scholarly journals Software for Dosage Individualization of Voriconazole for Immunocompromised Patients

2013 ◽  
Vol 57 (4) ◽  
pp. 1888-1894 ◽  
Author(s):  
William W. Hope ◽  
Michael VanGuilder ◽  
J. Peter Donnelly ◽  
Nicole M. A. Blijlevens ◽  
Roger J. M. Brüggemann ◽  
...  
Keyword(s):  
Therapeutic Drug Monitoring ◽  
Drug Monitoring ◽  
Fungal Infections ◽  
Plasma Concentrations ◽  
Therapeutic Drug ◽  
Cell Transplant ◽  
Multiple Model ◽  
Pharmacokinetic Variability ◽  
Hematopoietic Stem ◽  
Wide Range

ABSTRACTThe efficacy of voriconazole is potentially compromised by considerable pharmacokinetic variability. There are increasing insights into voriconazole concentrations that are safe and effective for treatment of invasive fungal infections. Therapeutic drug monitoring is increasingly advocated. Software to aid in the individualization of dosing would be an extremely useful clinical tool. We developed software to enable the individualization of voriconazole dosing to attain predefined serum concentration targets. The process of individualized voriconazole therapy was based on concepts of Bayesian stochastic adaptive control. Multiple-model dosage design with feedback control was used to calculate dosages that achieved desired concentration targets with maximum precision. The performance of the software program was assessed using the data from 10 recipients of an allogeneic hematopoietic stem cell transplant (HSCT) receiving intravenous (i.v.) voriconazole. The program was able to model the plasma concentrations with a high level of precision, despite the wide range of concentration trajectories and interindividual pharmacokinetic variability. The voriconazole concentrations predicted after the last dosages were largely concordant with those actually measured. Simulations provided an illustration of the way in which the software can be used to adjust dosages of patients falling outside desired concentration targets. This software appears to be an extremely useful tool to further optimize voriconazole therapy and aid in therapeutic drug monitoring. Further prospective studies are now required to define the utility of the controller in daily clinical practice.

scholarly journals 1733. Voriconazole Prophylaxis Following Allogeneic Hematopoietic Stem Cell Transplant: How Much Is Enough, Are Low Voriconazole Levels Associated With Opportunistic Infections, and What Are the Reasons for Discontinuation?

2019 ◽  
Vol 6 (Supplement_2) ◽  
pp. S635-S635
Author(s):  
Giorgos Hadjivassiliou ◽  
Claire Rummage ◽  
Craig Hoesley ◽  
Matthew L Brown
Keyword(s):  
Stem Cell ◽  
Therapeutic Drug Monitoring ◽  
Hematopoietic Stem Cell ◽  
Drug Monitoring ◽  
Fungal Infections ◽  
Invasive Fungal Infections ◽  
Therapeutic Drug ◽  
Cell Transplant ◽  
Hematopoietic Stem ◽  
Subtherapeutic Level

Abstract Background Patients who undergo allogeneic hematopoietic stem cell transplantation (alloHSCT) are at increased risk for invasive fungal infections with associated high morbidity and mortality that necessitates the use of prophylactic antifungals. Voriconazole is commonly used for prophylaxis, but there are no recommendations for therapeutic drug monitoring. The purpose of this study was to characterize voriconazole therapeutic drug monitoring and associated outcomes in this patient population. Methods AlloHSCT patients receiving voriconazole prophylaxis at the University of Alabama at Birmingham Hospital between March 2015 and March 2018 were included in the analysis. Serum voriconazole levels (SVL) were evaluated to determine what percentage of patients achieved prophylactic or therapeutic concentrations. Incidence of invasive fungal infections (IFI) and voriconazole discontinuation was also assessed. Results Voriconazole prophylaxis was used in 151 of 162 alloHSCT patients, and 120 patients (79%) had SVL drawn correctly (≥4 days after initiation of course). We found that 35 (29%) patients achieved a subtherapeutic level (<0.5 μg/mL), 17 (14%) prophylactic level (0.5 to 1 μg/mL), 68 (57%) therapeutic level (1 to 5.5 μg/mL), and no patients achieved a supratherapeutic level (level ≥5.5 μg/mL). Voriconazole prophylaxis was discontinued early in 60 of 151 patients. Most common etiologies for discontinuation included liver function test abnormalities (44%) and encephalopathy (21%). The average SVL was 1.2 μg/mL in those requiring discontinuation. Four patients (3%) developed an IFI while receiving prophylactic voriconazole, of which only 1 had subtherapeutic level. Conclusion Even though approximately one-third of patients achieved a subtherapeutic SVL, there was no correlation with breakthrough IFI. There was also no linear correlation between SVL and risk of adverse effects requiring discontinuation. Our observational data do not support a need for therapeutic drug monitoring in alloHSCT patients receiving prophylactic voriconazole. Disclosures All authors: No reported disclosures.

scholarly journals Recent Advances in Therapeutic Drug Monitoring of Voriconazole, Mycophenolic Acid, and Vancomycin: A Literature Review of Pediatric Studies

