Blood CsA Concentrations Research Articles

Early Tapering of Cyclosporine Is Feasible in Haploidentical Stem Cell Transplantation: A Single Center Experience.

Cyclosporine-A (CsA) and post transplantation cyclophosphamide (PTCy) are common agents used for graft versus host disease (GVHD) prophylaxis in Haploidentical hematopoietic cell transplantation (haplo-HCT). However, the impact of CsA cessation timing in the posttransplant setting on clinical outcomes is uncertain. We aimed to investigate the impact of a novel approach that integrated early CsA cessation with PTCy utilization. This study was a single arm retrospective study carried out at a tertiary referral hospital hematology and bone marrow transplantation center between 2009 and 2022. The patients who received haplo-HCT with ATG, PTCy and CsA as GVHD prophylaxis were included. CsA was planned for cessation starting at day 45 to day 60. Acute and chronic GVHD were evaluated and graded. CsA blood concentrations and its impact on acute and chronic GVHD was evaluated. Thirty-one patients composed of 19 (61.3%) male and 12 (38.7%) female patients with a median age of 31 years (20-58). Busulfan and TBI based conditioning regimens were the most utilized regimens. The majority of donors were first degree relatives. Stem cell origin was peripheral blood for all patients. GVHD prophylaxis consisted of ATG, CsA and PTCy. Acute GVHD was observed in 9 (29%) cases, whereas chronic GVHD was seen in 3 (9.7%) cases, with 2 of them having overlapping GVHD. Age, gender, number of chemotherapy lines, transplant characteristics, infused CD34 cell count, and engraftment durations were similar among patients with and without GVHD. Patients with GVHD had similar 1st, 2nd, 3rd and 4th week CsA concentrations compared to patients without GVHD (p>0.05). The presence of GVHD was not associated with worse progression free survival and overall survival (p=0.6, p=0.5, respectively). CMV reactivation was more common in the GVHD group. In the current study, we did not find an impact of CsA concentration on GVHD and post-transplant outcomes in Haplo-HCT setting. Therefore, together with the use of PTCy, early CsA cessation can be an option; further studies are needed to understand all aspects of this approach.

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.

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.

Monitoring of Ex Vivo Cyclosporin a Activity in Healthy Volunteers Using T Cell Function Assays in Relation to Whole Blood and Cellular Pharmacokinetics.

Therapeutic drug monitoring (TDM) of calcineurin inhibitors (i.e., tacrolimus and cyclosporin A) is standard of care after solid organ transplantation. Although the incidence of acute rejection has strongly decreased, there are still many patients who experience severe side effects or rejection after long-term treatment. In this healthy volunteer study we therefore aimed to identify biomarkers to move from a pharmacokinetic-based towards a pharmacodynamic-based monitoring approach for calcineurin inhibitor treatment. Healthy volunteers received a single dose of cyclosporine A (CsA) or placebo, after which whole blood samples were stimulated to measure ex vivo T cell functionality, including proliferation, cytokine production, and activation marker expression. The highest whole blood concentration of CsA was found at 2 h post-dose, which resulted in a strong inhibition of interferon gamma (IFNy) and interleukin-2 (IL-2) production and expression of CD154 and CD71 on T cells. Moreover, the in vitro effect of CsA was studied by incubation of pre-dose whole blood samples with a concentration range of CsA. The average in vitro and ex vivo CsA activity overlapped, making the in vitro dose–effect relationship an interesting method for prediction of post-dose drug effect. The clinical relevance of the results is to be explored in transplantation patients on calcineurin inhibitor treatment.

Effect of posaconazole on the concentration of intravenous and oral cyclosporine in patients undergoing hematopoietic stem cell transplantation.

