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Rao B H, Vincent PK, Nair P, Koshy AK, Venu RP. The preventive effect of tacrolimus on patients with post-endoscopic retrograde cholangiopancreatography pancreatitis. Clin Endosc 2022; 55:665-673. [PMID: 35915049 PMCID: PMC9539296 DOI: 10.5946/ce.2021.265] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/26/2021] [Accepted: 01/04/2022] [Indexed: 11/29/2022] Open
Abstract
Background/Aims In patients undergoing endoscopic retrograde cholangiopancreatography (ERCP), calcineurin activates zymogen, which results in pancreatitis. In this study, we aimed to determine the efficacy of tacrolimus, a calcineurin inhibitor, in preventing post-ERCP pancreatitis (PEP).
Methods This was a prospective pilot study in which patients who underwent ERCP received tacrolimus (4 mg in two divided doses); this was the Tac group. A contemporaneous cohort of patients was included as a control group. All patients were followed-up for PEP. PEP was characterized by worsening abdominal pain with an acute onset, elevated pancreatic enzymes, and a duration of hospital stay of more than 48 hours. Serum tacrolimus levels were measured immediately before the procedure in the Tac group.
Results There were no differences in the baseline characteristics between the Tac group (n=48) and the control group (n=51). Only four out of 48 patients (8.3%) had PEP in the Tac group compared to eight out of 51 patients (15.7%) who had PEP in the control group. The mean trough tacrolimus level in patients who developed PEP was significantly lower (p<0.05).
Conclusions Oral tacrolimus at a cumulative dose of 4 mg safely prevents PEP. Further randomized controlled studies are warranted to establish the role of tacrolimus in this context.
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Affiliation(s)
- Harshavardhan Rao B
- Department of Gastroenterology, Amrita Institute of Medical Sciences, Kochi, India
| | - Paul K Vincent
- Department of Gastroenterology, Amrita Institute of Medical Sciences, Kochi, India
| | - Priya Nair
- Department of Gastroenterology, Amrita Institute of Medical Sciences, Kochi, India
| | - Anoop K Koshy
- Department of Gastroenterology, Amrita Institute of Medical Sciences, Kochi, India
| | - Rama P Venu
- Department of Gastroenterology, Amrita Institute of Medical Sciences, Kochi, India
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2
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Lolita L, Zheng M, Zhang X, Han Z, Tao J, Fei S, Wang Z, Guo M, Yang H, Ju X, Tan R, Wei JF, Gu M. The Genetic Polymorphism of CYP3A4 rs 2242480 is Associated with Sirolimus Trough Concentrations Among Adult Renal Transplant Recipients. Curr Drug Metab 2020; 21:1052-1059. [PMID: 33115392 DOI: 10.2174/1389200221999201027203401] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2020] [Revised: 09/02/2020] [Accepted: 09/16/2020] [Indexed: 12/28/2022]
Abstract
BACKGROUND The large interindividual variability in the genetic polymorphisms of sirolimus (SIR)- metabolizing enzymes, transporters, and receptors can lead to qualitatively and quantitatively distinct therapeutic responses. OBJECTIVE We examined the impact of numerous candidate single-nucleotide polymorphisms (SNPs) involved in the trough concentration of SIR-based immunosuppressant regimen. METHODS This is a retrospective, long-term cohort study involving 69 renal allograft recipients. Total DNA was isolated from recipient blood samples and trough SIR concentrations were measured by microparticle enzyme immunoassay. Genome sequence reading was targeted based on next-generation sequencing. The association of tagger SNPs to SIR trough concentrations with non-genetic covariate adjusting was analyzed using logistic regression. RESULTS A total of 300 SNPs were genotyped in the recipient DNA samples using target sequencing analysis. Only the SNP of CYP3A4 (Ch7: 99361466 C>T, rs2242480) had a significantly higher association with SIR trough concentration as compared to the other 36 tagger SNPs. The mean trough SIR concentration of patients in the CYP3A4 rs2242480-CC group was more significant compared to that of the CYP3A4 rs2242480-TC and TT group, respectively 533.3; 157.4 and 142.5 (ng/ml)/mg/kg, P<0.0001. After adjusting the SNPs, there was no significant association between clinical factors such as age, follow-up period, the incidence of delayed graft function, immunosuppression protocol, and sex with SIR trough concentration. CONCLUSION These findings indicated a significant association of polymorphism in the CYP3A4 (Ch7: 99361466 C>T, rs2242480) with SIR trough concentration after 1-year administration in patients who have undergone kidney transplantation.
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Affiliation(s)
- Lolita Lolita
- Research Division of Clinical Pharmacology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Ming Zheng
- Department of Urology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Xiang Zhang
- Department of Urology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Zhijian Han
- Department of Urology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Jun Tao
- Department of Urology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Shuang Fei
- Department of Urology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Zijie Wang
- Department of Urology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Miao Guo
- Research Division of Clinical Pharmacology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Haiwei Yang
- Department of Urology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Xiaobing Ju
- Department of Urology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Ruoyun Tan
- Department of Urology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Ji-Fu Wei
- Research Division of Clinical Pharmacology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Min Gu
- Department of Urology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China
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Nakazawa R, Yoshiike M, Nozawa S, Aida K, Katsuoka Y, Fujimoto E, Yazawa M, Kikuchi E, Shibagaki Y, Sasaki H. Clinically useful limited sampling strategy to estimate area under the concentration-time curve of once-daily tacrolimus in adult Japanese kidney transplant recipients. PLoS One 2019; 14:e0225878. [PMID: 31825991 PMCID: PMC6905578 DOI: 10.1371/journal.pone.0225878] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2019] [Accepted: 11/14/2019] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND An extended-release, once-daily, oral formulation of tacrolimus is currently used after kidney transplantation as a substitute for the conventional twice-daily formulation. The purpose of this study was to provide a limited sampling strategy with minimum and optimum sampling points to predict the tacrolimus area under the concentration-time curve (AUC) after administration of once-daily tacrolimus in de novo adult kidney transplant patients. METHODS A total of 36 adult Japanese kidney transplant patients receiving once-daily tacrolimus were included: 31 were allocated to a study group to develop limited sampling strategy (LSS) model equations based on multiple stepwise linear regression analysis, and 5 were allocated to a validation group to estimate the precision of the LSS equations developed by the study group. Twelve-hour AUC (AUC0-12) was calculated by the trapezoidal rule, and the relationship between individual concentration points and AUC0-12 were determined by multiple linear regression analysis. The coefficient of determination (R2) was used to assess the goodness-of-fit of the regression models. Three error indices (mean error, mean absolute error, and root mean squared prediction error) were calculated to evaluate predictive bias, accuracy, and precision, respectively. Quality of the statistical models was compared with Akaike's information criterion (AIC). RESULTS A four-point model using C0, C2, C4 and C6 gave the best fit to predict AUC0-12 (R2 = 0.978). In the three- and two-point models, the best fits were at time points C2, C4, and C6 (R2 = 0.973), and C2 and C6 (R2 = 0.962), respectively. All three models reliably estimated tacrolimus AUC0-12, consistent with evaluations by the three error indices and Akaike's information criterion. Practically, the two-point model with C2 and C6 was considered to be the best combination, providing a highly accurate prediction and the lowest blood sampling frequency. CONCLUSIONS The two-point model with C2 and C6 may be valuable in reducing the burden on patients, as well as medical costs, for once-daily tacrolimus monitoring.
