MTX, whereas higher concentrations of MTXGlu(3-5) were observed in patients receiving subcutaneous doses of MTX (P < 0.0001). CONCLUSION In this cohort of patients with JIA, the MTXGlu(TOT) concentration varied 40-fold. Individual MTXGlu metabolites (MTXGlu(1-7)), which have, until now, not been previously reported in patients with JIA, were detected. The route of MTX administration contributed to the variability in concentrations of MTXGlu(1-5).
Collapse
Affiliation(s)
- Mara L Becker
- Children's Mercy Hospital, Kansas City, Missouri, USA.
| | | | | | | | | | | | | |
Collapse
|