This study aimed to investigate the interactions between posaconazole (POS) and intravenously/orally administered cyclosporine A (CsA) in allogeneic hematopoietic stem cell transplant (HSCT) recipients. We included 118 allogeneic HSCT patients who received CsA and POS simultaneously between January 2017 and June 2020 in this study. The ratio of CsA blood concentration (ng/mL) to dosage (mg/day) (C/D) before and after POS initiation was compared. After the initiation of POS, the level of CsA increased 1 to 2 times in 66% (78/118) of patients compared to those without POS. However, the CsA C/D ratio increased by more than threefold in 6% (7/118) of patients after POS initiation, with an increase of more than fourfold in two patients. The median C/D ratio of CsA increased from 0.89 to 1.23 (P < 0.001) and 0.78 to 1.22 (P < 0.001) after POS initiation when CsA was administered intravenously and orally, respectively. In patients who received POS at the time of transition from intravenous to oral CsA, the value increased from 1.01 to 1.38 (P = 0.001). The route of administration had no significant effect on the change in the CsA C/D ratio (P = 0.615). Additionally, we observed the time required for the C/D ratio to reach a plateau after POS initiation was similar on days 13, 8, and 15 under various scenarios. POS treatment increased blood CsA levels. A large variability was found in the fold-change in the CsA C/D ratio. Therefore, CsA doses should be adjusted by closely monitoring the blood levels of CsA after POS initiation.

Drug-Drug Interactions With Cyclosporine in the Anti-Hepatitis C Viral PrOD Combination Regimen of Paritaprevir/Ritonavir-Ombitasvir and Dasabuvir in Organ Transplant Recipients With Severe Hepatic Fibrosis or Cirrhosis.

The clinical guidelines suggest that the dosing of cyclosporine (CsA), during combination therapy with paritaprevir/ritonavir-ombitasvir and dasabuvir (PrOD), would be only one-fifth of the pre-PrOD total daily dose to be administered once daily. However, this dosing may not be applicable to all patients depending on their clinical condition. This study focuses on the pharmacokinetic dynamics of PrOD with CsA in Asian organ transplant recipients with severe liver fibrosis or cirrhosis who undergo concurrent treatment with PrOD treatment and CsA. The efficacy and safety of PrOD treatment was also evaluated. Data from 7 patients obtained between January 2017 and September 2017 were retrospectively analyzed. Determinations of the blood concentrations of CsA were made, whether used as a single treatment or in combination therapy with PrOD. The combination regimen compared with CsA administered alone resulted in a 4.53-fold and 5.52-fold increase in the area under the concentration-time curve from time 0-12 hours (AUC0-12 h) of CsA on days 1 and 15, respectively. In addition, the maximal concentration, time to maximum concentration, and terminal phase elimination half-life (t1/2) of CsA were increased during the combined treatment of PrOD and CsA. The authors proposed reducing the CsA dosage during PrOD treatment to one-seventh of that of the pre-PrOD treatment of the total daily dose to maintain target CsA levels. All patients achieved sustained virologic responses at week 12. There were no episodes of serious adverse events or graft rejections observed. Although the combination with PrOD significantly affects the pharmacokinetics of CsA, it is effective and safe with regular monitoring of the CsA blood concentrations and appropriate CsA dose adjustment.

Sensitive, wide-range and high-throughput quantification of cyclosporine in whole blood using ultra-performance liquid chromatography coupled to tandem mass spectrometry and comparison with an antibody-conjugated magnetic immunoassay.

Because either trough or peak concentration at 2 h after administration is measured in routine therapeutic drug monitoring for cyclosporine A (CyA), a quantification method with a wide-range calibration curve capable of simultaneously measuring both concentrations is required. We developed a sensitive, wide-range and high-throughput quantification method for CyA in whole blood using ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS), and compared patients' blood CyA levels measured by UPLC-MS/MS and antibody-conjugated magnetic immunoassay (ACMIA). Whole blood samples were prepared by solid-phase extraction using Oasis HLB μElution plate. The UPLC-MS/MS assay showed excellent linearity over a wide calibration range of 5-2500 ng/mL. Within-batch accuracy and precision as well as batch-to-batch accuracy and precision fulfilled the criteria of US Food and Drug Administration guidelines. The blood CyA concentrations measured by the UPLC-MS/MS assay correlated strongly with those measured by ACMIA. A Bland-Altman plot showed a fixed error between CyA concentrations measured by the two methods, and the concentrations measured by the UPLC-MS/MS method were consistently lower than those measured by ACMIA. We have succeeded to develop a sensitive, wide-range and high-throughput quantification method for CyA in whole blood using UPLC-MS/MS.