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Affiliation(s)
- Ryuto Nakazawa
- Department of Urology, St. Marianna University School of Medicine, Kawasaki, Japan
- * E-mail:
| | - Miki Yoshiike
- Department of Urology, St. Marianna University School of Medicine, Kawasaki, Japan
| | - Shiari Nozawa
- Department of Urology, St. Marianna University School of Medicine, Kawasaki, Japan
| | - Koichiro Aida
- Department of Urology, St. Marianna University School of Medicine, Kawasaki, Japan
| | - Yuichi Katsuoka
- Department of Urology, St. Marianna University School of Medicine, Kawasaki, Japan
| | - Eisuke Fujimoto
- Department of Urology, St. Marianna University School of Medicine, Kawasaki, Japan
| | - Masahiko Yazawa
- Division of Nephrology and Hypertension, Department of Internal Medicine, St. Marianna University School of Medicine, Kawasaki, Japan
| | - Eiji Kikuchi
- Department of Urology, St. Marianna University School of Medicine, Kawasaki, Japan
| | - Yugo Shibagaki
- Division of Nephrology and Hypertension, Department of Internal Medicine, St. Marianna University School of Medicine, Kawasaki, Japan
| | - Hideo Sasaki
- Department of Urology, St. Marianna University School of Medicine, Kawasaki, Japan
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Large-Scale Variability of Inpatient Tacrolimus Therapeutic Drug Monitoring at an Academic Transplant Center: A Retrospective Study. Ther Drug Monit 2018; 40:394-400. [DOI: 10.1097/ftd.0000000000000526] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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5
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Cho EJ, Ko DH, Lee W, Chun S, Lee HK, Min WK. Performance of the Dimension TAC assay and comparison of multiple platforms for the measurement of tacrolimus. J Clin Lab Anal 2017; 32:e22357. [PMID: 29148096 DOI: 10.1002/jcla.22357] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2017] [Accepted: 10/20/2017] [Indexed: 01/31/2023] Open
Abstract
BACKGROUND Therapeutic monitoring of tacrolimus is essential for reducing organ rejection and adverse effects. The measurement of tacrolimus in whole blood is taken by many automated platforms. We evaluated the analytical performance of the Dimension TAC assay, which is an upgraded reagent from the previous Dimension TACR assay. METHODS The evaluations involved determination of precision, linearity, detection capability, and reagent lot-to-lot variability between three lot numbers. Correlation studies were conducted using the Dimension TACR assay, Architect, Elecsys assay, and MassTrak LC-MS/MS. RESULTS The total coefficient of variation was below 10%. Acceptable linearity was observed in their respective reportable ranges. The limit of blank, limit of detection, and limit of quantification were 0.29, 0.47, and 0.81 ng/mL, respectively. Correlation analysis indicated that the Dimension TAC assay results were comparable to that of the Dimension TACR assay, Architect, and Elecsys results in liver and heart transplant patients. In kidney transplant patients, the Dimension TAC assay showed the poor correlation with Architect and Elecsys. The results from these assays were slightly higher than that of MassTrak. We found little lot-to-lot reagent variation among the reagents evaluated. CONCLUSION The overall analytical performance of the Dimension TAC assay is acceptable for therapeutic monitoring in clinical practice. Our study that compared different platforms may provide some useful information regarding which test method to use.
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Affiliation(s)
- Eun-Jung Cho
- Department of Laboratory Medicine, The Catholic University of Korea College of Medicine, Uijeongbu St. Mary's Hospital, Uijeongbu, Korea.,Department of Laboratory Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
| | - Dae-Hyun Ko
- Department of Laboratory Medicine, Hallym University College of Medicine, Dongtan Sacred Heart Hospital, Hwaseong, Korea
| | - Woochang Lee
- Department of Laboratory Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
| | - Sail Chun
- Department of Laboratory Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
| | - Hae-Kyung Lee
- Department of Laboratory Medicine, The Catholic University of Korea College of Medicine, Uijeongbu St. Mary's Hospital, Uijeongbu, Korea
| | - Won-Ki Min
- Department of Laboratory Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
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Impact of Laboratory Practices on Interlaboratory Variability in Therapeutic Drug Monitoring of Immunosuppressive Drugs. Ther Drug Monit 2015; 37:718-24. [DOI: 10.1097/ftd.0000000000000205] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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7
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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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8
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Abboudi H, Macphee IA. Individualized immunosuppression in transplant patients: potential role of pharmacogenetics. PHARMACOGENOMICS & PERSONALIZED MEDICINE 2012; 5:63-72. [PMID: 23226063 PMCID: PMC3513229 DOI: 10.2147/pgpm.s21743] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 06/16/2012] [Indexed: 12/29/2022]
Abstract
The immunosuppressive drugs used to prevent the rejection of transplanted organs have a narrow therapeutic index. Under treatment results in episodes of rejection leading to either damage or loss of the organ. Over immunosuppression increases the risk of infection and malignancy as well as drug specific complications including diabetes mellitus and nephrotoxicity. There is wide variation in the drug dose required to achieve target blood concentrations and there is often dissociation between pharmacokinetics and pharmacodynamics. Currently, immunosuppressive drug treatment is individualized based on a clinical assessment of the risk of rejection or toxicity. Therapeutic drug monitoring is routinely employed for several immunosuppressive drugs. Pharmacogenetics has the potential to complement therapeutic drug monitoring but clinical benefit has yet to be demonstrated. Novel biomarker-based approaches to risk stratification and pharmacodynamic monitoring are under development and are ready for clinical trials.
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Affiliation(s)
- Hamid Abboudi
- Division of Clinical Sciences, Renal Medicine, St George's, University of London, London, UK
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9
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Karapirli M, Kizilgun M, Yesilyurt O, Gul H, Kunak ZI, Akgul EO, Macit E, Cayci T, Gulcan Kurt Y, Aydin I, Yaren H, Seyrek M, Cakir E, Yaman H. Simultaneous determination of cyclosporine A, tacrolimus, sirolimus, and everolimus in whole-blood samples by LC-MS/MS. ScientificWorldJournal 2012; 2012:571201. [PMID: 22629148 PMCID: PMC3354445 DOI: 10.1100/2012/571201] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2011] [Accepted: 01/03/2012] [Indexed: 12/20/2022] Open
Abstract
Objectives. Cyclosporine A (CyA), tacrolimus (TRL), sirolimus (SIR), and everolimus (RAD) are immunosuppressive drugs frequently used in organ transplantation. Our aim was to confirm a robust sensitive and selective liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for determination of CyA, TRL, SIR, and RAD in whole-blood samples. Materials and Methods. We used an integrated online solid-phase extraction-LC-MS/MS system and atmospheric pressure ionization tandem mass spectrometry (API-MS/MS) in the multiple reaction monitoring (MRM) detection mode. CyA, TRL, SIR, and RAD were simultaneously analyzed in whole blood treated with precipitation reagent taken from transplant patients. Results. System performance parameters were suitable for using this method as a high-throughput technique in clinical practice. The high concentration of one analyte in the sample did not affect the concentration of other analytes. Total analytical time was 2.5 min, and retention times of all analytes were shorter than 2 minutes. Conclusion. This LC-MS/MS method can be preferable for therapeutic drug monitoring of these immunosuppressive drugs (CyA, TRL, SRL, and RAD) in whole blood. Sample preparation was too short and simple in this method, and it permits robust, rapid, sensitive, selective, and simultaneous determination of these drugs.
