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Nishino T, Takahashi K, Tomori S, Ono S, Mimaki M. Cyclosporine A C 1.5 monitoring reflects the area under the curve in children with nephrotic syndrome: a single-center experience. Clin Exp Nephrol 2021; 26:154-161. [PMID: 34559341 DOI: 10.1007/s10157-021-02139-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2021] [Accepted: 09/18/2021] [Indexed: 11/25/2022]
Abstract
BACKGROUND The currently used single-monitoring method for drug-blood-level evaluation in cyclosporine A (CsA) treatment for nephrotic syndrome (NS) was established through hourly measurements based on adult organ transplantation. However, the pharmacokinetics may differ due to different concomitant medications, age, and conditions. This study was conducted to determine the measurement timing that best reflects the CsA area under the curve (AUC) in pediatric NS. METHODS This retrospective study included children aged 2-14 years who were started on CsA treatment for idiopathic NS during 2013-2020. AUC0-4 was calculated from 7 points, before and 0.5, 1, 1.5, 2, 3, and 4 h after administration. Mean values at each timing were compared with age-dependent different drug forms. Correlation between AUC0-4 and measurement timing was analyzed. RESULTS There were 13 patients (11 boys) whose median age during testing was 7.3 years, and the total number of measurements was 94. The highest timing of CsA concentrations was found in C1 59.6%. The content liquid used at younger ages had a faster absorption time to peak value and lower blood concentration than those of capsules. Among the significant correlations observed, AUC0-4 and C1.5 showed the strongest significant correlation coefficient (r = 0.93, P < 0.001). CONCLUSION In pediatric NS, CsA metabolism may be faster than that in previous organ transplantation. Compared with C2, C1.5 monitoring may result in better disease control as it can best reflect the AUC0-4 and peak values associated with side effects, which are indicators of therapeutic efficacy.
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Affiliation(s)
- Tomohiko Nishino
- Department of Pediatrics, Teikyo University School of Medicine, 2-11-1, Kaga, Itabashi-ku, Tokyo, 173-8605, Japan.
| | - Kazuhiro Takahashi
- Department of Pediatrics, Teikyo University School of Medicine, 2-11-1, Kaga, Itabashi-ku, Tokyo, 173-8605, Japan
| | - Shinya Tomori
- Department of Pediatrics, Teikyo University School of Medicine, 2-11-1, Kaga, Itabashi-ku, Tokyo, 173-8605, Japan
| | - Sayaka Ono
- Department of Pediatrics, Teikyo University School of Medicine, 2-11-1, Kaga, Itabashi-ku, Tokyo, 173-8605, Japan
| | - Masakazu Mimaki
- Department of Pediatrics, Teikyo University School of Medicine, 2-11-1, Kaga, Itabashi-ku, Tokyo, 173-8605, Japan
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Hamdan II, El-Sabawi D, Tverdokhleb NM, Lantushenko AO, Evstigneev MP, Abu-Dahab R. Studies on potential interaction between cinacalcet hydrochloride and diclofenac sodium. Biophys Chem 2020; 266:106460. [PMID: 32890944 DOI: 10.1016/j.bpc.2020.106460] [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: 06/03/2020] [Revised: 08/13/2020] [Accepted: 08/16/2020] [Indexed: 10/23/2022]
Abstract
Cinacalcet (CT) is an important drug for the treatment hyperparathyroidism. Only few studies havereported thepotential interaction between CT and other potentially coadministered drugs. In this study, the potential of invitro interaction between CT and DF sodium (DF-Na) was investigated. An ion pair salt of CT with DF was obtained by mixing the two compounds in solution; the product was fully characterized by HPLC analysis, UV, FTIR, NMR spectroscopy in addition to DSC. The solubility and partition coefficients were found to significantly decrease and increase, respectively, for the obtained ion pair salt in comparison to the parent compounds. Dissolution studies in phosphate buffer pH 6.8 revealed a significant decrease in the dissolution of an already poorly water soluble drug (decrease to ~20% of the original). Permeation studies, through Caco-2 cells monolayer, revealed a significant decrease in permeation of CT when coexisted with DF (almost to half). Apparent permeability coefficient (Papp) decreased from 3.6 × 10-6 to 1.8 × 10-6 cm/s. Interestingly, a structure for the formed CT-DF salt that could explain the above findings (increase in lipophilicity), could be proposed based on structural modelling, molecular dynamic simulations and NMR proton chemical shifts analysis.
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Affiliation(s)
- Imad I Hamdan
- School of Pharmacy, The University of Jordan, Amman 11942, Jordan.
| | - Dina El-Sabawi
- School of Pharmacy, The University of Jordan, Amman 11942, Jordan
| | - N M Tverdokhleb
- Laboratory of Molecular and Cell Biophysics, Sevastopol State University, Sevastopol 299053, Russian Federation
| | - A O Lantushenko
- Laboratory of Molecular and Cell Biophysics, Sevastopol State University, Sevastopol 299053, Russian Federation
| | - M P Evstigneev
- Laboratory of Molecular and Cell Biophysics, Sevastopol State University, Sevastopol 299053, Russian Federation
| | - Rana Abu-Dahab
- School of Pharmacy, The University of Jordan, Amman 11942, Jordan
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Schwarz P, Schwarz PV, Felske-Zech H, Dannaoui E. In vitro interactions between isavuconazole and tacrolimus, cyclosporin A or sirolimus against Mucorales. J Antimicrob Chemother 2020; 74:1921-1927. [PMID: 30934052 DOI: 10.1093/jac/dkz102] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2018] [Revised: 02/16/2019] [Accepted: 02/19/2019] [Indexed: 02/07/2023] Open
Abstract
OBJECTIVES To evaluate the in vitro interactions of isavuconazole with immune suppressors (tacrolimus, cyclosporin A or sirolimus) against 30 Mucorales isolates belonging to the most common species responsible for mucormycosis in humans (Rhizopus arrhizus, Rhizopus delemar, Rhizopus microsporus, Lichtheimia corymbifera, Lichtheimia ramosa, Mucor circinelloides and Rhizomucor pusillus). METHODS In vitro interaction was evaluated by a microdilution chequerboard technique. RESULTS Combination of isavuconazole with tacrolimus, cyclosporin A or sirolimus, was synergistic for 50%, 46% and 7% of the isolates, respectively. Antagonistic interaction was observed for 4% of the isolates for the combination with cyclosporin A (one R. arrhizus isolate) and for 32% of the isolates for the combination with sirolimus (six R. arrhizus isolates and three R. pusillus isolates). CONCLUSIONS These in vitro data show that calcineurin inhibitors are more likely than inhibitors of the mTOR pathway to enhance the activity of isavuconazole against Mucorales. These in vitro results warrant further animal experiments.