Development of a Population Pharmacokinetic Model for Cyclosporine from Therapeutic Drug Monitoring Data.

Aim To develop a population pharmacokinetic model for Uruguayan patients under treatment with cyclosporine (CsA) that can be applied to TDM. Patients and Methods. A total of 53 patients under treatment with CsA were included. 37 patients with at least one pharmacokinetic profile described with four samples were considered for model building, while the remaining 16 were considered for the assessments of predictive performances. Pharmacokinetic parameter estimation was performed using a nonlinear mixed effect modelling implemented in the Monolix® software (version 2019R1, Lixoft, France); meanwhile, simulations were performed in R v.3.6.0 with the mlxR package. Results A two-compartment model with a first-order disposition model including lag time was used as a structural model. The final model was internally validated using prediction corrected visual predictive check (pcVPC) and other graphical diagnostics. A total of 621 CsA steady-state concentrations were analyzed for model development. Population estimates for the absorption constant (ka) and lag time were 0.523 h−1 and 0.512 h, respectively; apparent clearance (CL/F) was 30.3 L/h (relative standard error [RSE] ± 8.25%) with an interindividual variability of 39.8% and interoccasion variability of 38.0%; meanwhile, apparent clearance of distribution (Q/F) was 17.0 L/h (RSE ± 12.1%) with and interindividual variability of 53.2%. The covariate analysis identified creatinine clearance (ClCrea) as an individual factor influencing the Cl of CsA. The predictive capacity of the population model was demonstrated to be effective since predictions made for new patients were accurate for C1 and C2 (MPPEs below 50%). Bayesian forecasting improved significantly in the second and third occasions. Conclusion A population pharmacokinetic model was developed to reasonably estimate the individual cyclosporine clearance for patients. Hence, it can be utilized to individualize CsA doses for prompt and adequate achievement of target blood concentrations of CsA.

Comparison of sample preparation methods, validation of an UPLC–MS/MS procedure for the quantification of cyclosporine A in whole blood sample

Current main methods for therapeutic drug monitoring (TDM) of cyclosporine A (CsA) are immunoassays and liquid chromatography tandem mass spectrometry. The sample pretreatment of these methods is mainly based on extraction of drug which is bound to erythrocytes by divalent heavy metal ions (such as zinc and copper). Although these methods are effective for whole blood drug extraction and measurement, the pollution of heavy metals in sample pretreatment process will have potential negative impact on environment and human health. To overcome the pollution problem, in this study we have developed and validated an UPLC-MS/MS method for CsA determination in whole blood samples using physical pretreatment method. According to the characteristics of erythrocytes, a series of physical pretreatment methods, including sonication, freeze-thaw and osmotic burst, have been developed and evaluated. The results showed that the osmotic burst method was an effective way for drug extraction from erythrocytes. The lower limit of quantitation for CsA was 25 ng/mL, the within-run and between-run coefficient of variations were both less than 11.6 %. The agreement of the UPLC-MS/MS methods using these two sample pretreatment was evaluated by Bland-Altman plot and the two-tailed Student’s T-test. Comparison studies show that the effect of erythrocyte fragmentation by osmotic burst is similar to that of zinc sulfate method. The CsA measurement of 103 whole blood samples obtained by these two UPLC-MS/MS assays were no significant difference. These results demonstrate that the sample pretreatment by osmotic burst method is an eco-friendly and precise method for detecting the whole blood CsA concentration and therapeutic drug monitoring of CsA.

Diltiazem aggravates testicular function impairment induced by cyclosporine A or tacrolimus in unilateral nephrectomised rats.

