Blood Cyclosporine Concentrations Research Articles

LC-MS/MS and EMIT measure the whole blood concentration of cyclosporine A: The two methods yield concordant results within the dynamic range of the latter, but the former shows broader application scenarios

Cyclosporine A (CsA) is a widely used immunosuppressive drug with a narrow therapeutic index and large individual differences. Its therapeutic and toxic effects are closely related to blood drug concentrations, requiring routine therapeutic drug monitoring (TDM). The current main methods for TDM of CsA are enzyme multiplied immunoassay technique (EMIT) and liquid chromatography-tandem mass spectrometry (LC-MS/MS). However, few study on the method comparison of the EMIT and LC-MS/MS for the measurement of whole blood CsA concentration in children has been reported. In this study, we developed a simple and sensitive LC-MS/MS assay for the determination of CsA, and 657 cases of CsA concentrations were determined from 197 pediatric patients by a routine EMIT assay and by the validated in-house LC-MS/MS method on the same batch of samples, aimed to address the aforementioned concern. Consistency between the two assays was evaluated using linear regression and Bland-Altman analysis. The linear range of LC-MS/MS was 0.500–2000 ng/mL and that of the EMIT was 40–500 ng/mL, respectively. Overall, the correlation between the two methods was significant (r-value ranging from 0.8842 to 0.9441). Unsatisfactory consistency was observed in the concentrations < 40 ng/mL (r = 0.7325) and 200–500 ng/mL (r = 0.6851). Bland-Altman plot showed a mean bias of −18.0 % (±1.96 SD, −73.8 to 37.8 %) between EMIT and LC-MS/MS. For Passing-Bablok regression between EMIT and LC-MS/MS did not differ significantly (p > 0.05). In conclusion, the two methods were closely correlated, but the CsA concentration by LC-MS/MS assay was slightly higher than that by EMIT method. Switching from the EMIT assay to the LC-MS/MS method was acceptable, and the LC-MS/MS method will receive broader application in clinical settings due to its better analytical capabilities, but the results need to be further verified in different laboratories.

Effects of Triazole Antifungal Agents on the Plasma Concentration and Dosage of Cyclosporin in Patients with Aplastic Anaemia

Objectives. This study aimed to investigate the effects of different triazole antifungal agents on the blood concentration and dosage of cyclosporine (CsA) in patients with aplastic anaemia (AA). Methods. This retrospective study enrolled AA patients who received CsA and triazole antifungal agents simultaneously between January 2018 and December 2022. The ratio of CsA blood concentration (ng/mL) to dosage (mg/day) (C/D) co-administration with and without azoles was compared. The effects of different triazole antifungal agents on blood concentrations and dosages of CsA were analysed. Results. The mean C/D ratio of CsA increased 1.97 times when co-administered with posaconazole (POS), while the mean C/D ratio of CsA increased 1.76 times when co-administered with fluconazole (FCZ). Compared with CsA monotherapy, there was a significant difference in CsA concentrations among patients with azoles (P&lt;0.05). The mean dose of CsA decreased was 0.26 (−0.25—1.05) mg/kg/day and 0.18 (−0.50—0.69) mg/kg/day when co-administered with POS and FCZ, respectively. There is a wide interindividual variability in the magnitude of drug interaction between azoles and CsA. Conclusions. Although azoles increased CsA concentration, a wide individual variability was found in the patients with CsA C/D ratio. Therefore, the CsA dose should be adjusted by closely monitoring the blood levels of CsA co-administered with triazole antifungal agents. In addition, we observed that POS had a greater effect on the blood concentration of CsA than FCZ. When adjusting the dose of CsA in clinical practice, the blood concentration of CsA and the type of co-administered triazole antifungal agents should be considered.

Positive correlation between organic anion transporter 1B function indicated by plasma concentration of coproporphyrin-I and blood concentration of cyclosporin A in real-world patients.