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Affiliation(s)
- Patrick Schwarz
- Department of Internal Medicine, Respiratory and Critical Care Medicine, University Hospital Marburg, Marburg, Germany.,Center for Invasive Mycoses and Antifungals, Philipps University Marburg, Marburg, Germany
| | - Petra V Schwarz
- Center for Invasive Mycoses and Antifungals, Philipps University Marburg, Marburg, Germany
| | - Heike Felske-Zech
- Department of Legal Medicine, University Hospital Gießen, Gießen, Germany
| | - Eric Dannaoui
- Université Paris Descartes, Faculté de Médecine, AP-HP, Hôpital Européen Georges Pompidou, Unité de Parasitologie-Mycologie, Paris, France.,Dynamyc Research Group (EA 7380), Paris Est Créteil University, Créteil, France
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In Vitro Interaction between Isavuconazole and Tacrolimus, Cyclosporin A, or Sirolimus against Aspergillus Species. J Fungi (Basel) 2020; 6:jof6030103. [PMID: 32650564 PMCID: PMC7560155 DOI: 10.3390/jof6030103] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2020] [Revised: 06/07/2020] [Accepted: 06/16/2020] [Indexed: 12/13/2022] Open
Abstract
The interaction of isavuconazole with immunosuppressors (tacrolimus, cyclosporin A, or sirolimus) against 30 Aspergillus isolates belonging to the most common species responsible for invasive aspergillosis in humans (Aspergillus flavus, Aspergillus fumigatus, Aspergillus nidulans, Aspergillus niger, and Aspergillus terreus) was evaluated in vitro by a microdilution checkerboard technique based on the EUCAST reference method for antifungal susceptibility testing. The interpretation of the results was performed based on the fractional inhibitory concentration index. The combination of isavuconazole with tacrolimus, cyclosporin A, or sirolimus, was synergistic for 56, 20, or 10% of the isolates, respectively. Interestingly synergy of the combination of isavuconazole with tacrolimus was also achieved for the majority of azole-resistant isolates of A. fumigatus, and for all A. niger isolates with isavuconazole minimal inhibitory concentrations ≥ 8 µg/mL. Antagonistic interactions were never observed for any combination tested.
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Vangala C, Pan J, Cotton RT, Ramanathan V. Mineral and Bone Disorders After Kidney Transplantation. Front Med (Lausanne) 2018; 5:211. [PMID: 30109232 PMCID: PMC6079303 DOI: 10.3389/fmed.2018.00211] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2018] [Accepted: 07/09/2018] [Indexed: 12/16/2022] Open
Abstract
The risk of mineral and bone disorders among patients with chronic kidney disease is substantially elevated, owing largely to alterations in calcium, phosphorus, vitamin D, parathyroid hormone, and fibroblast growth factor 23. The interwoven relationship among these minerals and hormones results in maladaptive responses that are differentially affected by the process of kidney transplantation. Interpretation of conventional labs, imaging, and other fracture risk assessment tools are not standardized in the post-transplant setting. Post-transplant bone disease is not uniformly improved and considerable variation exists in monitoring and treatment practices. A spectrum of abnormalities such as hypophosphatemia, hypercalcemia, hyperparathyroidism, osteomalacia, osteopenia, and osteoporosis are commonly encountered in the post-transplant period. Thus, reducing fracture risk and other bone-related complications requires recognition of these abnormalities along with the risk incurred by concomitant immunosuppression use. As kidney transplant recipients continue to age, the drivers of bone disease vary throughout the post-transplant period among persistent hyperparathyroidism, de novo hyperparathyroidism, and osteoporosis. The use of anti-resorptive therapies require understanding of different options and the clinical scenarios that warrant their use. With limited studies underscoring clinical events such as fractures, expert understanding of MBD physiology, and surrogate marker interpretation is needed to determine ideal and individualized therapy.
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Affiliation(s)
- Chandan Vangala
- Division of Nephrology and Solid-Organ Transplantation, Michael E. DeBakey VA Medical Center, Houston, TX, United States
| | - Jenny Pan
- Division of Nephrology and Solid-Organ Transplantation, Michael E. DeBakey VA Medical Center, Houston, TX, United States
| | - Ronald T Cotton
- Division of Abdominal Transplantation, Department of Surgery, Baylor College of Medicine, Houston, TX, United States
| | - Venkat Ramanathan
- Division of Nephrology and Solid-Organ Transplantation, Michael E. DeBakey VA Medical Center, Houston, TX, United States
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Abstract
Dysregulated phosphate metabolism is a common consequence of chronic kidney disease, and is characterized by a high circulating level of fibroblast growth factor (FGF)-23, hyperparathyroidism, and hyperphosphataemia. Kidney transplantation can elicit specific alterations to phosphate metabolism that evolve over time, ranging from severe hypophosphataemia (<0.5 mmol/l) to hyperphosphataemia (>1.50 mmol/l) and high FGF-23 levels. The majority of renal transplant recipients develop hypophosphataemia during the first 3 months after transplantation as a consequence of relatively slow adaptation of FGF-23 and parathyroid hormone levels to restored renal function, and the influence of immunosuppressive drugs. By 3-12 months after transplantation, phosphate homeostasis is at least partially restored in the majority of recipients, which is paralleled by a substantially reduced risk of cardiovascular-associated morbidity and mortality compared with the pre-transplantation setting. Many renal transplant recipients, however, exhibit persistent abnormalities in phosphate homeostasis, which is often due to multifactorial causes, and may contribute to adverse outcomes on the cardiovascular system, kidney, and bone. Dietary and pharmacologic interventions might improve phosphate homeostasis in renal transplant recipients, but additional insight into the pathophysiology of transplantation-associated abnormalities in phosphate homeostasis is needed to further optimize disease management and improve prognosis for renal transplant recipients.
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Srinivas NR. Therapeutic drug monitoring of cyclosporine and area under the curve prediction using a single time point strategy: appraisal using peak concentration data. Biopharm Drug Dispos 2015. [DOI: 10.1002/bdd.1967] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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Modeling approach for multiple transporters-mediated drug–drug interactions in sandwich-cultured human hepatocytes: Effect of cyclosporin A on hepatic disposition of mycophenolic acid phenyl-glucuronide. Drug Metab Pharmacokinet 2015; 30:142-8. [DOI: 10.1016/j.dmpk.2014.10.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2014] [Revised: 09/25/2014] [Accepted: 10/11/2014] [Indexed: 12/31/2022]
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Tillmann FP, Wächtler C, Hansen A, Rump LC, Quack I. Vitamin D and cinacalcet administration pre-transplantation predict hypercalcaemic hyperparathyroidism post-transplantation: a case-control study of 355 deceased-donor renal transplant recipients over 3 years. Transplant Res 2014; 3:21. [PMID: 25606342 PMCID: PMC4298997 DOI: 10.1186/s13737-014-0021-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2014] [Accepted: 12/08/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The effects of pre-transplantation medication for secondary hyperparathyroidism on post-transplantation parathyroid hormone (PTH) and calcium levels have not yet been conclusively determined. Therefore, this study sought to determine the level of off-label use of cinacalcet and to determine predictors of its administration during the long-term follow-up of a cohort of individuals who received deceased-donor renal transplants. Furthermore, safety considerations concerning the off-label use of cinacalcet are addressed. METHODS This was a case-control study of 355 stable renal transplant recipients. The patient cohort was divided into two groups. Transplant group A comprised patients who did not receive cinacalcet treatment, and transplant group B comprised patients who received cinacalcet treatment during follow-up after renal transplantation. The characteristics of the patients were evaluated to determine predictors of cinacalcet use after successful renal transplantation. RESULTS Compared with the control individuals (n = 300), the cinacalcet-treated individuals (n = 55) had significantly higher PTH levels at 4 weeks post-transplantation (20.3 ± 1.6 versus 40.7 ± 4.0 pmol/L, p = 0.0000) when they were drug naive. At 3.2 years post-transplantation, cinacalcet-treated patients showed higher PTH (26.2 ± 2.3 versus 18.4 ± 2.3 pmol/L, p = 0.0000), higher calcium (2.42 ± 0.03 versus 2.33 ± 0.01 mmol/L, p = 0.0045) and lower phosphate (0.95 ± 0.04 versus 1.06 ± 0.17 mmol/L, p = 0.0021) levels. Individuals in the verum group were more likely to receive cinacalcet therapy (45.5% versus 14.3%, p = 0.0000), and they had higher pill burdens for the treatment of hyperparathyroidism (1.40 ± 0.08 versus 0.72 ± 0.03 pills per patient, p = 0.0000) whilst they were on the waiting list for transplantation. Regression analysis confirmed the associations between hypercalcaemic hyperparathyroidism and PTH levels at 4 weeks post-transplantation (p = 0.0001), cinacalcet use (p = 0.0000) and the preoperative total pill burden (p = 0.0000). Renal function was the same in both groups. CONCLUSIONS Parathyroid gland dysfunction pre-transplantation translates into clinically relevant hyperparathyroidism post-transplantation, despite patients being administered more intensive treatment whilst on dialysis. PTH levels at 4 weeks post-transplantation might serve as a marker for the occurrence of hypercalcaemic hyperparathyroidism during follow-up.