The aim of this study was to elucidate the reproductive toxicity of the coadministration of diltiazem and cyclosporine A or tacrolimus. Testicular development, semen quality, sex hormones and testicular tissues were assessed in unilateral nephrectomised (UN) rats, including the control group, UN group, UN+CsA group, UN+FK506 group, UN+Rapa group, UN+CsA+Dil group and UN+FK506+Dil group. The testicular coefficient, the sperm number and the sperm motility were lower in the treatment groups (except UN+FK506) than in the control and UN groups (all p<0.05). The lowest sperm number and motility were identified in the UN+CsA+Dil group, followed by the UN+CsA group. The proportion of abnormal sperm was higher in the UN+CsA and UN+CsA+Dil groups than in the control and UN groups, respectively (p<0.05). The plasma concentrations of sex hormones were changed in the treatment groups. Dil can increase the blood concentrations of CsA and FK506 (◇p<0.05, ◆p<0.05). Therapeutic doses of these agents induced morphological changes in the testicular tissue and ultrastructural changes in the testosterone, mesenchymal cells and supporting cells. Our present study suggests that Dil can increase the testicular toxicity of CNIs (calcineurin inhibitors, including CsA and FK506) by enhancing the plasma concentrations of CNIs.

Eradication of Helicobacter pylori in a Living Donor Liver Transplant Recipient With Immunosuppressive Therapy of Cyclosporine A: A Case Report

A 54-year-old woman underwent living donor liver transplantation (LDLT) for primary biliary cholangitis (PBC) three years earlier. She took cyclosporine A (CyA) 150 mg/day as immunosuppression for prevention of rejection and PBC recurrence. Routine upper gastrointestinal endoscopy showed chronic atrophic gastritis and hyperplastic polyp, and rapid urease test was positive. Anti-Helicobacter pylori (H. pylori) serum IgG was elevated to 51 U/ml. We performed H. pylori eradication therapy with amoxicillin, clarithromycin and lansoprazole measuring the blood CyA concentration every day. Although the blood CyA concentration reached a peak (the concentration 2 hours after the administration: 818 ng/ml) on the second day, she did not develop renal dysfunction or other obvious adverse effects. Five weeks after the treatment, we confirmed eradication of H. pylori with the urea breath test. We herein reported a case of successful eradication of H. pylori in a LDLT recipient on immunosuppressive therapy with CyA without adverse effects.

Drug interactions and safety profiles with concomitant use of caspofungin and calcineurin inhibitors in allogeneic haematopoietic cell transplantation.

Small-scale clinical studies have reported on drug interactions between caspofungin (CPFG) and calcineurin inhibitors in healthy subjects; however, little is known about these interactions in allogeneic haematopoietic cell transplantation (allo-HCT) patients. We retrospectively assessed the drug interactions and safety profiles in allo-HCT recipients treated concomitantly with CPFG and calcineurin inhibitors. Ninety-one consecutive cases were evaluated. There were no statistically significant differences in the plasma concentration/dose (C/D) ratios of tacrolimus (TAC) in 34 patients before and after co-administration with CPFG (median: 575.6-672.4, P=0.200). In contrast, the median C/D ratio of cyclosporin A (CsA) in 16 patients was significantly elevated after co-administration with CPFG (median: 62.8-74.9, P=0.016). There were no serious adverse effects on liver or renal function associated with the therapy. Our data show that CPFG did not affect the pharmacokinetics of TAC and that it could mildly increase CsA blood concentrations in allo-HCT patients.

Analytical performance evaluation of the Elecsys® Cyclosporine and Elecsys® Tacrolimus assays on the cobas e411 analyzer