Cyclosporin A (CyA) has potent inhibitory activity on organic anion transporting polypeptide 1B (OATP1B), causing drug-drug interactions with its substrate drugs. 3-carboxy-4-methyl-5-propyl-2-furanpropionate (CMPF), a uraemic toxin, has also been suggested to inhibit OATP1B activity. Recent study has identified coproporphyrin-I (CP-I) as a specific endogenous substrate for OATP1B, which is useful to indicate OATP1B activity. We investigated the relationship of CP-I with CyA and CMPF concentrations in patients taking CyA. In total, 121 blood samples from 74 patients who took CyA and underwent routine therapeutic drug monitoring were divided into trough and peak samples. CyA and CP-I concentrations were significantly higher in peak samples than in trough samples. A positive correlation between CP-I and CyA concentrations was found in all samples and in trough and peak samples, while no correlation was observed between CP-I and CMPF concentrations. Multiple regression analysis identified CyA and C-reactive protein concentrations as independent factors affecting CP-I concentration, with blood CyA concentration having markedly greater contribution to plasma CP-I concentration. The present study suggests that CyA inhibits OATP1B activity in a concentration-dependent manner in clinical setting, and that dose adjustment of OATP1B substrate drugs coadministered with CyA according to plasma CMPF concentration may not be necessary.

Antifungal Choice during Intravenous to Oral Cyclosporine Switch Effects Bioavailability in Patients Who Underwent Allogeneic Hematopoietic Stem Cell Transplantation

Introduction: Cyclosporine is a key drug during hematopoietic stem cell transplantation for the prevention of Graft-versus-Host disease with the potential for involvement in drug-drug interactions. We conducted this study to evaluate the effects of antifungals on cyclosporine blood levels and biavailability values. Material and Methods: Patients who had allogeneic hematopoietic stem cell transplantation with normal kidney and liver function and no other drug-drug interactions that could affect cyclosporine blood levels were included in the study. Patients were categorized into moderate (fluconazole) and strong (voriconazole, posaconazole) CYP3A4 inhibitor antifungal users and non-azole (amphotericin B, caspofungin) users. We collected intravenous and oral cyclosporine blood concentrations and doses during cyclosporine administration route changes and evaluated the effects of them according to antifungal groups. Results: We included 94 patients. The moderate and strong CYP3A4 inhibitor user numbers were 54 and 22, respectively. 18 patients with non-azole antifungal prescriptions were included. ANOVA revealed that there was a statistically significant difference in blood corrected concentrations (p<0.0001). The mean oral dose to intravenous dose ratio was 1.44 and 1.53 for the strong and moderate CYP3A4 inhibitor groups, respectively. This ratio was 1.51 for non-azole antifungal users. The median cyclosporine concentrations were higher after switching to oral cyclosporine in three antifungal groups. The highest mean cyclosporine concentration was 378,45 ng/mL and was obtained from patients with strong CYP3A4 inhibitor antifungals. The lowest mean cyclosporine concentration was observed in patients who were prescribed non-azole antifungals, which was subtherapeutic at 165,95 ng/mL. Bioavailability values were 1.17, 0.97, and 0.9 for moderate inhibitor, strong inhibitor, and non-azole users, respectively. In our study, the general oral dose to intravenous dose ratio regardless of the antifungal choice was 1.50. Despite having the lowest dose ratio (1.44), the highest bioavailability (1.17) was achieved by strong CYP3A4 inhibitor users, and nine of them experienced supratherapeutic cyclosporine levels. After applying a 1.53 dose ratio, the highest mean dose ratio among groups, the number of patients with supratherapeutic cylosporine levels increased to twenty-two from six. Eight patients with non-azole antifungal prescriptions still experienced subtherapeutic cyclosporine blood levels after the initiation of a 1.51 mean dose ratio, which suggests non-azole users may need higher oral cyclosporine doses (Figure 1). Conclusion: Cyclosporine is a gold medicine during the allogeneic hematopoeitic stem cell trasnplantation process. Concomitant antifungal therapy affects cyclosporine blood levels during cyclosporine administration.Patients who are prescribed non-azole antifungals such as caspofungin and amphotericin B are at an increased risk of Graft-versus-Host disease due to the lack of therapeutic cyclosporine levels. Patients with azole antifungals may face cyclosporine toxicities during cyclosporine route change due to hepatic enzyme inhibitions. For patients with strong CYP3A4 inhibitor antifungals such as voriconazole and posaconazole, the oral dose to intravenous dose ratio should be adjusted carefully to avoid toxicity. Fluconazole, a moderate CYP3A4 inhibitor, causes a wide range of cyclosporine blood levels, which makes it hard to advise strict dose ratios. Because patient responses to enzyme inhibitors varied in our study, we advise taking precautions on an individual basis. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

Applying machine learning to the pharmacokinetic modeling of cyclosporine in adult renal transplant recipients: a multi-method comparison.