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Affiliation(s)
- Frank-Peter Tillmann
- Klinik für Nephrologie, Heinrich Heine Universität Düsseldorf, Moorenstr. 5, D-40225, Düsseldorf, Germany
| | - Carolin Wächtler
- Klinik für Nephrologie, Heinrich Heine Universität Düsseldorf, Moorenstr. 5, D-40225, Düsseldorf, Germany
| | - Anita Hansen
- Klinik für Nephrologie, Heinrich Heine Universität Düsseldorf, Moorenstr. 5, D-40225, Düsseldorf, Germany
| | - Lars Christian Rump
- Klinik für Nephrologie, Heinrich Heine Universität Düsseldorf, Moorenstr. 5, D-40225, Düsseldorf, Germany
| | - Ivo Quack
- Klinik für Nephrologie, Heinrich Heine Universität Düsseldorf, Moorenstr. 5, D-40225, Düsseldorf, Germany
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Evenepoel P, Cooper K, Holdaas H, Messa P, Mourad G, Olgaard K, Rutkowski B, Schaefer H, Deng H, Torregrosa JV, Wuthrich RP, Yue S. A randomized study evaluating cinacalcet to treat hypercalcemia in renal transplant recipients with persistent hyperparathyroidism. Am J Transplant 2014; 14:2545-55. [PMID: 25225081 DOI: 10.1111/ajt.12911] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2014] [Revised: 05/15/2014] [Accepted: 05/18/2014] [Indexed: 01/25/2023]
Abstract
Persistent hyperparathyroidism (HPT) after kidney transplantation (KTx) is associated with hypercalcemia, hypophosphatemia and abnormally high levels of parathyroid hormone (PTH). In this randomized trial, cinacalcet was compared to placebo for the treatment of hypercalcemia in adult patients with persistent HPT after KTx. Subjects were randomized 1:1 to cinacalcet or placebo with randomization stratified by baseline corrected total serum calcium levels (≤11.2 mg/dL [2.80 mmol/L] or >11.2 mg/dL [2.80 mmol/L]). The primary end point was achievement of a mean corrected total serum calcium value<10.2 mg/dL (2.55 mmol/L) during the efficacy period. The two key secondary end points were percent change in bone mineral density (BMD) at the femoral neck and absolute change in phosphorus; 78.9% cinacalcet- versus 3.5% placebo-treated subjects achieved the primary end point with a difference of 75.4% (95% confidence interval [CI]: 63.8, 87.1), p<0.001. There was no statistical difference in the percent change in BMD at the femoral neck between cinacalcet and placebo groups, p=0.266. The difference in the change in phosphorus between the two arms was 0.45 mg/dL (95% CI: 0.26, 0.64), p<0.001 (nominal). No new safety signals were detected. In conclusion, hypercalcemia and hypophosphatemia were effectively corrected after treatment with cinacalcet in patients with persistent HPT after KTx.
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Affiliation(s)
- P Evenepoel
- Department of Nephrology and Renal Transplantation, University Hospitals Leuven, Leuven, Belgium
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Åsberg A, Midtvedt K, van Guilder M, Størset E, Bremer S, Bergan S, Jelliffe R, Hartmann A, Neely MN. Inclusion of CYP3A5 genotyping in a nonparametric population model improves dosing of tacrolimus early after transplantation. Transpl Int 2013; 26:1198-207. [PMID: 24118301 PMCID: PMC3852421 DOI: 10.1111/tri.12194] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2013] [Revised: 07/21/2013] [Accepted: 09/15/2013] [Indexed: 12/02/2022]
Abstract
Following organ engraftment, initial dosing of tacrolimus is based on recipient weight and adjusted by measured C0 concentrations. The bioavailability and elimination of tacrolimus are affected by the patients CYP3A5 genotype. Prospective data of the clinical advantage of knowing patient's CYP3A5 genotype prior to transplantation are lacking. A nonparametric population model was developed for tacrolimus in renal transplant recipients. Data from 99 patients were used for model development and validation. A three-compartment model with first-order absorption and lag time from the dosing compartment described the data well. Clearances and volumes of distribution were allometrically scaled to body size. The final model included fat-free mass, body mass index, hematocrit, time after transplantation, and CYP3A5 genotype as covariates. The bias and imprecision were 0.35 and 1.38, respectively, in the external data set. Patients with functional CYP3A5 had 26% higher clearance and 37% lower bioavailability. Knowledge of CYP3A5 genotype provided an initial advantage, but only until 3-4 tacrolimus concentrations were known. After this, a model without CYP3A5 genotype predicted just as well. The present models seem applicable for clinical individual dose predictions but need a prospective evaluation.