BackgroundCyclosporine (CsA) and tacrolimus (TAC) are immunosuppressant drugs that are often used to treat autoimmune diseases and as transplantation therapy; therefore, their concentrations need to be monitored carefully. We herein evaluated the analytical performance of the Elecsys® Cyclosporine and Elecsys® Tacrolimus assay kits, which have been newly developed to measure CsA and TAC concentrations in the whole blood. MethodsWe used residual whole blood samples from autoimmune disease and transplantation patients who were being treated with CsA or TAC. CsA concentrations were measured using an affinity chrome-mediated immunoassay (ACMIA) and an electrochemiluminescence immunoassay (ECLIA). TAC concentrations were measured using a chemiluminescence immunoassay (CLIA) and ECLIA. We investigated assay precision, linearity, lower limit of quantitation (LOQ), stability of calibration, influence of interference substances and the hematocrit, correlation of ACMIA with ECLIA, and correlation of CLIA with ECLIA. ResultsWithin-assay coefficients of variation were 1.8−3.6% (CsA: 94−1238 ng/mL) and 2.9−3.9% (TAC: 2.1−17.8 ng/mL), whereas day-to-day coefficients of variation ranged between 3.0−4.1% (CsA) and 2.8−3.9% (TAC). The limits of quantitation were defined as the concentration at which the CV was approximately 10%. Each lower LOQ obtained was 16 ng/mL (CsA), and 0.95 ng/mL (TAC). CsA and TAC calibrations were stable for at least 21 days. Neither the presence of conjugated bilirubin, unconjugated bilirubin, chyle, and rheumatoid factor nor the hematocrit affected these assays. A method comparison using a standardized major axis regression analysis of ACMIA and ECLIA was r=0.995, y=0.924x −1.175, n=200 (CsA), while that of CLIA and ECLIA was r=0.994, y=1.080x −0.197, n=200 (TAC). ConclusionsThe analytical performances of the Elecsys® Cyclosporine and Elecsys®Tacrolimus assays were acceptable. Furthermore, CyA and TAC concentrations may be simultaneously measured using a single pretreatment which is of benefit if patients have to undertake conversion between these two drugs. Additionally, it benefits the workflow in the clinical laboratory. Thus, the Elecsys® Cyclosporine and Elecsys® Tacrolimus assays may be suitable for routine therapeutic drug monitoring.

Evaluation of the Interaction of Intravenous and Oral Voriconazole with Oral Cyclosporine in Iranian HSCT Patients.

Objective:Voriconazole as a triazole antifungal agent is widely used for prophylaxis or treatment of fungal infections in allogeneic hematopoietic stem cell transplantation (HSCT). It can increase blood concentrations of other medications including cyclosporine A (CsA) which are substrates for cytochrome P450 3A4. The aim of this study was to evaluate comparatively the interaction between oral/intravenous (IV) voriconazole and oral CsA.Methods:Twenty-nine recipients of allogeneic HSCT who had been already on a steady dose of CsA and were started on oral or IV voriconazole were evaluated in a prospective cohort study. Blood concentration of CsA was determined before and 5–8 days after voriconazole initiation. Plasma concentration of voriconazole was measured in steady state. The changes in blood concentration of CsA after administration of voriconazole were evaluated.Findings:The concentration/dose (C/D) ratio of CsA increased significantly (P < 0.001) after voriconazole initiation in both routes of administration (8.40%–174.10% increase in C/D ratio). The C/D ratio alteration of CsA did not differ significantly between oral and IV voriconazole group (P = 0.405). There was a significant correlation in all patients between plasma concentration of voriconazole and percentage of CsA C/D ratio increment (P = 0.046).Conclusion:There was a significant intrapatient variability in the magnitude of CsA blood concentration increment after voriconazole initiation. We also demonstrated that magnitude of drug interaction did not differ in IV and oral voriconazole administration. Furthermore, we found that the magnitude of drug interaction was correlated with plasma concentration of voriconazole.

Could salivary cyclosporine dosage replace the whole blood cyclosporine measurements in renal transplant patients?

Background:Cyclosporin (CsA) has been extensively used as the immunosuppressant of choice in renal transplantation. Currently available approaches to assess CsA levels, both in serum and blood, fail to accurately reflect the concentration of the pharmacologically active drug fraction. Free CsA levels in biological fluids (blood or saliva) have been advocated to play an important role. Traditional salivary CsA monitoring tests are based on available archaic salivary techniques that are nonspecific and require large amounts of saliva. The aim of this study was to assess salivary CsA correlation using a novel and more accurate technique and to correlate with CsA levels in blood.Material and Methods: Patients provided blood samples of 2 ml and 2 ml of unstimulated saliva on the same day 2 h after the morning CsA dose (C2). Whole blood levels of CsA were determined using the monoclonal fluorescent polarization immunoassay (FPIA) kit. The FPIA kit was adapted to salivary testing by using a novel extraction method developed and patented under the name of Middle East Research Institute (MERI). Wilcoxon signed rank test compared the differences in blood and salivary CsA. Pearson's correlation coefficient assessed the linear association between blood and salivary CsA concentrations. All analyses were performed using IBM-SPSS version 23 (IBM Corp, Armonk, NY, USA).Results: No significant correlation was observed between blood and salivary CsA levels.Conclusion: Salivary CsA concentrations at C2 cannot adequately replace C2 blood levels as an indicator of CsA bioavailability despite improved performance of monoclonal FPIA and application of the MERI technique. More studies may be warranted to design more reliable and less invasive procedures for therapeutic drug monitoring.