Objective: The aim of this study was to identify the important factors affecting cyclosporine (CsA) blood concentration and estimate CsA concentration using seven different machine learning (ML) algorithms. We also assessed the predictability of established ML models and previously built population pharmacokinetic (popPK) model. Finally, the most suitable ML model and popPK model to guide precision dosing were determined. Methods: In total, 3,407 whole-blood trough and peak concentrations of CsA were obtained from 183 patients who underwent initial renal transplantation. These samples were divided into model-building and evaluation sets. The model-building set was analyzed using seven different ML algorithms. The effects of potential covariates were evaluated using the least absolute shrinkage and selection operator algorithms. A separate evaluation set was used to assess the ability of all models to predict CsA blood concentration. R squared (R 2) scores, median prediction error (MDPE), median absolute prediction error (MAPE), and the percentages of PE within 20% (F20) and 30% (F30) were calculated to assess the predictive performance of these models. In addition, previously built popPK model was included for comparison. Results: Sixteen variables were selected as important covariates. Among ML models, the predictive performance of nonlinear-based ML models was superior to that of linear regression (MDPE: 3.27%, MAPE: 34.21%, F20: 30.63%, F30: 45.03%, R 2 score: 0.68). The ML model built with the artificial neural network algorithm was considered the most suitable (MDPE: -0.039%, MAPE: 25.60%, F20: 39.35%, F30: 56.46%, R 2 score: 0.75). Its performance was superior to that of the previously built popPK model (MDPE: 5.26%, MAPE: 29.22%, F20: 33.94%, F30: 51.22%, R 2 score: 0.68). Furthermore, the application of the most suitable model and the popPK model in clinic showed that most dose regimen recommendations were reasonable. Conclusion: The performance of these ML models indicate that a nonlinear relationship for covariates may help to improve model predictability. These results might facilitate the application of ML models in clinic, especially for patients with unstable status or during initial dose optimization.

Pharmacotherapy in a Multidisciplinary Paediatric Hospital: Polypharmacy and Drug–Drug Interaction Risk Illustrated with a Clinical Case

Nowadays, the problems caused by polypharmacy are recognised and widely discussed in the medical community. Multimorbidity, which is not uncommon in paediatric practice, comes with an increase in the number of prescriptions and necessitates an active search for tools to reduce the potential risk and frequency of adverse drug–drug interactions in paediatric patients.The aim of the study was to use a clinical case to illustrate the need for monitoring, including laboratory monitoring of pharmacokinetic parameters, during concomitant therapy in paediatric practice.Materials and methods: the study consisted in a retrospective analysis of the archived medical records of an 11-year-old child with nephrotic syndrome associated with a concomitant tuberculous process who had been receiving inpatient treatment with immunosuppressants at the Russian Children’s Clinical Hospital from May to July 2018.Results: the prescription of cyclosporine for nephrotic syndrome entailed monitoring of plasma drug levels for potential pharmacokinetic interactions with the medicinal products used to treat the concomitant disease. The monitoring revealed an interaction between cyclosporine and rifampicin at the level of biotransformation. An adjustment of the concomitant therapy (discontinuation of rifampicin) allowed for achieving the target blood cyclosporine concentration, decreasing proteinuria and hypercholesterolemia, and increasing the blood total protein level in the child, which indicated the effectiveness of the ongoing treatment for the chief complaint.Conclusions: the data obtained suggest that laboratory monitoring of pharmacokinetic parameters in paediatric polypharmacy can increase the effectiveness of therapy and prevent adverse reactions and irrational combination of medicinal products.

Pharmacokinetics and bioequivalence of two cyclosporine oral solution formulations in cats.