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Affiliation(s)
- Anders Åsberg
- Department of Pharmaceutical Biosciences, School of Pharmacy, University of Oslo, Oslo, Norway; Department of Transplant Medicine, Oslo University Hospital, Rikshospitalet, Oslo, Norway
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12
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Størset E, Holford N, Midtvedt K, Bremer S, Bergan S, Åsberg A. Importance of hematocrit for a tacrolimus target concentration strategy. Eur J Clin Pharmacol 2013; 70:65-77. [PMID: 24071959 PMCID: PMC3889505 DOI: 10.1007/s00228-013-1584-7] [Citation(s) in RCA: 88] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2013] [Accepted: 08/28/2013] [Indexed: 12/15/2022]
Abstract
Purpose To identify patient characteristics that influence tacrolimus individual dose requirement in kidney transplant recipients. Methods Data on forty-four 12-h pharmacokinetic profiles from 29 patients and trough concentrations in 44 patients measured during the first 70 days after transplantation (1,546 tacrolimus whole blood concentrations) were analyzed. Population pharmacokinetic modeling was performed using NONMEM 7.2®. Results Standardization of tacrolimus whole blood concentrations to a hematocrit value of 45 % improved the model fit significantly (p < 0.001). Fat-free mass was the best body size metric to predict tacrolimus clearance and volume of distribution. Bioavailability was 49 % lower in expressers of cytochrome P450 3A5 (CYP3A5) than in CYP3A5 nonexpressers. Younger females (<40 years) showed a 35 % lower bioavailability than younger males. Bioavailability increased with age for both males and females towards a common value at age >55 years that was 47 % higher than the male value at age <40 years. Bioavailability was highest immediately after transplantation, decreasing steeply thereafter to reach its nadir at day 5, following which it increased during the next 55 days towards an asymptotic value that was 28 % higher than that on day 5. Conclusions Hematocrit predicts variability in tacrolimus whole blood concentrations but is not expected to influence unbound (therapeutically active) concentrations. Fat-free mass, CYP3A5 genotype, sex, age and time after transplant influence the tacrolimus individual dose requirement. Because hematocrit is highly variable in kidney transplant patients and increases substantially after kidney transplantation, hematocrit is a key factor in the interpretation of tacrolimus whole blood concentrations. Electronic supplementary material The online version of this article (doi:10.1007/s00228-013-1584-7) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Elisabet Størset
- Department of Transplant Medicine, Oslo University Hospital, Rikshospitalet, Oslo, Norway,
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Verheyen N, Pilz S, Eller K, Kienreich K, Fahrleitner-Pammer A, Pieske B, Ritz E, Tomaschitz A. Cinacalcet hydrochloride for the treatment of hyperparathyroidism. Expert Opin Pharmacother 2013; 14:793-806. [DOI: 10.1517/14656566.2013.777041] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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14
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van de Steeg E, Greupink R, Schreurs M, Nooijen I, Verhoeckx K, Hanemaaijer R, Ripken D, Monshouwer M, Vlaming M, DeGroot J, Verwei M, Russel F, Huisman M, Wortelboer H. Drug-Drug Interactions between Rosuvastatin and Oral Antidiabetic Drugs Occurring at the Level of OATP1B1. Drug Metab Dispos 2012; 41:592-601. [DOI: 10.1124/dmd.112.049023] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
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Zhang R, Chouhan KK. Metabolic bone diseases in kidney transplant recipients. World J Nephrol 2012; 1:127-33. [PMID: 24175250 PMCID: PMC3782213 DOI: 10.5527/wjn.v1.i5.127] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/03/2011] [Revised: 06/01/2012] [Accepted: 09/25/2012] [Indexed: 02/06/2023] Open
Abstract
Metabolic bone disease after kidney transplantation has a complex pathophysiology and heterogeneous histology. Pre-existing renal osteodystrophy may not resolve completely, but continue or evolve into a different osteodystrophy. Rapid bone loss immediately after transplant can persist, at a lower rate, for years to come. These greatly increase the risk of bone fracture and vertebral collapse. Each patient may have multiple risk factors of bone loss, such as steroids usage, hypogonadism, persistent hyperparathyroidism (HPT), poor allograft function, metabolic acidosis, hypophosphatemia, vitamin D deficiency, aging, immobility and chronic disease. Clinical management requires a comprehensive approach to address the underlying and ongoing disease processes. Successful prevention of bone loss has been shown with vitamin D, bisphosphonates, calcitonin as well as treatment of hypogonadism and HPT. Novel approach to restore the normal bone remodeling and improve the bone quality may be needed in order to effectively decrease bone fracture rate in kidney transplant recipients.
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Affiliation(s)
- Rubin Zhang
- Rubin Zhang, Kanwaljit K Chouhan, Section of Nephrology, Department of Medicine, Tulane University School of Medicine, New Orleans, LA 70112, United States
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Amundsen R, Åsberg A, Ohm IK, Christensen H. Cyclosporine A- and tacrolimus-mediated inhibition of CYP3A4 and CYP3A5 in vitro. Drug Metab Dispos 2011; 40:655-61. [PMID: 22205779 DOI: 10.1124/dmd.111.043018] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Cyclosporine A (CsA) and tacrolimus (Tac) are immunosuppressive drugs used in the majority of patients with solid organ transplants, generally in combination with a wide range of drugs. CsA and Tac seem not only to be substrates of CYP3A but have also been described as inhibitors of CYP3A. For CsA, in particular, inhibition of CYP3A has been suggested as the main mechanism of interactions seen clinically with various drugs. The aim of this study was to investigate the inhibitory effect and inhibition characteristics of CsA and Tac on CYP3A4 and CYP3A5 in vitro and to evaluate its clinical relevance. Inhibition by CsA and Tac was studied using midazolam as the probe substrate in coincubation and preincubation investigations using human liver microsomes (HLMs) as well as specific CYP3A4- and CYP3A5-expressing insect microsomes (Supersomes). In vitro-in vivo extrapolations (IVIVEs) were performed to evaluate the clinical relevance of the inhibition. Both CsA and Tac competitively inhibited CYP3A in HLMs, showing inhibition constants (K(i)) of 0.98 and 0.61 μM, respectively. Experiments in Supersomes revealed that Tac inhibited both CYP3A4 and CYP3A5, whereas CsA only inhibited CYP3A4. In contrast to the HLM experiments, studies in Supersomes showed inhibition by Tac to be NADPH- and time-dependent, with a 5-fold reduction in IC(50) after preincubation, supporting a time-dependent inhibition mechanism in recombinant microsomes. By application of HLM data, IVIVE estimated the area under the concentration versus time curve of midazolam to increase by 73 and 27% with CsA and Tac, respectively. The inhibitory effect was predominantly on the intestinal level, whereas hepatic intrinsic clearance seemed unaffected.
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Affiliation(s)
- Rune Amundsen
- University of Oslo, School of Pharmacy, P.O. Box 1068 Blindern, 0316 Oslo, Norway.
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Guzzo I, Di Zazzo G, Laurenzi C, Ravà L, Giannone G, Picca S, Dello Strologo L. Parathyroid hormone levels in long-term renal transplant children and adolescents. Pediatr Nephrol 2011; 26:2051-7. [PMID: 21556715 DOI: 10.1007/s00467-011-1896-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/09/2010] [Revised: 03/14/2011] [Accepted: 03/15/2011] [Indexed: 12/26/2022]
Abstract
Secondary hyperparathyroidism is a common complication of chronic renal failure. Kidney transplantation corrects renal insufficiency and most metabolic abnormalities but hyperparathyroidism persists in 50% of children after transplantation. The aim of this study was to investigate parathyroid hormone (PTH) course and potential risk factors for hyperparathyroidism in children after renal transplant. We collected data from 145 transplanted children (mean follow-up 4.7 years). Intact PTH level (iPTH) rapidly decreased in the first 6 months post-transplant and continued to decline in the following years. iPTH was above the normal range in 69.1% of the patients at the time of transplant and in 47% 1 year later, this improvement continuing thereafter. Hypercalcemia was present in 20.3% of the patients before transplant and in 6.3 and 4.1% of patients 6 months and 1 year after transplant, respectively. Hypophosphatemia was present in 5.5% of the patients at 6 months, and 45.5% of the patients needed phosphorus supplements during the first 6 months after transplant. Multivariate analysis indicated pre-transplant hyperparathyroidism, dialysis duration, creatinine clearance and hypophosphatemia as predictors of persistent hyperparathyroidism. In kidney transplanted children, serum iPTH normalized in the long term in the majority of cases. Thus, parathyroidectomy should be reserved for selected patients.