Diltiazem co treatment with cyclosporine for induction of disease remission in sight-threatening non-infectious intraocular inflammation.

To investigate the effects of diltiazem co-treatment with microemulsified cyclosporine-A (CsA) on dosage, blood concentrations of CsA, as well as therapeutic and side effects in patients with sight-threatening non-infectious intraocular inflammation. A prospective, randomized, placebo-controlled, open-label trial of 39 patients with sight-threatening non-infectious intraocular inflammation. The change in visual acuity (LogMAR), the grade of inflammatory activity, therapeutic concentration of CsA in the blood and systemic and renal toxicity were determined after comparing two groups, one treated with CsA and diltiazem (treatment group), and the other without diltiazem (control group). Compared with the control group, the concentration of CsA in the blood of the treatment group significantly increased (P<0.05) requiring a reduction in dosage of CsA (P<0.05). In patients with severe intraocular inflammation treated with CsA and diltiazem, blood concentrations of CsA increased as the dosage decreased. This efficient combination therapy reduced patient's economic burden, at the same time decreasing systemic and renal toxicity which in turn may promote the use of CsA for longer periods.

Blood concentration of cyclosporine during early post-transplant period may have influence on the occurrence of chronic graft versus host disease in patients who received allogeneic hematopoietic stem cell transplantation.

IntroductionIt has rarely been studied that how the blood level of CsA affect the incidence of chronic GVHD after allogeneic hematopoietic stem cell transplantation (allo-HSCT).MethodsA total of 183 patients who underwent allo-HSCT from an HLA-matched or haplo matched family donors between 2006 and 2014 were reviewed.ResultsThe average monthly CsA blood concentration (CsAavr, ng/ml) was calculated in each patient: 0-1, 1-2, and 2-3 months after allo-HSCT. CsAavr at the first month showed significant association with the occurrence of moderate to severe cGVHD in multivariate analysis adjusted for gender, age, total body irradiation, anti-thymocyte globulin, acute GVHD ≥ grade 2 and CsAavr levels of other periods. The risk of cGVHD development was lowest in patients with CsAavr of 200-250 ng/ml when compared to those with CsAavr of ≥ 250 or < 200 ng/ml (p=0.003).ConclusionsCsA level between 200 and 250 mg/ml during the first month after transplantation was significantly associated with the decreased risk of moderate to severe cGVHD.

Sustained-release of Cyclosporin A pellets: preparation, in vitro release, pharmacokinetic studies and in vitro–in vivo correlation in beagle dogs

The aim of this study was to develop Cyclosporin A (CsA) sustained-release pellets which could maintain CsA blood concentration within the therapeutic window throughout dosing interval and to investigate the in vitro–in vivo correlation (IVIVC) in beagle dogs. The CsA sustained-release pellets (CsA pellets) were prepared by a double coating method and characterized in vitro as well as in vivo. Consequently, the CsA pellets obtained were spherical in shape, with a desirable drug loading (7.18 ± 0.17 g/100 g), good stability and showed a sustained-release effect. The Cmax, Tmax and AUC0–24 of CsA pellets from the in vivo pharmacokinetics evaluation was 268.22 ± 15.99 ng/ml, 6 ± 0 h and 3205.00 ± 149.55 ng·h/ml, respectively. Compared with Neoral®, CsA pellets significantly prolonged the duration of action, reduced the peak blood concentration and could maintain a relatively high concentration level till 24 h. The relative bioavailability of CsA pellets was 125.68 ± 5.37% that of Neoral®. Moreover, there was a good correlation between the in vitro dissolution and in vivo absorption of the pellets. In conclusion, CsA pellets which could ensure a constant systemic blood concentration within the therapeutic window for 24 h were prepared successfully. Meanwhile, this formulation possessed a good IVIVC.