The pharmacokinetic profiles and bioequivalence of two cyclosporine oral solutions were investigated in cats. Twenty-four cats were randomly allocated to two equally sized treatment groups in a randomized four-cycle, and dual-sequence cross-over design. Test and reference articles were orally administered in a single dose of 7 mg/kg Bodyweight. Serial blood samples were collected, and blood cyclosporine concentration was determined by ultra-performance liquid chromatography-mass spectrometry (UPLC-MS/MS). No significant differences were present in the major pharmacokinetic parameters (Cmax, AUC0−last,) between the two formulations. The blood profiles of cyclosporine following the administration of both formulations were similar. The findings of the study suggested that the two articles were bioequivalent for cyclosporine oral solution.

Effect of Itraconazole and Its Metabolite Hydroxyitraconazole on the Blood Concentrations of Cyclosporine and Tacrolimus in Lung Transplant Recipients.

Invasive Aspergillus infection is a major factor for poor prognosis in patients receiving lung transplantation (LT). An antifungal agent, itraconazole (ITCZ), that has antimicrobial activity against Aspergillus species, is used as a prophylactic agent against Aspergillus infection after LT. ITCZ and its metabolite, hydroxyitraconazole (OH-ITCZ), potently inhibit CYP3A and P-glycoprotein that metabolize or excrete calcineurin inhibitors (CNIs), which are the first-line immunosuppressants used after LT; thus, concomitant use of ITCZ and CNIs could induce an increase in the blood concentration of CNIs. However, no criteria for dose reduction of CNIs upon concomitant use with ITCZ in LT recipients have been defined. In this study, the effect of ITCZ and OH-ITCZ on the blood concentrations of two CNIs, tacrolimus and cyclosporine, after LT were retrospectively evaluated. A total of 39 patients who received LT were evaluated. Effects of ITCZ and OH-ITCZ on the concentration/dosage (C/D) ratio of tacrolimus and cyclosporine were analyzed using linear mixed-effects models. The plasma concentrations of OH-ITCZ were about 2.5-fold higher than those of ITCZ. Moreover, there was a significant correlation between the plasma concentrations of ITCZ and OH-ITCZ. Based on parameters obtained in the linear regression analysis, the C/D ratios of cyclosporine and tacrolimus increase by an average of 2.25- and 2.70-fold, respectively, when the total plasma concentration of ITCZ plus OH-ITCZ is 1000 ng/mL. In conclusion, the plasma levels of ITCZ and OH-ITCZ could be key factors in drawing up the criterion for dose reduction of CNIs.

Effect of Wuzhi capsules on cyclosporine A concentration in children with aplastic anemia immunotherapy: a single-center observational study

ABSTRACT Objective This research aimed to assess the effect of Wuzhi capsules (WZC) on the blood concentration of cyclosporine A (CsA) in renal aplastic anemia recipients. Methods This observational study was carried out at the Hematology Oncology Center, Beijing Children’s Hospital between November 2019 and February 2020. A total of 102 Chinese AA recipients receiving CsA (6 mg/kg/d) with or without WZC were included in this study. Baseline data, such as age, therapeutic drug monitoring data, and follow-up information were collected. The promotion concentration of CsA was calculated, and the pharmaceutical economics evaluation with combination of two drugs was also carried out. Results Dose- and body weight-adjusted trough concentrations (C0/D/W) of CsA in the WZC group were found to be significantly higher than that in the non-WZC group (P < 0.01). The average C0 of CsA increased by (63.27 ± 45.81) ng/mL. The incidence of adverse events was also not statistically significant between the two groups (P > 0.05). Conclusion WZC can increase CsA concentration without increasing adverse drug reactions. Efficient and convenient immunosuppressive effects on AA recipients can be achieved via immunosuppressant therapy in combination with WZC.