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Affiliation(s)
- Isabella Guzzo
- Nephrology and Urology Department, Bambino Gesù Children's Hospital and Research Institute (IRCCS), Piazza S. Onofrio 4, 00165 Rome, Italy.
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Boulanger H, Haymann JP, Fouqueray B, Mansouri R, Metivier F, Mercadal L, Attaf D, Flamant M, Glotz D. [Cinacalcet impact on calcium homeostasis and bone remodeling in 13 renal transplanted patients with hyperparathyroidism and hypercalcaemia]. Nephrol Ther 2011; 8:47-53. [PMID: 21703956 DOI: 10.1016/j.nephro.2011.04.007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2009] [Revised: 04/19/2011] [Accepted: 04/19/2011] [Indexed: 11/26/2022]
Abstract
The purpose of the study is to assess the impact of cinacalcet on calcium and bone remodeling, in post-renal transplanted patients with persistent hypercalcaemia secondary to hyperparathyroidism. Thirteen renal-transplanted adult recipients with a glomerular filtration rate over 30 ml/min/1.73 m(2), a total serum calcium>2.60 mmol/l with ionized calcium>1.31 mmol/l and a parathyroid hormone serum level over 70 pg/ml, were treated with cinacalcet for 4 months followed by a 15-day wash out. The results show that cinacalcet lowers significantly total and ionized calcium respectively from 2,73 (2,67-2,86) to 2,31 (2,26-2,37) mmol/l (P<0.05) and from 1,39 (1,37-1,47) to 1,21 (1,15-1,22) mmol/l (P<0.05) with no alteration of the 24-hour urine calcium/creatinine ratio and no significant expected PTH serum level suppression (153 [115-214,9] and 166 [122-174] pg/ml). On the other hand, fasting urine calcium was significantly decreased from 0,61 (0,27-1,02) to 0,22 (0,15-0,37) (P<0.05) and bone-specific alkaline phosphatases increased from 20,5 (13-46,6) to 33,8 (12-58,9) ng/ml, upon cinacalcet treatment. After its discontinuation, all these effects were reversible. In conclusion, cinacalcet normalizes total and ionized calcium in renal-transplanted recipients with hypercalcemia secondary to hyperparathyroidism through a mechanism that could be independent of PTH serum level suppression. The increase in bone-specific alkaline phosphatases, biochemical markers of bone accretion and the significant decrease in fasting urine calcium suggest the possibility of a beneficial impact of cinacalcet on bone remodeling.
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Affiliation(s)
- Henri Boulanger
- Centre de néphrologie et d'hémodialyse, clinique de l'Estrée, 35, rue d'Amiens, 93240 Stains, France.
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Messa P, Cafforio C, Alfieri C. Clinical impact of hypercalcemia in kidney transplant. Int J Nephrol 2011; 2011:906832. [PMID: 21760999 PMCID: PMC3132802 DOI: 10.4061/2011/906832] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2011] [Revised: 03/31/2011] [Accepted: 04/20/2011] [Indexed: 12/20/2022] Open
Abstract
Hypercalcemia (HC) has been variably reported in kidney transplanted (KTx) recipients (5–15%). Calcium levels peak around the 3rd month after KTx and thereafter slightly reduce and stabilize. Though many factors have been claimed to induce HC after KTx, the persistence of posttransplant hyperparathyroidism (PT-HPT) of moderate-severe degree is universally considered the first causal factor. Though not proven, there are experimental and clinical suggestions that HC can adversely affect either the graft (nephrocalcinosis) and other organs or systems (vascular calcifications, erythrocytosis, pancreatitis, etc.). However, there is no conclusive evidence that correction of serum calcium levels might avoid the occurrence of these claimed clinical effects of HC. The best way to reduce the occurrence of HC after KTx is to treat as best we can the secondary hyperparathyroidism (SHP) during the uraemic stages. The indication to Parathyroidectomy (PTX), either before or after KTx, in order to prevent or to treat, respectively, HC after KTx, is still a matter of debate which has been revived by the availability of the calcimimetic cinacalcet for the treatment of PT-HPT. However, we still need to better clarify many points as regards the potential adverse effects related to either PTX or cinacalcet use in this clinical set, and we are waiting for the results of future randomized controlled trials to achieve some more definite conclusions on this topic.
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Affiliation(s)
- Piergiorgio Messa
- Nefrologia, Dialisi e Trapianto Renale, Ospedale Maggiore-Policlinico-Mangiagalli-Regina Elena, IRCCS, 20122 Milano, Italy
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20
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The effect of cinacalcet on bone remodeling and renal function in transplant patients with persistent hyperparathyroidism. Transplantation 2011; 91:560-5. [PMID: 21192318 DOI: 10.1097/tp.0b013e3182079431] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Parathyroidectomy is associated with renal functional losses in transplant patients; cinacalcet offers an attractive alternative. METHODS We performed a prospective observational study in 58 patients with persisting hyperparathyroidism after renal transplantation (Ca≥2.6 mmol/L) and impaired renal transplant function (estimated glomerular filtration rate [eGFR] <50 mL/min). The patients received 30 to 90 mg cinacalcet for 12 months with the target to normalize serum Ca. We measured parathyroid hormone (PTH), serum Ca, serum phosphorus, alkaline phosphatase, bone-specific alkaline phosphatase, osteocalcin, and telopeptide at 0, 1, 2, 3, 6, 9, and 12 months of cinacalcet treatment. Fractional excretion of calcium and phosphorus (n=24) were monitored at 0 and 1 month. RESULTS At inclusion, creatinine was 181±70 μmol/L, eGFR 43±19 mL/min, PTH 371±279 pg/mL, and Ca 2.73±0.22 mmol/L. We observed nephrocalcinosis in 58% of biopsied patients at enrollment. After cinacalcet, Ca decreased significantly and normalized at nearly any measurement. Phosphorus increased significantly at months 1, 9, and 12. PTH decreased significantly, but only at months 9 and 12 and did not normalize. Bone-specific alkaline phosphatase increased significantly (>normal) by month 12. eGFR decreased and serum creatinine increased at all time points. The Δ(creatinine) % increase correlated significantly with the Δ(PTH) % decrease at month 1 and 12. Telopeptide and alkaline phosphatase correlated with PTH and telopeptide also correlated with serum creatinine. CONCLUSION Calcium-phosphorus homeostasis in hypercalcemic renal transplant patients normalizes under cinacalcet and PTH decreases, albeit not to normal. The renal functional decline could be PTH mediated, analogous to the effects observed after parathyroidectomy.