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Affiliation(s)
- Mustafa Karapirli
- Council of Forensic Medicine, Ankara Branch, Kecioren, 06018 Ankara, Turkey
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10
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Bajjoka I, Makowski C, Churchill D, Abouljoud M. Belatacept Post Kidney Transplantation. J Pharm Technol 2012. [DOI: 10.1177/875512251202800304] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Objective: To review the use of belatacept as an alternative to calcineurin inhibitor-based regimens for maintenance immunosuppression in renal transplant recipients. Data Sources: To provide an extensive overview of the pharmacology, pharmacokinetics, efficacy, and safety of belatacept, a MEDLINE/PubMed search (1980–December 2011) was performed for all articles evaluating belatacept's properties and patient outcomes, as well as abstracts from recent meetings, using key words belatacept, pharmacology, efficacy, pharmacokinetics, and safety. Study Selection/Data Extraction: Phase 2 and 3 studies in humans describing use, adverse reactions, pharmacology, pharmacokinetics, efficacy, and safety of belatacept were identified and reviewed. Other articles were identified through PubMed. Data Synthesis: Belatacept, a costimulation blocker, is a biologic recombinant fusion protein that has been shown to prevent acute cellular rejection in kidney transplant recipients and preserve renal function. It was recently approved by the FDA as an antirejection immunosuppressant agent for use in kidney transplant recipients. It is the first biologic agent used for maintenance immunosuppression. It acts as an antagonist to CD80 and CD86 receptors located on the surface of antigen presenting cells, thereby blocking CD28 T-cell activation and, thus, preventing acute rejection. In comparison with patients receiving other current therapies, patients on belatacept have demonstrated superior renal function with comparable outcomes in patient and graft survival. Conclusions: Belatacept has potential for use as an alternative to current maintenance immunosuppression regimens, with potentially fewer adverse effects.
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Affiliation(s)
- Iman Bajjoka
- IMAN BAJJOKA PharmD BCPS FCCP, Director, Transplant Clinical Research, Henry Ford Transplant Institute, Detroit, MI
| | - Charles Makowski
- CHARLES MAKOWSKI, PharmD Student, Eugene Applebaum School of Pharmacy, Wayne State University, Detroit
| | - Dennis Churchill
- DENNIS CHURCHILL, Medical Student, School of Medicine, Wayne State University
| | - Marwan Abouljoud
- MARWAN ABOULJOUD MD, Director, Henry Ford Transplant Institute, Detroit
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Morjana N, Yau H, Rea D, Ruttle D, Jones H, Siefring G, Christenson R. The Emit® 2000 Cyclosporine Specific Assay, Extended Range: development of an application protocol for the V-Twin® analyzer. Biotechnol Appl Biochem 2011; 58:476-82. [PMID: 22172110 DOI: 10.1002/bab.43] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2011] [Accepted: 07/13/2011] [Indexed: 11/12/2022]
Abstract
We evaluated a new protocol for measurement of cyclosporine A (CsA) 2 H after dose (C2) on the V-Twin® analyzer. Imprecision, recovery, and linearity were determined using CsA-spiked blood pools. Accuracy was evaluated using specimens from renal, cardiac, and liver transplant patients, and results were compared with those from liquid chromatography-tandem mass spectrometry (LC-MS/MS) and the Abbott TDx®/TDxFLx® assay. Cross-reactivity and interferences were assessed in the presence of 800 ng/mL CsA. Imprecision coefficients of variation were 3.3%-4.8% (within run) and 5.9%-8.7% (total). Recovery was within 10% of the expected values. Linearity was 350-2,000 ng/mL. Calibration was stable for ≥ 2 weeks. Method comparison showed regression statistics: V-Twin® = 1.01 × LC tandem MS + 36.1, r = 0.971; V-Twin® = 1.13 × Abbott - 92.4, r = 0.969. Metabolite cross-reactivity and interference (endogenous substances and drugs) were within ±10%. The C2 protocol on the V-Twin® analyzer provides acceptable assay performance and accurate determination of whole blood CsA drawn at 2 H after dose.
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Affiliation(s)
- Nihmat Morjana
- Siemens Healthcare Diagnostics Inc., Newark, DE 19702, USA.
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Optimal sampling strategy development methodology using maximum a posteriori Bayesian estimation. Ther Drug Monit 2011; 33:133-46. [PMID: 21383653 DOI: 10.1097/ftd.0b013e31820f40f8] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Maximum a posteriori Bayesian (MAPB) pharmacokinetic parameter estimation is an accurate and flexible method of estimating individual pharmacokinetic parameters using individual blood concentrations and prior information. In the past decade, many studies have developed optimal sampling strategies to estimate pharmacokinetic parameters as accurately as possible using either multiple regression analysis or MAPB estimation. This has been done for many drugs, especially immunosuppressants and anticancer agents. Methods of development for optimal sampling strategies (OSS) are diverse and heterogeneous. This review provides a comprehensive overview of OSS development methodology using MAPB pharmacokinetic parameter estimation, determines the transferability of published OSSs, and compares sampling strategies determined by MAPB estimation and multiple regression analysis. OSS development has the following components: 1) prior distributions; 2) reference value determination; 3) optimal sampling time identification; and 4) validation of the OSS. Published OSSs often lack all data necessary for the OSS to be clinically transferable. MAPB estimation is similar to multiple regression analysis in terms of predictive performance but superior in flexibility.
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13
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Martin ST, Tichy EM, Gabardi S. Belatacept: A Novel Biologic for Maintenance Immunosuppression After Renal Transplantation. Pharmacotherapy 2011; 31:394-407. [DOI: 10.1592/phco.31.4.394] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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14
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Hon YY, Chamberlain CE, Kleiner DE, Ring MS, Hale DA, Kirk AD, Mannon RB. Evaluation of tacrolimus abbreviated area-under-the-curve monitoring in renal transplant patients who are potentially at risk for adverse events. Clin Transplant 2011; 24:557-63. [PMID: 19925470 DOI: 10.1111/j.1399-0012.2009.01143.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
In a cohort of 32 renal transplant patients who are potentially at risk for adverse events, we compared tacrolimus (TAC) abbreviated AUC values calculated by a method developed in Asians (AUCw) with those derived for Caucasians (AUCa). The relationships between TAC trough (C0), abbreviated AUC, and biopsy results were also assessed. Forty-eight AUCs and 15 associated biopsies were evaluated. For AUCs obtained only from Caucasian patients, median AUCw value was lower than that of AUCa (104 vs. 115 ng×h/mL, n=29, p<0.0001). AUCs obtained from the two methods for all patients correlated with C0 (rs>0.72, n=48, p<0.0001). Median AUCw (72.9 vs. 174 ng×h/mL, p=0.043) and AUCa (81.0 vs. 203 ng×h/mL, p=0.043) were lower in patients experiencing biopsy-proven acute rejection (AR) than those with normal histology. C0 tended to be lower in biopsies showing AR>6 months post-transplant (5.80 vs. 11.0 ng/mL, p=0.110). Thus, lower abbreviated AUCs were obtained for Caucasians using a method developed in Asians. C0 correlated well with abbreviated AUCs. Lower C0 and AUC appeared to be associated with biopsy-proven AR>6 months post-transplant. Further prospective evaluation of TAC AUC and C0 monitoring in a larger cohort of patients is warranted.