Analysis of the variable factors affecting changes in the blood concentration of cyclosporine before and after transfusion of red blood cell concentrate

BackgroundThe blood concentration of cyclosporine (CyA) is frequently elevated following the transfusion of red blood cell concentrate (RCC) to patients after allogeneic hematopoietic stem cell transplantation (HSCT). The aim of this retrospective study was to identify the variable factors affecting changes in the blood concentration of CyA before and after transfusion of RCC.MethodsWe enrolled 105 patients (age, 5–66 years) who received both CyA and transfusion after HSCT. The ratio of the measurement after transfusion to the measurement before transfusion was calculated for the hematocrit and blood concentration/dose ratio of CyA (termed the HCT ratio and the CyA ratio, respectively).ResultsThe blood concentration/dose ratio of CyA was increased after transfusion compared with before transfusion (P < 0.001). The HCT ratio was significantly correlated with the CyA ratio (P = 0.23, P < 0.001). The HCT ratio, concomitant medication that could elevate CyA concentration after RCC transfusion, and difference in the alkaline phosphatase level between before and after transfusion (ΔALP) were explanatory variables associated with the variation in the CyA ratio. There was no correlation between the CyA concentration after transfusion and the change in the estimated glomerular filtration rate.ConclusionsA change in the blood concentration/dose ratio of CyA was found to be associated with a change in the HCT, concomitant medication that could elevate CyA concentration after RCC transfusion, and ALP levels. If the HCT level rises significantly after RCC transfusion, clinicians and pharmacists should pay attention to changes in the blood CyA concentration.

Unexpected overdose of oral cyclosporine in a kidney transplant patient: a case report

Cyclosporine is a widely used immunosuppressive agent to prevent rejection of solid organ transplant. Here, we describe the case of a 71-year-old man who received the prescribed dose of cyclosporine...

Therapeutic Drug Monitoring of Cyclosporine Using Single Sampling Strategy

Cyclosporine is mainly used as Immunosuppressant after different kinds of transplantation including bone marrow, lungs, kidneys, liver, heart, and other types of organ transplantations. Immunosuppressants diminish organ rejection and elongate the survival of the transplanted organs. Due to the narrow therapeutic ranges and significantly&#x0D; high interindividual and intraindividual variability in blood levels of cyclosporine, there is essential and vital need of therapeutic drug monitoring (TDM) of this drug in order to maintain the patient within the required therapeutic concentrations, which consequently lead to optimizing the clinical outcome and decrease the hazard of toxicity or rejection following organ transplantations. The current review article was aimed to present data for using a single or possibly two blood sampling strategy to be used for TDM of cyclosporine in order to assess the optimal blood levels of cyclosporine used in organ transplant recipients. The results showed that steady state blood concentration of cyclosporine obtained after 2 hours (C2) and possibly after 3 hours (C3) of drug administration are the best sampling time points which reflect total drug exposure (area under blood concentration versus time curve=AUC) and consequently reflecting the effect and the adverse effect(s) of cyclosporine. On the other hand, blood samples obtained at other time points particularly steady state trough concentration obtained before the next dose (C0) demonstrated poor correlation with total drug exposure and consequently the clinical outcome of the drug. Moreover, this study also demonstrated that for organs transplantations TDM of cyclosporine and assessing the clinical conditions of the patients should be routinely performed in order to adjust the dose to get optimal effect and to diminish the adverse effects of the drug. This review article focused on the findings which indicated that monitoring steady-state blood levels of cyclosporine after 2 hours (C2) and likely after 3 hours (C3) of drug intake may be used as ideal surrogate index in TDM of cyclosporine and for predicting the clinical outcome of the drug in all and different types of organs transplantations.

Low cyclosporine concentrations in children and time to acute graft versus host disease