Pharmaceutics ◽  
2021 ◽  
Vol 13 (12) ◽  
pp. 1991
Author(s):  
Matylda Resztak ◽  
Joanna Sobiak ◽  
Andrzej Czyrski
Keyword(s):  
Therapeutic Drug Monitoring ◽  
Mycophenolic Acid ◽  
Drug Monitoring ◽  
Pediatric Patients ◽  
Fungal Infections ◽  
Cord Blood Transplantation ◽  
Active Form ◽  
Therapeutic Drug ◽  
Hematopoietic Stem ◽  
Acute Kidney Disease

The review includes studies dated 2011–2021 presenting the newest information on voriconazole (VCZ), mycophenolic acid (MPA), and vancomycin (VAN) therapeutic drug monitoring (TDM) in children. The need of TDM in pediatric patients has been emphasized by providing the information on the differences in the drugs pharmacokinetics. TDM of VCZ should be mandatory for all pediatric patients with invasive fungal infections (IFIs). Wide inter- and intrapatient variability in VCZ pharmacokinetics cause achieving and maintaining therapeutic concentration during therapy challenging in this population. Demonstrated studies showed, in most cases, VCZ plasma concentrations to be subtherapeutic, despite the updated dosages recommendations. Only repeated TDM can predict drug exposure and individualizing dosing in antifungal therapy in children. In children treated with mycophenolate mofetil (MMF), similarly as in adult patients, the role of TDM for MMF active form, MPA, has not been well established and is undergoing continued debate. Studies on the MPA TDM have been carried out in children after renal transplantation, other organ transplantation such as heart, liver, or intestine, in children after hematopoietic stem cell transplantation or cord blood transplantation, and in children with lupus, nephrotic syndrome, Henoch-Schönlein purpura, and other autoimmune diseases. MPA TDM is based on the area under the concentration–time curve; however, the proposed values differ according to the treatment indication, and other approaches such as pharmacodynamic and pharmacogenetic biomarkers have been proposed. VAN is a bactericidal agent that requires TDM to prevent an acute kidney disease. The particular group of patients is the pediatric one. For this group, the general recommendations of the dosing may not be valid due to the change of the elimination rate and volume of distribution between the subjects. The other factor is the variability among patients that concerns the free fraction of the drug. It may be caused by both the patients’ population and sample preconditioning. Although VCZ, MMF, and VAN have been applied in pediatric patients for many years, there are still few issues to be solve regarding TDM of these drugs to ensure safe and effective treatment. Except for pharmacokinetic approach, pharmacodynamics and pharmacogenetics have been more often proposed for TDM.

scholarly journals Multicenter Study of Posaconazole Therapeutic Drug Monitoring: Exposure-Response Relationship and Factors Affecting Concentration

2012 ◽  
Vol 56 (11) ◽  
pp. 5503-5510 ◽  
Author(s):  
Michael J. Dolton ◽  
John E. Ray ◽  
Sharon C.-A. Chen ◽  
Kingsley Ng ◽  
Lisa Pont ◽  
...  
Keyword(s):  
Therapeutic Drug Monitoring ◽  
Drug Interactions ◽  
Fungal Infection ◽  
Drug Monitoring ◽  
Linear Regression Analysis ◽  
Therapeutic Drug ◽  
Cell Transplant ◽  
Clinical Factors ◽  
Hematopoietic Stem ◽  
Exposure Response

ABSTRACTPosaconazole has an important role in the prophylaxis and salvage treatment of invasive fungal infections (IFIs), although poor and variable bioavailability remains an important clinical concern. Therapeutic drug monitoring of posaconazole concentrations has remained contentious, with the use of relatively small patient cohorts in previous studies hindering the assessment of exposure-response relationships. This multicenter retrospective study aimed to investigate relationships between posaconazole concentration and clinical outcomes and adverse events and to assess clinical factors and drug interactions that may affect posaconazole concentrations. Medical records were reviewed for patients who received posaconazole and had ≥1 concentration measured at six hospitals in Australia. Data from 86 patients with 541 posaconazole concentrations were included in the study. Among 72 patients taking posaconazole for prophylaxis against IFIs, 12 patients (17%) developed a breakthrough fungal infection; median posaconazole concentrations were significantly lower than in those who did not develop fungal infection (median [range], 289 [50 to 471] ng/ml versus 485 [0 to 2,035] ng/ml;P< 0.01). The median posaconazole concentration was a significant predictor of breakthrough fungal infection via binary logistic regression (P< 0.05). A multiple linear regression analysis identified a number of significant drug interactions associated with reduced posaconazole exposure, including coadministration with proton pump inhibitors, metoclopramide, phenytoin or rifampin, and the H2antagonist ranitidine (P< 0.01). Clinical factors such as mucositis, diarrhea, and the early posttransplant period in hematopoietic stem cell transplant recipients were also associated with reduced posaconazole exposure (P< 0.01). Low posaconazole concentrations are common and are associated with breakthrough fungal infection, supporting the utility of monitoring posaconazole concentrations to ensure optimal systemic exposure.