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Messa P, Alfieri C, Brezzi B. Clinical utilization of cinacalcet in hypercalcemic conditions. Expert Opin Drug Metab Toxicol 2011; 7:517-28. [PMID: 21361849 DOI: 10.1517/17425255.2011.562196] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
INTRODUCTION Cinacalcet has recently been introduced as a treatment for secondary hyperparathyroidism in dialysis patients and for parathyroid carcinoma. However, there has been an increasing interest in finding out whether cinacalcet can be used as a treatment for other parathyroid hormone (PTH)-dependent hypercalcemic conditions also. AREAS COVERED The article reports the most relevant recent contributions dealing with calcium sensing receptor (CaSR) physiology as well as cinacalcet pharmacokinetics and pharmacodynamics. It also looks at the different hypercalcemic conditions where the use of cinacalcet has been proposed. This article was researched using clinical trials, case reports and outstanding basic research published in the last 3 years (MEDLINE database up to 31 November 2010). It provides the reader with an insight into the many unaddressed issues regarding cinacalcet that need to be resolved before it can be used in newly proposed fields. EXPERT OPINION Since cinacalcet may not only have an effect on parathyroid CaSR but also on CaSR expressed at bone and renal levels, it can currently only be considered a good alternative to parathyroidectomy in PTH-dependent hypercalcemic conditions when surgical intervention is burdened by a high failure rate or when it can be considered a risky procedure. At present, cinacalcet cannot be considered the first choice treatment in asymptomatic primary hyperparathyroidism or in mild-to-moderate forms of familial hypocalciuric hypocalcemia.
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Affiliation(s)
- Piergiorgio Messa
- Division of Nephrology, Dialysis, and Renal Transplant, Fondazione Ca' Granda-IRCCS, OspedaleMaggiore-Policlinico, v. Commenda 15, 20122 Milano, Italy.
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Copley JB, Germain M, Stern L, Pankewycz O, Katznelson S, Shah T, Wang O, Turner SA, Sprague SM. Evaluation of cinacalcet HCl treatment after kidney transplantation. Transplant Proc 2011; 42:2503-8. [PMID: 20832532 DOI: 10.1016/j.transproceed.2010.04.052] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2009] [Revised: 02/02/2010] [Accepted: 04/08/2010] [Indexed: 11/24/2022]
Abstract
BACKGROUND Hyperparathyroidism often remains or develops after kidney transplantation. Vitamin D sterol used as treatment for an elevated parathyroid hormone (PTH) level and associated bone disease may be contraindicated due to hypercalcemia. The calcimimetic cinacalcet HCl (cinacalcet), which lowers PTH and calcium (Ca) in chronic kidney disease patients, may represent an alternate therapeutic modality. METHODS This multicenter, retrospective, observational study examined 41 kidney transplant patients receiving cinacalcet for ≥3 months starting ≥3 months posttransplantation. Levels of intact PTH, Ca, and phosphorus (P) were examined during the assessment phase (3-6 months after initiation). RESULTS Median PTH decreased 21.8% during the assessment phase (P < .001), with 32.5% of patients exhibiting a ≥30% decrease in PTH from baseline. Median Ca decreased 6.8% (P < .0001). Median serum P rose 10.0% (P = .0124), but remained within normal limits. The estimated glomerular filtration rate was stable throughout the study. CONCLUSIONS Cinacalcet may be useful for the treatment of hyperparathyroidism after kidney transplantation. Randomized, prospectively designed clinical trials are required to confirm these results.
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Affiliation(s)
- J B Copley
- Cleveland Clinic Florida, Weston, Florida 33331, USA.
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Padhi D, Harris R. Clinical pharmacokinetic and pharmacodynamic profile of cinacalcet hydrochloride. Clin Pharmacokinet 2010; 48:303-11. [PMID: 19566113 DOI: 10.2165/00003088-200948050-00002] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Cinacalcet hydrochloride (cinacalcet) is a calcimimetic approved for the treatment of secondary hyperparathyroidism in patients with chronic kidney disease (CKD) receiving dialysis and for the treatment of hypercalcaemia in patients with parathyroid carcinoma. Following oral administration, peak plasma concentrations of cinacalcet occur within 2-6 hours. The absolute bioavailability is 20-25%, and administration of cinacalcet with low- or high-fat meals increases exposure (area under the plasma concentration-time curve from time zero to infinity [AUC(infinity)]) 1.5- to 1.8-fold. Cinacalcet has no significant interaction with calcium carbonate or sevelamer hydrochloride, phosphate binders commonly used in the treatment of patients with CKD receiving dialysis. The terminal elimination half-life is 30-40 hours, and steady-state concentrations are achieved within 7 days. The pharmacokinetics of cinacalcet are dose proportional over the dose range of 30-180 mg. The pharmacokinetic profile of cinacalcet is not notably affected by varying degrees of renal impairment. The pharmacokinetics of cinacalcet are comparable between healthy subjects, patients with primary hyperparathyroidism and patients with secondary hyperparathyroidism with reduced renal function (including those patients with secondary hyperparathyroidism receiving dialysis). Additionally, the pharmacokinetics of cinacalcet are similar in patients with secondary hyperparathyroidism receiving haemodialysis and patients with secondary hyperparathyroidism receiving peritoneal dialysis. Mild hepatic impairment does not affect the pharmacokinetics of cinacalcet, whereas moderate or severe hepatic impairment increases the exposure (AUC(infinity)) by approximately 2- and 4-fold, respectively. Age, sex, bodyweight and race do not notably affect the pharmacokinetics of cinacalcet. Cinacalcet is extensively metabolized by multiple hepatic cytochrome P450 (CYP) enzymes (primarily 3A4, 2D6 and 1A2) with <1% of the parent drug excreted in the urine. Dose adjustments of cinacalcet may be necessary, and parathyroid hormone (PTH) and serum calcium concentrations should be closely monitored if a patient initiates or discontinues therapy with a strong CYP3A4 inhibitor (e.g. ketoconazole, erythromycin, itraconazole). Cinacalcet is a strong inhibitor of CYP2D6; therefore, dose adjustment of concomitant medications that are predominantly metabolized by CYP2D6 and have a narrow therapeutic index (e.g. flecainide, vinblastine, thioridazine and most tricyclic antidepressants) may be required. Cinacalcet does not appreciably inhibit or induce the activities of CYP3A4, 1A2, 2C9 or 2C19. An inverse relationship exists between plasma PTH and cinacalcet concentrations. PTH concentrations are greatest before dose administration when the cinacalcet concentration is lowest (24 hours after the previous day's dose). Nadir PTH levels occur approximately 2-3 hours after dosing.
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Affiliation(s)
- Desmond Padhi
- Department of Medical Sciences, Amgen Inc., Thousand Oaks, California 91320, USA.