BackgroundAchievement of target blood concentrations of cyclosporine (CsA) early after transplantation is known to be highly effective for reducing the incidence of acute graft versus host disease (aGVHD). However, no research has been conducted for predicting aGVHD occurrence with low CsA concentrations at different time periods. The objective of this study was to investigate the risk of aGVHD according to low CsA concentrations at lag days in children with allogenic hematopoietic stem cell transplantation (HSCT).MethodsThe records of 61 consecutive children who underwent allogeneic HSCT and received CsA as prophylaxis against aGVHD between May 2012 and March 2015 were retrospectively evaluated. The main outcome was any association between low CsA concentrations at lag days and aGVHD occurrence, which was examined for the first month after transplantation. Mean CsA concentrations at three lag periods were calculated: lag days 0–6, 7–13, and 14–20 before aGVHD occurrence.ResultsPatients whose mean CsA concentrations at lag days 0–6 did not reach the initial target concentration had 11.0-fold (95% confidence interval [CI]: 2.3–51.9) greater incidence of aGVHD. In addition, the AORs of low CsA concentrations at lag days 7–13 and 14–20 for developing aGVHD were 108.2 (95% CI: 7.7–1515.5) and 12.1 (95% CI: 1.1–138.1), respectively.ConclusionsAfter low CsA concentrations are detected, careful attention needs to be paid to prevent aGVHD.

Therapeutic Drug Monitoring of Cyclosporine Using Single Sampling Strategy

Cyclosporine is mainly used as Immunosuppressant after different kinds of transplantation including bone marrow, lungs, kidneys, liver, heart, and other types of organ transplantations. Immunosuppressants diminish organ rejection and elongate the survival of the transplanted organs. Due to the narrow therapeutic ranges and significantly high interindividual and intraindividual variability in blood levels of cyclosporine, there is essential and vital need of therapeutic drug monitoring (TDM) of this drug in order to maintain the patient within the required therapeutic concentrations, which consequently lead to optimizing the clinical outcome and decrease the hazard of toxicity or rejection following organ transplantations. The current review article was aimed to present data for using a single or possibly two blood sampling strategy to be used for TDM of cyclosporine in order to assess the optimal blood levels of cyclosporine used in organ transplant recipients. The results showed that steady state blood concentration of cyclosporine obtained after 2 hours (C2) and possibly after 3 hours (C3) of drug administration are the best sampling time points which reflect total drug exposure (area under blood concentration versus time curve=AUC) and consequently reflecting the effect and the adverse effect(s) of cyclosporine. On the other hand, blood samples obtained at other time points particularly steady state trough concentration obtained before the next dose (C0) demonstrated poor correlation with total drug exposure and consequently the clinical outcome of the drug. Moreover, this study also demonstrated that for organs transplantations TDM of cyclosporine and assessing the clinical conditions of the patients should be routinely performed in order to adjust the dose to get optimal effect and to diminish the adverse effects of the drug. This review article focused on the findings which indicated that monitoring steady-state blood levels of cyclosporine after 2 hours (C2) and likely after 3 hours (C3) of drug intake may be used as ideal surrogate index in TDM of cyclosporine and for predicting the clinical outcome of the drug in all and different types of organs transplantations.

Excessive Cyclosporine-Associated Immunosuppression in a Dog Heterozygous for the MDR1 (ABCB1-1Δ) Mutation

Pharmacodynamic monitoring was used to titrate cyclosporine dosing in a dog with immune-mediated hemolytic anemia. Development of a suspected secondary infection, with subsequent discovery of an unexpectedly high level of T-cell suppression despite a relatively low cyclosporine dose, prompted an investigation into the cause of possible excessive immunosuppression. Blood cyclosporine concentrations were within expected target ranges, and the dog was determined to be heterozygous for the multidrug resistance protein 1 (MDR1; ATP-binding cassette sub family B member 1-1Δ) gene mutation. The MDR1 mutation was suspected to have contributed to the excessive immunosuppression experienced by this patient. This case highlights the need to monitor immunosuppressive therapy in the individual patient, especially when the patient is not responding to therapy at typical dosages or when secondary infections develop at dosages lower than expected to cause significant immunosuppression. Pharmacodynamic monitoring can be used to help identify unexpected excessive immunosuppression in dogs receiving cyclosporine, and MDR1 genotyping should be further explored as a potential method of predicting and preventing its occurrence.

Relationship between allograft cyclosporin concentrations and P-glycoprotein expression in the 1st month following renal transplantation.