scholarly journals Posaconazole Exposure-Response Relationship: Evaluating the Utility of Therapeutic Drug Monitoring

2012 ◽  
Vol 56 (6) ◽  
pp. 2806-2813 ◽  
Author(s):  
Michael J. Dolton ◽  
John E. Ray ◽  
Deborah Marriott ◽  
Andrew J. McLachlan
Keyword(s):  
Therapeutic Drug Monitoring ◽  
Drug Monitoring ◽  
Fungal Infections ◽  
Gastrointestinal Disease ◽  
Plasma Concentrations ◽  
Response To Therapy ◽  
Common Finding ◽  
Therapeutic Drug ◽  
Response Relationship ◽  
Exposure Response

ABSTRACTPosaconazole has become an important part of the antifungal armamentarium in the prophylaxis and salvage treatment of invasive fungal infections (IFIs). Structurally related to itraconazole, posaconazole displays low oral bioavailability due to poor solubility, with significant drug interactions and gastrointestinal disease also contributing to the generally low posaconazole plasma concentrations observed in patients. While therapeutic drug monitoring (TDM) of plasma concentrations is widely accepted for other triazole antifungal agents such as voriconazole, the utility of TDM for posaconazole is controversial due to debate over the relationship between posaconazole exposure in plasma and clinical response to therapy. This review examines the available evidence for a relationship between plasma concentration and clinical efficacy for posaconazole, as well as evaluating the utility of TDM and providing provisional target concentrations for posaconazole therapy. Increasing evidence supports an exposure-response relationship for plasma posaconazole concentrations for prophylaxis and treatment of IFIs; a clear relationship has not been identified between posaconazole concentration and toxicity. Intracellular and intrapulmonary concentrations have been studied for posaconazole but have not been correlated to clinical outcomes. In view of the high mortality and cost associated with the treatment of IFIs, increasing evidence of an exposure-response relationship for posaconazole efficacy in the prevention and treatment of IFIs, and the common finding of low posaconazole concentrations in patients, TDM for posaconazole is likely to be of significant clinical utility. In patients with subtherapeutic posaconazole concentrations, increased dose frequency, administration with high-fat meals, and withdrawal of interacting medications from therapy are useful strategies to improve systemic absorption.

Clinical considerations on posaconazole administration and therapeutic drug monitoring in allogeneic hematopoietic cell transplant recipients

2020 ◽  
Author(s):  
Mateja Kraljevic ◽  
Nina Khanna ◽  
Michael Medinger ◽  
Jakob Passweg ◽  
Stavroula Masouridi-Levrat ◽  
...  
Keyword(s):  
Therapeutic Drug Monitoring ◽  
Drug Monitoring ◽  
Fungal Infections ◽  
Primary Objective ◽  
Hematopoietic Cell ◽  
Therapeutic Drug ◽  
Cell Transplant ◽  
Transplant Recipients ◽  
Hematopoietic Cell Transplant ◽  
Allogeneic Hematopoietic Cell Transplant

Abstract There is a paucity of data on posaconazole (PCZ) dosing and therapeutic-drug-monitoring (TDM) in allogeneic hematopoietic cell transplant recipients (allogeneic-HCTr). This was a 3-year retrospective multicenter study (January 1, 2016 to December 31, 2018) in adult allogeneic-HCTr who received PCZ (intravenously, IV and/or as delayed-release tablet, DRT) as prophylaxis or treatment for ≥7 consecutive days (D) with at least 1-PCZ-level available using data of the Swiss Transplant Cohort Study. The primary objective was to describe the distribution of PCZ-level and identify predictors of therapeutic PCZ-level and associations between PCZ-dosing and PCZ-level. A total of 288 patients were included: 194 (67.4%) and 94 (32.6%) received PCZ as prophylaxis and treatment, respectively, for a median of 90 days (interquartile range, IQR: 42–188.5). There were 1944 PCZ-level measurements performed, with a median PCZ level of 1.3 mg/L (IQR: 0.8-1.96). PCZ-level was &lt;0.7 mg/L in 383/1944 (19.7%) and &lt;1.0 mg/L in 656/1944 (33.7%) samples. PCZ-level was &lt;0.7 mg/L in 260/1317 (19.7%) and &lt;1.0 mg/L in 197/627 (31.4%) in patients who received PCZ-prophylaxis versus treatment, respectively. There were no significant differences in liver function tests between baseline and end-of-treatment. There were nine (3.1%) breakthrough invasive fungal infections (bIFI), with no difference in PCZ levels between patients with or without bIFI. Despite a very intensive PCZ-TDM, PCZ-levels remain below target levels in up to one-third of allogeneic-HCTr. Considering the low incidence of bIFI observed among patients with PCZ levels in the targeted range, our data challenge the clinical utility of routine universal PCZ-TDM.

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