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Kuypers DRJ. Immunotherapy in elderly transplant recipients: a guide to clinically significant drug interactions. Drugs Aging 2009; 26:715-37. [PMID: 19728747 DOI: 10.2165/11316480-000000000-00000] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Currently, >50% of candidates for solid organ transplantation in Europe and the US are aged >50 years while approximately 15% of potential recipients are aged >or=65 years. Elderly transplant candidates are characterized by specific co-morbidity profiles that compromise graft and patient outcome after transplantation. The presence of coronary artery or peripheral vascular disease, cerebrovascular disease, history of malignancy, chronic obstructive lung disease or diabetes mellitus further increases the early post-transplant mortality risk in elderly recipients, with infections and cardiovascular complications as the leading causes of death. Not only are elderly patients more prone to developing drug-related adverse effects, but they are also more susceptible to pharmacokinetic and pharmacodynamic drug interactions because of polypharmacy. The majority of currently used immunosuppressant drugs in organ transplantation are metabolized by cytochrome P450 (CYP) or uridine diphosphate-glucuronosyltransferases and are substrates of the multidrug resistance (MDR)-1 transporter P-glycoprotein, the MDR-associated protein 2 or the canalicular multispecific organic anion transporter, which predisposes these immunosuppressant compounds to specific interactions with commonly prescribed drugs. In addition, important drug interactions between immunosuppressant drugs have been identified and require attention when choosing an appropriate immunosuppressant drug regimen for the frail elderly organ recipient. An age-related 34% decrease in total body clearance of the calcineurin inhibitor ciclosporin was observed in elderly renal recipients (aged >65 years) compared with younger patients, while older recipients also had 44% higher intracellular lymphocyte ciclosporin concentrations. Similarly, using a Bayesian approach, an inverse relationship was noted between sirolimus clearance and age in stable kidney recipients. Ciclosporin and tacrolimus have distinct pharmacokinetics, but both are metabolized by intestinal and hepatic CYP3A4/3A5 and transported across the cell membrane by P-glycoprotein. The most common drug interactions with ciclosporin are therefore also observed with tacrolimus, but the two drugs do not interact identically when administered with CYP3A inhibitors or inducers. The strongest effects on calcineurin-inhibitor disposition are observed with azole antifungals, macrolide antibacterials, rifampicin, calcium channel antagonists, grapefruit juice, St John's wort and protease inhibitors. Drug interactions with mycophenolic acids occur mainly through inhibition of their enterohepatic recirculation, either by interference with the intestinal flora (antibacterials) or by limiting drug absorption (resins and binders). Rifampicin causes a reduction in mycophenolic acid exposure probably through induction of uridine diphosphate-glucuronosyltransferases. Proliferation signal inhibitors (PSIs) such as sirolimus and everolimus are substrates of CYP3A4 and P-glycoprotein and have a macrolide structure very similar to tacrolimus, which explains why common drug interactions with PSIs are comparable to those with calcineurin inhibitors. Ciclosporin, in contrast to tacrolimus, inhibits the enterohepatic recirculation of mycophenolic acids, resulting in significantly lower concentrations and hence risk of underexposure. Therefore, when switching from tacrolimus to ciclosporin and vice versa or when reducing or withdrawing ciclosporin, this interaction needs to be taken into account. The combination of ciclosporin with PSIs requires dose reductions of both drugs because of a synergistic interaction that causes nephrotoxicity when left uncorrected. Conversely, when switching between calcineurin inhibitors, intensified monitoring of PSI concentrations is mandatory. Increasing age is associated with structural and functional changes in body compartments and tissues that alter absorptive capacity, volume of distribution, hepatic metabolic function and renal function and ultimately drug disposition. While these age-related changes are well-known, few specific effects of the latter on immunosuppressant drug metabolism have been reported. Therefore, more clinical data from elderly organ recipients are urgently required.
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Affiliation(s)
- Dirk R J Kuypers
- Department of Nephrology and Renal Transplantation, University Hospitals of Leuven, Leuven, Belgium.
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Falck P, Midtvedt K, Vân Lê TT, Storehagen L, Holdaas H, Hartmann A, Asberg A. A population pharmacokinetic model of ciclosporin applicable for assisting dose management of kidney transplant recipients. Clin Pharmacokinet 2009; 48:615-23. [PMID: 19725595 DOI: 10.2165/11313380-000000000-00000] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
BACKGROUND AND OBJECTIVE The pharmacokinetic disposition of ciclosporin shows great intra- and interpatient variability, and that combined with a narrow therapeutic window makes therapeutic drug monitoring of ciclosporin necessary. The nonlinear mixed-effects population pharmacokinetic program NONMEM predicts individual pharmacokinetic parameters based not only on individual patient observations but also on population characteristics and the patient's covariates. The aim of this model development is to potentially use it in the clinical setting to optimize ciclosporin dosing in renal transplant recipients. METHODS A population pharmacokinetic model of ciclosporin has been developed with NONMEM using full 12-hour pharmacokinetic profiles from 29 renal transplant recipients, 3 months of daily follow-up data from an additional 11 recipients, and both 3 months of follow-up data and full 12-hour pharmacokinetic profiles from nine patients. The internal validation of the model was based on data splitting and jack-knife methods. In addition, the model was validated for its clinical applicability on standard trough and 2-hour post-dose concentration data from 12 additional patients with 3 months of follow-up. RESULTS The model that best described the ciclosporin data was a two-compartment model with first-order absorption process with lagged time. The population pharmacokinetic parameters were oral clearance (CL/F) = 26.9 L/h; central volume of distribution after oral administration (V(1)/F) = 24.4 L; absorption rate constant (k(a)) = 0.544 h-1; lag time = 0.460 h; peripheral volume of distribution = 1119 L and intercompartmental clearance after oral administration (Q/F) = 19.6 L/h. Three covariates had significant effect on a total of six pharmacokinetic parameters. These were bodyweight on V(1)/F and k(a), time after transplantation on k(a), and age on CL/F, k(a) and V(1)/F. Cytochrome P450 3A5 genotype was also a significant covariate but was not included in the final model since such information is not available in clinical practice. The external validation showed that the model was able to predict ciclosporin concentrations in the 12 new patients with an average predictive error of 17.4 +/- 14% when the standard sample concentrations from the previous week were given. CONCLUSION A NONMEM pharmacokinetic model for ciclosporin in renal transplant recipients was successfully developed and validated for the first 3 months post-transplantation. The model showed good predictability in a new patient cohort. After further clinical validation, the model may be applicable as a clinical tool for optimizing ciclosporin dosing in renal transplant recipients in the early post-transplant period.
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Affiliation(s)
- Pål Falck
- Department of Pharmaceutical Biosciences, School of Pharmacy, University of Oslo, Oslo, Norway
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Messa P, Alfieri C, Brezzi B. Cinacalcet: pharmacological and clinical aspects. Expert Opin Drug Metab Toxicol 2009; 4:1551-60. [PMID: 19040330 DOI: 10.1517/17425250802587017] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
The calcium sensing receptor (CaSR) is expressed in cells secreting calcium-regulating hormones, in cells involved in calcium transport and in many other tissues, with an as yet not completely defined role. In parathyroid cells, the CaSR stimulation inhibits parathyroid hormone (PTH) secretion, synthesis and parathyroid cell proliferation. Cinacalcet belongs to calcimimetic type II compounds that can interact with CaSR, increasing its affinity for calcium. Clinical studies have proved cinacalcet to be effective in reducing calcium and PTH levels in primary hyperparathyroidism and in reducing PTH, calcium and phosphate in patients with secondary hyperparathyroidism owing to chronic renal failure, with a relatively safe profile, the only reported adverse events being hypocalcaemia and gastrointestinal symptoms. However, though calcimimetics do represent a real advancement in the field of the treatment of PTH secretion disturbances, there is a need for clinical trials, which should aim to demonstrate that a better control of biochemical parameters is also matched with better clinical outcomes.