The immunosuppressant cyclosporin is a P-glycoprotein (P-gp) substrate whose impaired function has been associated with an increased risk of cyclosporin-induced nephrotoxicity following renal transplantation. This study investigated the relationship between blood and allograft cyclosporin concentration, and the effect of P-gp expression. Fifty biopsy samples were obtained from 39 renal transplant recipients who received cyclosporin as part of maintenance immunosuppression. Blood cyclosporin concentrations (2hours postdose) were obtained from clinical records, matching allograft cyclosporin concentrations were measured in frozen biopsy tissue by liquid chromatography-tandem mass spectrometry, and allograft P-gp expression was assessed by immunohistochemistry. Blood and allograft cyclosporin concentrations in the 1st month post-transplantation ranged from 505-2005μg/L and 0.01-16.7ng/mg tissue, respectively. Dose was the only significant predictor of allograft cyclosporin concentrations (adjusted R2 =.24, F-statistic=11.52, P=.0019), with no effect of P-gp expression or blood cyclosporin concentrations. P-gp expression is not the major determinant of allograft cyclosporin concentrations.

Cyclosporine Metabolites' Metabolic Ratios May Be Markers of Cardiovascular Disease in Kidney Transplant Recipients Treated with Cyclosporine A-Based Immunosuppression Regimens.

Cardiovascular disease (CVD) remains one of the primary causes of death after kidney transplantation (KTX). Cyclosporine (CsA) metabolites may play a role in CVD. Metabolic ratio (MR) may be considered a measure of intra-individual differences of CsA metabolism. The study was aimed at analysis of associations of CVD with indices of CsA metabolism: MRs and dose-adjusted CsA concentrations (C/D and C/D/kg). The study was performed in the Department of Immunology, Transplant Medicine, and Internal Diseases of the Medical University of Warsaw and involved 102 KTX recipients. Whole blood concentrations of cyclosporine A, AM1, AM9, AM4N, demethylcarboxylated (dMC-CsA), dihydroxylated (DiH-CsA), trihydroxylated (TriH-CsA) cyclosporine metabolites were determined by liquid chromatography coupled with tandem mass spectrometry. Lower AM9/CsA were observed in diabetics. Patients with coronary disease and/or myocardial infarction had lower dMC-CsA/CsA and higher AM4N/CsA. Supraventricular arrhythmia (SVA) was associated with higher AM1/CsA and AM4N/CsA. Hypertriglyceridemia (hTG) was associated with lower AM9/CsA, higher C/D and C/D/kg. Decrease of AM9/CsA and AM4N and higher D/C were associated with overweight/obesity. Systolic blood pressure (BP) positively correlated with dMC-CsA/CsA and negatively with C/D/kg. Diastolic BP correlated positively with AM1/CsA, dMC-CsA/CsA, DiH-CsA/CsA and TriH-CsA/CsA. We have demonstrated the association of coronary disease/myocardial infarction, SVA, hTG, overweight/obesity and elevated arterial BP with higher MRs of AM1, AM4N, dMC-CsA, DiH-CsA and TriH-CsA, and lower MRs of AM9, which may indicate deleterious and favourable effects of individual CsA metabolites on cardiovascular system and suggest engagement of specific enzymatic pathways.

Cardiovascular Disease in Kidney Transplantation and Its Association With Blood Concentrations of Cyclosporine and Cyclosporine Metabolites

Cyclosporine A (CsA) is the first calcineurin inhibitor used as immunosuppressive agent. Its administration is associated with multiple adverse effects including cardiovascular diseases (CVDs), but their mechanisms have not been fully elucidated. Cyclosporine metabolites are not well studied in this context. This study was aimed at analysis of the incidence of CVDs and their association with concentrations of cyclosporine and its metabolites.Sixty patients after kidney transplantation (KTX) taking an immunosuppressive regimen including CsA participated in the study. There were 22 women (36.67%) and 38 men (63.33%), mean age 51.73 years, mean 109.38 months after KTX.We observed a correlation between mean diastolic blood pressure and concentrations of metabolite to parent drug ratios of AM1-CsA/CsA (r = 0.35, P = .006), dihydroxy-CsA/CsA (r = 0.42, P = .001), trihydroxy-CsA/CsA (r = 0.42; P = .003) and desmethyl-carboxy-CsA/CsA (r = 0.65, P = .003). There were no significant associations of other CsA metabolites' parameters with CVDs (coronary disease, hypertension, stroke, arrhythmia, diabetes mellitus, obesity).Study results suggest that blood pressure increases associated with CsA therapy could be caused by CsA metabolites that influence mainly diastolic blood pressure levels. A lack of such differences in relation with other CVDs may suggest that more complex mechanisms are involved in the development of cardiovascular injury and disease after kidney transplantation.