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Affiliation(s)
- Yuen Yi Hon
- Pharmacy Department, Clinical Center, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA.
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15
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Ji M, Kim S, Chung HJ, Lee W, Chun S, Min WK. Evaluation of the MassTrak Immunosuppressant XE Kit for the determination of everolimus and cyclosporin A in human whole blood employing isotopically labeled internal standards. ACTA ACUST UNITED AC 2011; 49:2021-7. [DOI: 10.1515/cclm.2011.669] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
AbstractLiquid chromatography-tandem mass spectrometry (LC-MS/MS) is widely used for therapeutic drug monitoring of immunosuppressants given to transplant recipients. This study evaluated the performance of the newly introduced MassTrak Immunosuppressant XE Kit (Waters Corporation; “the Kit”) in the determination of everolimus and cyclosporin A (CsA) using LC-MS/MS.The linearity, precision, detection limit, carryover and matrix effect of the Kit and comparison of the in-house method and Kit procedure were evaluated according to Clinical and Laboratory Standards Institute guidelines.The Kit afforded good linearity in the measurement of everolimus from 2 to 26 ng/mL (RThe Kit employing isotopically labeled internal standards provides reliable measurements of immunosuppressant levels over a broad range of concentrations.
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Brandt C, Liman P, Bendfeldt H, Mueller K, Reinke P, Radbruch A, Worm M, Baumgrass R. Whole blood flow cytometric measurement of NFATc1 and IL-2 expression to analyze cyclosporine A-mediated effects in T cells. Cytometry A 2010; 77:607-13. [PMID: 20583270 DOI: 10.1002/cyto.a.20928] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
The calcineurin inhibitor Cyclosporine A (CsA) is one of the crucial immunosuppressive drugs given after organ transplantation. The small therapeutic window of CsA generates the dilemma that efficient and toxic drug doses differ only slightly. Moreover, these threshold concentrations differ considerably between individuals; therefore, functional assays are urgently needed. We explored whether the transcription factor NFATc1, a direct as well as indirect target of CsA, can be used as a potential biomarker to determine the individual immunosuppressive activity of CsA. First, in isolated human T cells we showed that flow cytometry is practicable to measure NFATc1, the most abundant NFATc isoform in activated T cells. Second, for whole blood we developed a flow cytometric assay to determine in parallel the inducible transcription factor NFATc1 and the cytokine IL-2 in stimulated T cells. We found that added CsA inhibits both the expression of NFATc1 and IL-2 in T cells of stimulated whole blood samples with IC(50) values of 200 and 150 nM, respectively. The intra- and inter-assay variability was low, and clinical practicability was good. Further experiments have to demonstrate whether the parallel cytometric measurement of NFATc1 and IL-2 in whole blood is a good predictor of individual CsA efficacy and toxicity in CsA-treated patients.
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Affiliation(s)
- Claudia Brandt
- Deutsches Rheuma-Forschungszentrum (DRFZ), Berlin, Germany
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Abstract
Cyclosporine A and tacrolimus (Tac) are inmunosuppresive drugs with a narrow therapeutic range. Underdosing is associated with organ rejection, whereas overdosing could result in toxicity. Therapeutic drug monitoring at different postdose times is necessary to maintain the blood concentrations within a target window. These calcineurin inhibitors are characterized by a broad interindividual pharmacokinetics variability, which makes the determination of the initial dose difficult. In a patient receiving a dose, the amount of the drug that is measured in the blood determines its bioavailability, which depends on the absorption, biotransformation, and elimination of the drug. These processes are primarily controlled by efflux pumps and enzymes of the cytochrome P (CYP) 450 family. DNA variants at the genes encoding these proteins contribute to the interindividual heterogeneity for calcineurin inhibitors metabolism. Cyclosporine A and Tac are metabolized by CYP3A4 and CYP3A5, and several single nucleotide polymorphisms in the two genes have been associated with differences in drug clearance. Carriers of the CYP3A5 wild-type allele have a higher CYP3A5 expression compared with individuals who are homozygous for a common DNA variant that affects gene splicing (CYP3A5*3). For renal transplant recipients receiving Tac, homozygotes for this nonexpression allele would exhibit significantly lower Tac clearance and may require a lower dose to remain within the blood target concentration compared with CYP3A5 expressors. To date, this CYP3A5 variant is the only reported genetic factor to predict the appropiate starting dosage of Tac, avoiding overdosing and improving the outcome of renal transplantation.
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Felipe CR, Park SI, Pinheiro-Machado PG, Garcia R, Casarini DE, Moreira S, Tedesco-Silva Jr H, Medina-Pestana JO. Cyclosporine and sirolimus pharmacokinetics and drug-to-drug interactions in kidney transplant recipients. Fundam Clin Pharmacol 2009; 23:625-31. [DOI: 10.1111/j.1472-8206.2009.00699.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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Balda S, Inza A, Odriozola N, Zárraga S, García-Erauskin G, Lampreabe I. Combination of everolimus and tacrolimus in kidney transplant patients with intolerance to mycophenolate mofetil/mycophenolic acid. Transplant Proc 2009; 41:2095-8. [PMID: 19715841 DOI: 10.1016/j.transproceed.2009.06.061] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
OBJECTIVE Most immunosuppressive protocols in de novo renal transplantation include tacrolimus in combination with mycophenolate mofetil/mycophenolic acid (MMF/MPA) and prednisone. A variable percentage of patients show intolerance to MMF/MPA needing a reduction, interruption, or suspension of the drug, thereby exposing the patient to a greater risk of a rejection episode. The association of everolimus and tacrolimus may prove to be an alternative option in such cases. The aim of this study was to present our clinical experience, evaluating the incidence of graft rejection. PATIENTS AND METHODS We performed a descriptive study of 19 kidney transplant patients from 2001-2008 who were treated with tacrolimus, MMF/MPA, and prednisone and displayed gastrointestinal or hematological adverse events to MMF/MPA, which were addressed with everolimus. We analyzed parameters up to 2 years after the change. RESULTS The doses and levels of everolimus were increased progressively. At the same time, we decreased the doses and levels of tacrolimus. Renal function remained stable during the period and there was no case of a rejection episode during the 2 years. Only 5 patients (26%) showed side effects which were attributable to everolimus; 36% of patients required starting and/or increasing the erythropoietin dose, 15% required iron supplements, 15% required diuretics, and 31% began or increased treatment with statins. CONCLUSION Our experience suggested that a combination of tacrolimus and everolimus may be a safe, effective alternative for kidney transplant patients who show intolerance to MMF/MPA.
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Affiliation(s)
- S Balda
- Department of Nephrology, Hospital San Pedro, Logroño, La Rioja, Spain.