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Affiliation(s)
- Piergiorgio Messa
- Nefrologia, Dialisi e Trapianto, Padiglione Croff, Ospedale Maggiore-Policlinico, v. Commenda 15, 20122 Milano, Italy.
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Padhi D, Salfi M, Emery M. Cinacalcet does not affect the activity of cytochrome P450 3A enzymes, a metabolic pathway for common immunosuppressive agents : a randomized, open-label, crossover, single-centre study in healthy volunteers. Drugs R D 2009; 9:335-43. [PMID: 18721002 DOI: 10.2165/00126839-200809050-00004] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022] Open
Abstract
BACKGROUND AND OBJECTIVE Cinacalcet HCl (cinacalcet) is approved for the treatment of secondary hyperparathyroidism in subjects receiving dialysis and for the reduction of hypercalcaemia in patients with parathyroid carcinoma. The drug may also be co-administered with medications used in the renal transplantation setting, such as immunosuppressants. Cinacalcet, as well as some immunosuppressants such as ciclosporin, tacrolimus and sirolimus, is partially metabolized by the cytochrome P450 3A enzymes (CYP3A). This study aimed to evaluate the potential inhibitory effects of cinacalcet on CYP3A activity using midazolam as a probe substrate in healthy volunteers. METHODS In this randomized, open-label, crossover, two-treatment, two-period, single-centre study, 12 healthy volunteers received either oral cinacalcet 90 mg once daily for 5 days plus a single oral dose of midazolam 2 mg on day 5, or a single oral dose of midazolam 2 mg on day 1. Following a 10-day washout period, subjects received the alternate treatment. Blood samples were collected predose and at selected time points up to 24 hours after dosing with midazolam for measurement of midazolam pharmacokinetic parameters. RESULTS Eleven subjects completed the study. Mean (standard deviation) midazolam maximum plasma concentrations (C(max)) and area under the plasma concentration-time curve from time zero to infinity (AUC(infinity)) were 9.31 (3.09) ng/mL and 24.1 (7.7) ng . h/mL, respectively, when administered in combination with cinacalcet, compared with 9.76 (2.81) ng/mL and 22.8 (6.1) ng . h/mL when administered alone. The mean geometric ratios (90% confidence interval) were 0.95 (0.84, 1.06) and 1.05 (0.95, 1.16) for C(max) and AUC(infinity), respectively. All adverse events were mild to moderate in severity, and consistent with the safety profile of cinacalcet. CONCLUSION Once-daily administration of cinacalcet did not alter the pharmacokinetics of midazolam relative to administration of midazolam alone. These data suggest that cinacalcet administration does not affect CYP3A activity, and thus would not have an effect on any drug eliminated via CYP3A, including some commonly used immunosuppressant therapies.
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Affiliation(s)
- Desmond Padhi
- Department of Medical Sciences, Amgen Inc., Thousand Oaks, California 91320, USA.
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28
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Evenepoel P. Calcimimetics in chronic kidney disease: evidence, opportunities and challenges. Kidney Int 2008; 74:265-75. [DOI: 10.1038/ki.2008.166] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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Kamar N, Gennero I, Spataru L, Esposito L, Guitard J, Lavayssière L, Cointault O, Gandia P, Durand D, Rostaing L. Pharmacodynamic effects of cinacalcet after kidney transplantation: once- versus twice-daily dose. Nephrol Dial Transplant 2008; 23:3720-6. [PMID: 18558623 DOI: 10.1093/ndt/gfn345] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
BACKGROUND In the setting of kidney transplantation, cinacalcet has been given, mainly, once daily, but also twice daily. The aims of this prospective study were to assess the acute pharmacodynamic effect of cinacalcet administrated once or twice daily to kidney transplant patients with normal renal function and persisting hypercalcaemia due to hyperparathyroidism and to evaluate 1-year efficacy and tolerance of cinacalcet given at a dose of 30 mg b.i.d. METHODS Eleven patients, who received a transplant 6 (6-59) months previously, were included in the study. A first kinetic was done after administration of 60 mg of cinacalcet at 8 a.m. After a washout period of 1 week, the second kinetic was performed with cinacalcet given at 30 mg b.i.d within a 12-h period. RESULTS During both kinetics, serum calcium (sCa), ionized calcium (sCa(2+)), albumin-corrected Ca and parathyroid hormone (PTH) levels decreased significantly. At 24 h after the second kinetic, sCa(2+) was significantly lower. After 1 year of cinacalcet treatment, given at the dose of 30 mg b.i.d., there was a significant decrease in sCa, sCa(2+), PTH levels and calcium x phosphorus (Ph) product. In contrast, Ph levels increased significantly. There was no significant change in renal function. CONCLUSION Once- or twice-daily acute administration of cinacalcet to kidney-transplant patients has similar efficacy. One-year administration of cinacalcet, given as two daily doses, is safe and efficient.
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Affiliation(s)
- Nassim Kamar
- Department of Nephrology, Dialysis and Multi-Organ Transplantation, Toulouse University Hospital, Toulouse, France.
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Schlieper G, Floege J. Calcimimetics in CKD-results from recent clinical studies. Pediatr Nephrol 2008; 23:1721-8. [PMID: 18594867 PMCID: PMC6901399 DOI: 10.1007/s00467-008-0900-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/20/2008] [Revised: 05/03/2008] [Accepted: 05/05/2008] [Indexed: 12/20/2022]
Abstract
Secondary hyperparathyroidism (sHPT) is a frequent complication in patients with chronic kidney disease (CKD) and a known contributor to the development of vascular calcification and renal osteodystrophy (CKD-BMD). Secondary hyperparathyroidism is also related to increased cardiovascular mortality in CKD patients. With the discovery that molecules can modulate the calcium-sensing receptor (CaR) of the parathyroid gland, new treatment options are now available to control sHPT. Calcimimetics activate the CaR and-by increasing its sensitivity to calcium-can effectively decrease parathyroid hormone (PTH) secretion. Calcimimetic treatment with cinacalcet has resulted in an effective lowering of PTH levels in both animal and clinical studies. Most clinical studies have been performed in dialysis patients, and only a few studies have been carried out in patients with CKD stage 3 & 4 and renal transplant patients. In haemodialysis patients with sHPT, cinacalcet treatment could increase the number of patients achieving National Kidney Foundation Kidney Disease Outcomes Quality Initiative targets (PTH, calcium, phosphate) compared to standard therapy. In stage 3 and 4 CKD patients, cinacalcet has been reported to reduce PTH levels, however, at the expense of increasing phosphate serum levels. Several small studies have reported that calcimimetics reduced PTH levels and hypercalcaemia after renal transplantation. In addition, two studies on paediatric dialysis patients with sHPT reported effective PTH lowering. This review summarizes recent clinical studies with cinacalcet treatment in CKD patients.
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Affiliation(s)
- Georg Schlieper
- Department of Nephrology and Clinical Immunology, RWTH University Hospital Aachen, Pauwelsstr. 30, 52074 Aachen, Germany
| | - Jürgen Floege
- Department of Nephrology and Clinical Immunology, RWTH University Hospital Aachen, Pauwelsstr. 30, 52074 Aachen, Germany
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