Activation of P-glycoprotein and CYP 3A by Coptidis Rhizoma in vivo: Using cyclosporine as a probe substrate in rats

Coptidis Rhizoma (CR), the rhizome of Coptis chinensis FRANCH, is a popular Chinese herb. CR contains plenty of isoquinoline alkaloids such as berberine, coptisine and palmatine. Cyclosporine (CSP), an important immunosuppressant with narrow therapeutic window, is employed as a probe substrate of P-glycoprotein (P-gp) and CYP3A4 in order to investigate the in vivo modulation effect of CR on P-gp and CYP3A4. Three groups of rats were orally administered CSP without and with single dose or repeated dosing of CR in a parallel design. Blood samples were collected at specific time points and the blood CSP concentration was determined by a specific monoclonal fluorescence polarization immunoassay. The results showed that a single dose (1.0 g/kg) and the 7th dose (1.0 g/kg) of CR significantly decreased the Cmax of CSP by 56.9% and 70.4%, and reduced the AUC0-540 by 56.4% and 68.7%, respectively. Cell study indicated that CR decoction, berberine, coptisine, palmatine all activated the efflux transport of P-gp. Ex-vivo study showed that the serum metabolites of CR activated CYP 3A4. In conclusion, through using CSP as an in vivo probe substrate, we have verified that oral intake of CR activated the functions of P-gp and CYP3A based on in vivo and in vitro studies.

Detection of ATP Level in CD4+ T Lymphocytes and Its Clinical Significance in Allogeneic Hematopoietic Stem Cell Transplantation Recipients

To explore the clinical value of detecting adenosine triphosphate (ATP) level in CD4+ T lymphocytes (Immuknow ATP) of patients on early stage after allogeneic hematopoietic stem cell transplantation (allo-HSCT). The base-line ATP value in CD4+ T lymphocytes in cases of hematological malignancies and the ATP level in CD4+ T lymphocytes of acute leukemia patients before allo-HSCT were detected. Allo-HSCT recipients were devided into 3 groups with different level of immunereactivity according to ATP concentraiton in month 3 (day 90±5) after allo-HSCT. The clinical characteristics of patients in 3 groups were analyzed. The mass concentration of Immuknow ATP in 15 cases of hematological malignancies before allo-HSCT ranged from 56.21-435.71 ng/ml, with a mean of 203.98±112.72 ng/ml. The ATP level in 46 cases after allo-HSCT ranged from 1.69-333.09 ng/ml, with a median of 41.96 ng/ml. Both 91.26 ng/ml (mean-SD) and 316.70 ng/ml (mean+SD) were used as cutoff, and 36 allo-HSCT recipients (78.3%) were assigned to low immunereactivity group, 8 recipients (17.4%) to middle group and 2 recipients (4.3%) to high group. The incidence of infection in low immunereactivity group was significantly higher than that in middle immunereactivity group (86.1% vs 50.0%)(P=0.022), and also significantly higher than that in high immunereactivity group (86.1% vs 0%)(P=0.002). There were no statistical differences in the incidences of severe infection among 3 groups. The incidence of grade II or higher acute graft versus host disease (aGVHD) in high immunereactivity group was superior to that in low immunereactivity group statistically (100% vs 13.9%)(P=0.002). Immune-mediated organ injury occurred more frequently in high immunereactivity group as compared with low and middle immunereactivity groups (100% vs 0% and vs 0%)(P=0.000; P=0.002). There were no significant differences in relapse rates of leukemia among 3 groups. The percentage of patients with increased trough blood concentration of cyclosporine A(CsA) was not significantly different among 3 groups (P=0.720). Detection of ATP level in CD4+ T lymphocytes on early stage after allo-HSCT possesses clinical significance for predicting infection, severity at aGVHD and immune-mediated organ injury.