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20
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Recent development in application of high performance liquid chromatography-tandem mass spectrometry in therapeutic drug monitoring of immunosuppressants. J Immunol Methods 2008; 336:98-103. [DOI: 10.1016/j.jim.2008.05.001] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2007] [Revised: 04/28/2008] [Accepted: 05/01/2008] [Indexed: 11/22/2022]
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21
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Ekbal NJ, Holt DW, MacPhee IAM. Pharmacogenetics of immunosuppressive drugs: prospect of individual therapy for transplant patients. Pharmacogenomics 2008; 9:585-96. [DOI: 10.2217/14622416.9.5.585] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The immunosuppressive drugs used in solid-organ transplantation are potent and toxic agents with narrow therapeutic ranges. Underdosing is associated with immunological rejection of the transplanted organ, whereas overdosing results in infections, malignancy and direct toxicity to a number of organs. Pharmacokinetic heterogeneity makes initial dose determination difficult, as there is a poor correlation between dose and blood concentration. Therapeutic drug monitoring is available but the pharmacokinetic–pharmacodynamic association is imperfect and it does not help in achieving target blood concentrations during the critical early 2–3 days after transplantation. Genetic polymorphisms in drug targets, drug-metabolizing enzymes and drug efflux pumps have been identified as potential targets for developing a pharmacogenetic strategy to individualize initial drug choice and dose. To date, use of the CYP3A5 genotype to predict the appropriate initial dose of tacrolimus is the most promising option for individualization of drug therapy in organ transplantation.
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Affiliation(s)
- Nasirul J Ekbal
- St George’s, University of London, Cellular and Molecular Medicine: Renal Medicine, Cranmer Terrace, London, SW17 0RE, UK
| | - David W Holt
- St George’s, University of London, Cardiac and Vascular Sciences: Analytical Unit, Cranmer Terrace, London, SW17 0RE, UK
| | - Iain AM MacPhee
- St George’s, University of London, Cellular and Molecular Medicine: Renal Medicine, Cranmer Terrace, London, SW17 0RE, UK
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van Rossum HH, Romijn FPHTM, Sellar KJ, Smit NPM, van der Boog PJM, de Fijter JW, van Pelt J. Variation in Leukocyte Subset Concentrations Affects Calcineurin Activity Measurement: Implications for Pharmacodynamic Monitoring Strategies. Clin Chem 2008; 54:517-24. [DOI: 10.1373/clinchem.2007.097253] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
AbstractBackground: In renal transplantation patients, therapeutic drug monitoring of the calcineurin (CN) inhibitor cyclosporin A (CsA) is mandatory because of the drug’s narrow therapeutic index. Pharmacodynamic monitoring of CN inhibition therapy could provide a tool to define and maintain the therapeutic efficacy of CsA therapy. We investigated the effect of variation in cell counts of leukocyte subsets on leukocyte CN activity measurement in renal transplant recipients.Methods: We measured leukocyte CN activity, whole blood CsA concentrations, and leukocyte subset cell counts in 25 renal transplant recipients. Blood was collected before graft implantation and CsA therapy, 1 day before transplantation when CsA therapy was already started, and 5 days after transplantation. Monocyte, granulocyte, CD4+ T-cell, CD8+ T-cell, B-cell, and natural killer–cell CN activities and CsA inhibition sensitivities were determined in vitro by a spectrophotometric CN assay.Results: Leukocyte CN activity was inhibited after drug intake. Inter- and intrapatient variation in leukocyte subset cell counts resulted in variation of sample composition. The mean (SD) CN activity varied among leukocyte cell subsets, ranging from 650 (230) to 166 (26) pmol/min/106 cells for monocytes and CD4+ T cells, respectively. CsA half maximal inhibitory concentration (IC50) values ranged from 15 to 78 μg/L for monocytes and B cells, respectively.Conclusion: Inter- and intraindividual leukocyte subset cell count variation can affect measured CN activity independent of CsA concentration. Cell-specific activity and drug sensitivity should be considered for sample validation to optimize method specificity when pharmacodynamic monitoring strategies are applied in a clinical setting.
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Affiliation(s)
| | | | | | | | | | - Johan W de Fijter
- Nephrology, Leiden University Medical Center, Leiden, the Netherlands
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Teicher E, Vincent I, Bonhomme-Faivre L, Abbara C, Barrail A, Boissonnas A, Duclos-Vallée JC, Taburet AM, Samuel D, Vittecoq D. Effect of highly active antiretroviral therapy on tacrolimus pharmacokinetics in hepatitis C virus and HIV co-infected liver transplant recipients in the ANRS HC-08 study. Clin Pharmacokinet 2008; 46:941-52. [PMID: 17922559 DOI: 10.2165/00003088-200746110-00002] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
OBJECTIVE To characterise the interactions between tacrolimus and antiretroviral drug combinations in hepatitis C virus-HIV co-infected patients who had received a liver transplant. DESIGN An observational, open-label, multiple-dose, two-period, one-sequence design clinical trial in which patients received tacrolimus as an immunosuppressive therapy during the postoperative period and then had an antiretroviral drug regimen added. Tacrolimus pharmacokinetics were evaluated at steady state during these two periods. METHODS Fourteen patients participated in the study and seven participated in the intensified pharmacokinetic protocol. Patients were included if they had undergone liver transplantation for end-stage chronic hepatitis C, absence of opportunistic infection, a CD4 cell count of >150 cells/microL and an undetectable HIV plasma viral load (<50 copies/mL) under highly active antiretroviral therapy. During the posttransplantation period, the tacrolimus dose was adjusted according to blood concentrations. When liver function and the tacrolimus dose were stable, antiretroviral therapy was reintroduced. RESULTS When lopinavir/ritonavir were added to the tacrolimus regimen (seven patients), the tacrolimus dose was reduced by 99% to maintain the tacrolimus concentration within the therapeutic range. Only two patients were treated with nelfinavir, which led to a wide variation in inhibition of tacrolimus metabolism. When efavirenz (four patients) or a nucleoside analogue combination (one patient) was added, very little change in tacrolimus dosing was required. CONCLUSION The lopinavir/ritonavir combination markedly inhibited tacrolimus metabolism, whereas the effect of efavirenz was small. Tacrolimus dosing must be optimised according to therapeutic drug monitoring and the antiretroviral drug combination.
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Affiliation(s)
- Elina Teicher
- Internal Medicine and Infectious Diseases Department, Hôpital Paul Brousse, Assistance Publique Hôpitaux de Paris (AP-HP), Paris, France
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Crossreactivity of Isolated Everolimus Metabolites With the Innofluor Certican Immunoassay for Therapeutic Drug Monitoring of Everolimus. Ther Drug Monit 2007; 29:743-9. [DOI: 10.1097/ftd.0b013e31815b3cbf] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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25
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Ng FL, Holt DW, MacPhee IAM. Pharmacogenetics as a tool for optimising drug therapy in solid-organ transplantation. Expert Opin Pharmacother 2007; 8:2045-58. [PMID: 17714059 DOI: 10.1517/14656566.8.13.2045] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Existing immunosuppressive therapies used for solid-organ transplantation have narrow therapeutic indices, whereby underdosing is associated with acute immunological rejection of the transplanted organ and overdosing is associated with infections and malignancy, as well as organ-specific toxicities. There is significant inter-individual variation in the pharmacokinetics and pharmacodynamics of these drugs, an issue that has been addressed, in part, by therapeutic drug monitoring. Genetic polymorphisms in drug metabolising enzymes, drug efflux pumps and drug targets which may underly this heterogeneity have been identified and may provide a tool to guide prescribing. There are a number of associations between genotype and pharmacology, but as of now, only thiopurine-S-methyltransferase and cytochrome P450 3A5 have a sufficiently large influence to have potential in guiding therapy. Recent studies have also identified that donor genotype may play a significant role in immunosuppressive drug pharmacokinetics and pharmacodynamics.
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Affiliation(s)
- Fu Liang Ng
- Cellular and Molecular Medicine: Renal Medicine and Cardiac and Vascular Sciences Analytical Unit, St. George's, University of London, Cranmer Terrace, London, UK
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Howard AD. Long-term posttransplantation care: the expanding role of community nephrologists. Am J Kidney Dis 2006; 47:S111-24. [PMID: 16567237 DOI: 10.1053/j.ajkd.2005.12.040] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2005] [Accepted: 12/14/2005] [Indexed: 11/11/2022]
Abstract
Improvements in transplantation practices, immunosuppressive agents, and management of comorbid conditions have led to better outcomes for kidney transplant recipients. Transplantation has become the treatment of choice for patients with end-stage renal disease (ESRD). This has resulted in continued growth in the number of patients living with a functioning kidney allograft as a percentage of the total ESRD population. These patients require long-term follow-up care, which already is straining the limited resources of transplant centers. Community nephrologists are the logical choice to assume responsibility for the posttransplantation care of these patients after discharge from transplant centers when they are stabilized. Optimal management of kidney transplant recipients depends on regular interactive communication between the patient's community nephrologist and the transplant center. Open communication will not only facilitate the initial transition of care, it also will decrease the frequency of referrals back to the transplant center. In an ideal situation, the transplant center and community nephrologist would develop and discuss plans for discharge and transition of care for the individual patient before the actual kidney transplantation. Important issues for effective communication include changes in laboratory results and kidney function; pretransplantation and posttransplantation comorbid conditions, surgical complications, or adverse effects of medications; modifications to immunosuppressive therapy or other medications; recurrent hospitalizations or emergency care; and changes in biopsy results.
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Affiliation(s)
- Andrew D Howard
- Metropolitan Nephrology Associates, Alexandria, VA 22306, USA.
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Baldelli S, Zenoni S, Merlini S, Perico N, Cattaneo D. Simultaneous determination of everolimus and cyclosporine concentrations by HPLC with ultraviolet detection. Clin Chim Acta 2006; 364:354-8. [PMID: 16153624 DOI: 10.1016/j.cca.2005.07.019] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2005] [Revised: 07/29/2005] [Accepted: 07/29/2005] [Indexed: 11/17/2022]
Abstract
In the clinical practice of organ transplantation everolimus (RAD) is used in combination with cyclosporine (CsA), the most common antirejection agent. Both drugs show a narrow therapeutic window, which requires strict monitoring of their blood concentration. Simple methods for simultaneous measurement of RAD and CsA concentration are needed. As we have recently developed an HPLC-UV assay for RAD determination, we decided to implement it to allow concomitant measurement of CsA. The within- and between-day coefficients of variation of the measurement were less than 12.1% for RAD and 9.8% for CsA. The within- and between-day inaccuracy of quality control samples were less than 9.7% for RAD and less than 4.9% for CsA. The method was found accurate and precise and useful for simultaneous therapeutic monitoring of the two drugs.
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Affiliation(s)
- Sara Baldelli
- Department of Medicine and Transplantation, Ospedali Riuniti di Bergamo -, Mario Negri Institute for Pharmacological Research Via Gavazzeni, 11 - 24125, Bergamo, Italy
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28
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MacPhee IAM, Fredericks S, Holt DW. Does pharmacogenetics have the potential to allow the individualisation of immunosuppressive drug dosing in organ transplantation? Expert Opin Pharmacother 2005; 6:2593-605. [PMID: 16316299 DOI: 10.1517/14656566.6.15.2593] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
The immunosuppressive drugs used in organ transplantation have a narrow therapeutic index, with rejection occurring as a consequence of underdosing and infection, malignancy and a number of drug-specific side effects with excessive dosing. Significant heterogeneity in the dose of drug required to achieve therapeutic blood concentrations adds to the complexity of the problem, which has been partly resolved by therapeutic drug monitoring. Single nucleotide polymorphisms have been identified in genes encoding metabolic enzymes, drug efflux pumps and drug targets for most of the drugs in widespread use. A pharmacogenetic approach to immunosuppressive drug prescribing remains to be tested. Based on current evidence, the most promising strategy would be use of the cytochrome P450 3A5 expressor genotype to guide initial dosing with tacrolimus.
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Affiliation(s)
- Iain A M MacPhee
- Cellular and Molecular Medicine, Renal Medicine, St. George's Hospital, University of London, Cranmer Terrace, London, SW17 0RE, UK.
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29
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Wang S, Magill JE, Vicente FB. A fast and simple high-performance liquid chromatography/mass spectrometry method for simultaneous measurement of whole blood tacrolimus and sirolimus. Arch Pathol Lab Med 2005; 129:661-5. [PMID: 15859639 DOI: 10.5858/2005-129-0661-afashl] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
CONTEXT Combined immunosuppressant therapy using tacrolimus and sirolimus has demonstrable benefits. Simultaneous chromatographic monitoring of whole blood tacrolimus and sirolimus is useful for reducing reagent consumption and turnaround time. We report here a simple and rapid method using high-performance liquid chromatography/mass spectrometry for simultaneous measurement of whole blood tacrolimus and sirolimus. OBJECTIVE To develop and validate a high-performance liquid chromatography/mass spectrometry method that is suitable for clinical laboratories and that is simple, rapid, and cost-effective. DESIGN Whole blood (80 microL) was mixed with zinc sulfate solution, followed by protein precipitation with acetonitrile containing the internal standards. After brief centrifugation, the supernatant (20 microL) was injected onto a C18 guard column. The drug and the internal standard ammonium adducts were monitored by multiple reaction monitoring. One-point calibration at levels of 200 ng/mL (249 nM) tacrolimus and 100 ng/mL (109 nM) sirolimus was prepared by adding tacrolimus and sirolimus to immunosuppressant-free whole blood. RESULTS The assay took 2.5 minutes per sample injection. The total imprecision was between 2.46% and 7.04% for tacrolimus and between 5.22% and 8.30% for sirolimus across the concentrations tested. No carryover was observed, and recoveries were 92% to 98% for tacrolimus and 100% for sirolimus at all levels tested. The tacrolimus was linear from 0.52 to 155.5 ng/mL (0.65-193.4 nM), and sirolimus was linear from 0.47 to 94.8 ng/mL (0.51-103.7 nM). Biases of correlations with commercial methods were within 7%. CONCLUSIONS This improved method is simple, fast, cost-effective, and suitable for clinical laboratories. It has been implemented for routine clinical monitoring of posttransplantation immunosuppressant therapy.
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Affiliation(s)
- Sihe Wang
- Department of Pathology and Laboratory Medicine, The Feinberg School of Medicine, Northwestern University, Chicago, Ill, USA.
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30
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Immunosuppressants: Pharmacokinetics, methods of monitoring and role of high performance liquid chromatography/mass spectrometry. ACTA ACUST UNITED AC 2005. [DOI: 10.1016/j.cair.2005.12.001] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Cattaneo D, Tankiewicz A, Merlini S, Perico N, Remuzzi G. Pharmacogenetics and pharmacogenomics of immunosuppressive agents: perspective for individualized therapy. Per Med 2004; 1:53-62. [DOI: 10.1517/17410541.1.1.53] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Immunosuppressive therapy has markedly improved over the past years with the advent of highly potent and rationally targeted immunosuppressive agents. Since these drugs are characterized by a narrow therapeutic index, major efforts have been carried out to define therapeutic windows based on the blood levels of each immunosuppressant, and relating those concentrations to clinical events. Although pharmacokinetic-based approaches are currently used as useful tools to guide drug dosing, they present several limitations. Pharmacogenomics – a science that studies the inherited basis of differences between individual responses to drugs in order to identify the best dose and therapy for each patient – might represent a complementary support. Preliminary studies that have focused on polymorphisms of genes encoding enzymes involved in drug metabolism, drug distribution, and pharmacological target, have shown promising results. Indeed, pharmacogenomics holds promise for improvement in the ability to individualize pharmacological therapy based on the patient’s genetic profile.
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Affiliation(s)
- Dario Cattaneo
- Mario Negri Institute, Department of Medicine and Transplantation Ospedali Riuniti di Bergamo, Mario Negri Institute for Pharmacological Research, Via Gavazzeni 11- 24125 Bergamo, Italy.
| | - Anna Tankiewicz
- Medical University of Bialystok, Department of Pharmacodynamics, Medical University of Bialystok, Poland
| | - Simona Merlini
- Mario Negri Institute, Department of Medicine and Transplantation Ospedali Riuniti di Bergamo, Mario Negri Institute for Pharmacological Research, Via Gavazzeni 11- 24125 Bergamo, Italy
| | - Norberto Perico
- Mario Negri Institute, Department of Medicine and Transplantation Ospedali Riuniti di Bergamo, Mario Negri Institute for Pharmacological Research, Via Gavazzeni 11- 24125 Bergamo, Italy
| | - Giuseppe Remuzzi
- Mario Negri Institute, Department of Medicine and Transplantation Ospedali Riuniti di Bergamo, Mario Negri Institute for Pharmacological Research, Via Gavazzeni 11- 24125 Bergamo, Italy
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Cattaneo D, Merlini S, Pellegrino M, Carrara F, Zenoni S, Murgia S, Baldelli S, Gaspari F, Remuzzi G, Perico N. Therapeutic drug monitoring of sirolimus: effect of concomitant immunosuppressive therapy and optimization of drug dosing. Am J Transplant 2004; 4:1345-51. [PMID: 15268738 DOI: 10.1111/j.1600-6143.2004.00517.x] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Sirolimus (SRL) is a new immunosuppressant which shares a common metabolic pathway with several other immunosuppressive agents. This leads to potential pharmacokinetic interactions that might affect SRL blood levels with relevant clinical consequences. As a validated laboratory, 2658 SRL trough samples (corresponding to 495 kidney transplant recipients treated with different immunosuppressive regimens) from more than 40 Italian Transplant Units were analyzed. We found that dose-normalized SRL trough levels were significantly higher in patients treated with cyclosporine (CsA) and SRL (4.15 +/- 2.23 ng/mL/mg SRL), compared with patients treated with mycophenolate mofetil (MMF) and SRL (3.26 +/- 1.86 ng/mL/mg SRL; p < 0.01) or with MMF, steroids and SRL (2.52 +/- 1.73 ng/mL/mg SRL; p < 0.01). Mean intra- and interpatient variabilities were 19% and 47%, respectively. Both parameters are significantly affected by the time postsurgery, with the first week post transplantation being associated with the greatest variability. As additional analysis, a simple dose-adjustment formula has been proposed as a useful tool to guide SRL dose changes. The proposed equation has been able to predict SRL concentration after a dose change in 73% of the tested samples. These findings suggest that different immunosuppressants significantly interfere with SRL bioavailability. Strategies aimed at reducing variability in SRL exposure may have a positive clinical impact.
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Affiliation(s)
- Dario Cattaneo
- Department of Medicine and Transplantation, Ospedali Riuniti di Bergamo - Mario Negri Institute for Pharmacological Research, Bergamo, Italy.
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Affiliation(s)
- David W Holt
- Analytical Unit, St. Georges Hospital Medical School, London, England.
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Taylor PJ. Therapeutic Drug Monitoring of Immunosuppressant Drugs by High-Performance Liquid Chromatography–Mass Spectrometry. Ther Drug Monit 2004; 26:215-9. [PMID: 15228168 DOI: 10.1097/00007691-200404000-00023] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The currently expanding range of immunosuppressant agents has placed new challenges on therapeutic drug-monitoring (TDM) services. Many of these drugs require the measurement of concentrations with subsequent dosage adjustment to maximize efficacy while minimizing toxicity. HPLC-mass spectrometry (HPLC-MS) is a relatively new technique for drug quantification and thus TDM of immunosuppressant drugs. Although mass spectrometry relies on producing, differentiating, and detecting ions in the gas phase, the development of the atmospheric pressure ionization interface (electrospray and chemical ionization) has enabled the direct coupling of solution introduction of compounds, via HPLC, to the mass analyzer. The impetus for using HPLC-MS for immunosuppressant measurement has come from the highly potent low-dose immunosuppressant drugs tacrolimus and sirolimus, which have low nanogram per milliliter circulating concentrations. A number of strategies have been reported for sample preparation and ways to automate these processes with solid-phase extraction and 2-dimensional chromatography. The disadvantages of HPLC-MS are initial cost of equipment and availability of suitably skilled scientific staff. The advantages of HPLC-mass spectrometry are high sensitivity, specificity, small sample requirements, minimal sample preparation, rapid throughput, and simultaneous measurement. Further, scientists have the ability to develop methods to measure new immunosuppressant drugs by HPLC-MS before commercial assays become available. With potential applications increasing in immunosuppressive drug monitoring, it can be envisaged that HPLC-MS may become standard equipment in TDM laboratories of the future.
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Affiliation(s)
- Paul J Taylor
- Department of Medicine, The University of Queensland, and Department of Clinical Pharmacology and Australian Bioanalytical Services Pty Ltd, Princess Alexandra Hospital, Brisbane, QLD 4102, Australia.
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35
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Cattaneo D, Perico N, Remuzzi G. From pharmacokinetics to pharmacogenomics: a new approach to tailor immunosuppressive therapy. Am J Transplant 2004; 4:299-310. [PMID: 14961981 DOI: 10.1111/j.1600-6143.2004.00312.x] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
One of the main tasks in the management of organ transplantation is the optimization of immunosuppressive therapy, in order to provide therapeutic efficacy limiting drug-related toxicity. In the past years major efforts have been carried out to define therapeutic windows based on blood/plasma levels of each immunosuppressant relating those concentrations to drug dosing and clinical events. Although this traditional approach is able to identify environmental and nongenetic factors that can influence drug exposure during the course of treatment, it presents limitations. Therefore, complementary strategies are advocated. The advent of the genomic era gives birth to pharmacogenomics, a science that studies how the genome as a whole, including single genes as well as gene-to-gene interactions, may affect the action of a drug. This science is of particular importance for drugs characterized by a narrow therapeutic index, such as the immunosuppressants. Preliminary studies focused on polymorphisms of genes encoding for enzymes actively involved in drug metabolism, drug transport and pharmacological target. Pharmacogenomics holds promise for improvement in the ability to individualize immunosuppressive therapy based on the patient's genetic profile, and can be viewed as a support to traditional therapeutic drug monitoring. However, the clinical applicability of this approach is still to be proven.
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Affiliation(s)
- Dario Cattaneo
- Department of Medicine and Transplantation, Ospedali Riuniti di Bergamo-Mario Negri Institute for Pharmacological Research, Bergamo, Italy.
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Fredericks S, Holt DW, MacPhee IAM. The pharmacogenetics of immunosuppression for organ transplantation: a route to individualization of drug administration. ACTA ACUST UNITED AC 2004; 3:291-301. [PMID: 14575518 DOI: 10.2165/00129785-200303050-00001] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Transplantation has transformed the treatment of patients with organ failure in a number of clinical settings, and immunosuppressive drug therapy is fundamental to its success. However, all the drugs in current use have a narrow therapeutic index. Under-dosing can lead to rejection, while over-dosing increases the risks of infection, malignant disease, and serious drug-specific adverse effects, including diabetes mellitus, nephrotoxicity, hypertension, and hyperlipidemia. Heterogeneity in the pharmacokinetics of these drugs makes initial dose determination difficult, as there is a poor correlation between dose and blood concentration. This results in difficulties in achieving target blood concentrations early after transplantation, which are important for reducing the rate of immunological rejection. This problem is compounded by the observation that neither drug dose nor drug blood concentration accurately predict clinical efficacy or toxicity. The main determinant of heterogeneity in dose requirements is intestinal absorption of the active drug. The oxidative enzymes, cytochrome P450 (CYP) 3A4 and CYP3A5, and the drug efflux pump P-glycoprotein (P-gp) in enterocytes regulate this process. Most substrates for the P-gp pump are also substrates for the CYP3A enzymes. An efficient barrier to xenobiotic absorption is formed by the CYP enzymes and P-gp, and by the two systems working synergistically. Genetic polymorphisms have been reported for the genes associated with the expression of the CYP3A enzymes and P-gp. Genotyping patients for CYP3A genes has the potential to aid the establishment of optimal dosage regimens for transplant patients. Genetic polymorphism of the multiple drug resistance gene-1 (MDR1, also known as ABCB1) [3435C/T] and the CYP3A5 genes (CYP3A5*1, CYP3AP1*1) have the greatest potential to influence the pharmacokinetics of immunosuppressants. Homozygosity of the T allele of the MDR1 3435C/T polymorphism has been associated with reduced enterocyte expression of P-gp resulting in increased drug absorption. The presence of the CYP3A5*1 allele is necessary for the production of a fully catalytic CYP3A5 protein, and also influences the ratio of CYP3A4 : CYP3A5 as well as the overall CYP3A catalytic activity. The CYP3A4 : CYP3A5 ratio may, in turn, influence the pattern of drug metabolites formed. Heterogeneity in the production of active and inactive metabolites has implications for both the pharmacokinetics and pharmacodynamics of these drugs.Gene frequencies and drug dose requirements differ between ethnic groups. Ethnic differences in dose requirements for immunosuppressants have been discussed widely. However, ethnicity is a rather crude marker for genotype. Pharmacogenetic typing offers the possibility of significant improvement in the individualization of immunosuppressive drug prescribing with reduced rates of rejection and toxicity.
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Affiliation(s)
- Salim Fredericks
- Department of Cardiovascular Medicine, Analytical Unit, St George's Hospital Medical School, Cranmer Terrace, London SW17 0RE, UK
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Holt CD, Ingle G, Sievers TM. Inhibitors of Calcineurin. J Pharm Pract 2003. [DOI: 10.1177/0897190003260317] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Before the early 1980s, patient and allograft survival for solid organ transplant recipients was dismal. By 1983, the first calcineurin blocker, cyclosporine (Sandimmun), had been introduced, and outcomes were dramatically improved. However, cyclosporine macroemulsion had suboptimal pharmacokinetics, significant drug interactions, and several adverse effects, including nephrotoxicity, neurotoxicity, hyperlipidemia, and hypertension. Recent advances with cyclosporine include the introduction of modified dosage formulations: Neoral, a microemulsion, and several generic microemulsion products. The potent second-generation calcineurin blocker tacrolimus (Prograf) was introduced in 1994 and has become the drug of choice for several types of transplant recipients. Although tacrolimus has improved pharmacokinetics and therapeutic drugmonitoring parameters, it has adverse effects such as nephrotoxicity, neurotoxicity, and diabetes. Thus, current immunosuppressive regimens implementing calcineurin blockers often involve additional immunosuppressive agents to “spare” the use of these agents, minimizing their adverse effects. This article reviews the mechanisms of action, pharmacokinetics, clinical use, therapeutic drug monitoring, drug interactions, adverse effects, and dosing of cyclosporine and tacrolimus in solid organ transplant recipients.
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Affiliation(s)
- Curtis D. Holt
- 10833 Le Conte Ave, Room 77-120 CHS, Division of Liver and Pancreas Transplantation, Department of Surgery, UCLA Medical Center, Los Angeles, CA 90095-7054
| | - Gordon Ingle
- BCPS, Dumont-UCLA Transplant Center, Los Angeles, California
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Di Marco GS, de Andrade MCC, Felipe CR, Alfieri F, Gooding A, Silva HT, Pestana JODA, Casarini DE. Determination of Sirolimus Blood Concentration Using High-Performance Liquid Chromatography with Ultraviolet Detection. Ther Drug Monit 2003; 25:558-64. [PMID: 14508378 DOI: 10.1097/00007691-200310000-00004] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Different HPLC methods have been developed and used to determined sirolimus blood concentrations. These methods show different performance characteristics, mostly related to peak interference, recovery, assay sensitivity, and turnaround times. OBJECTIVE We adapted, improved, and validated an HPLC method with UV detection for measurement of sirolimus in whole blood clinical samples. METHODS The standards, quality controls, or patient samples (0.25 or 0.5 mL) and internal standard (desmethoxysirolimus) were extracted with 1-chlorobutane. After evaporation, the extract was reconstituted in a 70% acetonitrile/water mixture and analyzed onto a reverse-phase C18 column at 50 degrees C under a flow rate of 1.0 mL/min in the HPLC system. Ultraviolet detection was performed at 278 nm, with sensitivity setting of 0.010 AUFS. Identification of peaks of interest was by retention time; quantification of sirolimus was based on a peak area ratio. RESULTS Analytic recovery ranging from 96 to 120% (CV = 3.7 to 16.8%; bias = -4.2 to 16.7%) was observed throughout the assay's linear range (2.5-150.0 ng/mL). The lower limit of quantification for both sample volumes (0.25 or 0.5 mL) was 2.5 ng/mL (CV = 12 and 15%, bias = -1.2 and 4%, respectively). The intra- and interassay imprecision ranged from 6.2 to 14.4% and from 9.1 to 18.6%, with bias ranging from 1.3 to 12.9% and -1.8% to 7.1, for quality control levels of 3, 10, and 20 ng/mL. Whole blood and extracted samples are stable at room temperature and at 4 and -20 degrees C for 1 week and 3 days, respectively. Chromatograms showed good separation free of interfering peaks. A set of 45 samples can be extracted in 2 h, allowing results within 24 h. CONCLUSION This HPLC-UV method shows good and reproducible performance, satisfying all requirements of an assay designated to be applied in therapeutic drug monitoring strategies after organ transplantation.
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Affiliation(s)
- Giovana Seno Di Marco
- Department of Medicine, Nephrology Division, Federal University of São Paulo, Brazil
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