Future Studies on the Interaction Between Clozapine and Valproic Acid Should Aspire to Include Longitudinal Designs and Free Valproate Concentrations, and Should Consider that Inducer and/or Inhibitory Effects May Vary With Time, the Individual, and the Auto-Induction of Valproic Acid
No abstract available (Source: Therapeutic Drug Monitoring)
Source: Therapeutic Drug Monitoring - January 14, 2020 Category: Drugs & Pharmacology Tags: Letters to the Editor Source Type: research

Clinical Applications of Physiologically Based Pharmacokinetic Modeling: Perspectives on the Advantages and Challenges
No abstract available (Source: Therapeutic Drug Monitoring)
Source: Therapeutic Drug Monitoring - January 14, 2020 Category: Drugs & Pharmacology Tags: Letters to the Editor Source Type: research

Δ9-Tetrahydrocannabinol and Cannabidiol Time Courses in the Sera of “Light Cannabis” Smokers: Discriminating Light Cannabis Use from Illegal and Medical Cannabis Use
Conclusions: THC and CBD time courses in the sera of light cannabis smokers were similar to those previously observed in oral fluid and blood. Serum THC/CBD concentration ratio not higher than the mean value of 0.9 might be a useful biomarker to identify use of light cannabis versus that of illegal THC cannabis (where THC/CBD concentration ratios are generally greater than 10) or versus that of medical cannabis (where ratios are greater than 1). Consumers should be advised of possible drowsiness after he repeated smoking of light cannabis cigarettes. (Source: Therapeutic Drug Monitoring)
Source: Therapeutic Drug Monitoring - January 14, 2020 Category: Drugs & Pharmacology Tags: Short Communication Source Type: research

Simple and Rapid Quantification of the Multi-Enzyme Targeting Antifolate Pemetrexed in Human Plasma
Background: Pemetrexed is an antifolate cytostatic drug that targets multiple enzymes involved in folate biosynthesis and is indicated for treatment of non–small-cell lung cancer and malignant pleural mesothelioma. As evidence for an exposure–response/toxicity relationship is accumulating, dose individualization using therapeutic drug monitoring may be a feasible strategy to optimize treatment. The purpose of this study was to develop a simple, sensitive, high-performance liquid chromatography method with UV detection for quantification of pemetrexed levels in human plasma. Method: The method involves a si...
Source: Therapeutic Drug Monitoring - January 14, 2020 Category: Drugs & Pharmacology Tags: Short Communication Source Type: research

Prospective Investigation of the Performance of 2 Gamma-Hydroxybutyric Acid Tests: DrugCheck GHB Single Test and Viva-E GHB Immunoassay
Conclusions: The DrugCheck GHB Single Test's specificity was sufficient, whereas its sensitivity was poor, making it unsuitable for use at point-of-care. Contrarily, using 50 mcg/mL as the cutoff value and excluding samples with ethanol levels ≥2.0 g/L, the Viva-E GHB immunoassay showed acceptable results to detect clinically relevant GHB intoxications. (Source: Therapeutic Drug Monitoring)
Source: Therapeutic Drug Monitoring - January 14, 2020 Category: Drugs & Pharmacology Tags: Original Article Source Type: research

Increased Arbekacin Clearance in Patients With Febrile Neutropenia
Background: Arbekacin (ABK) is used to treat infections caused by methicillin-resistant Staphylococcus aureus and is used widely for the treatment of febrile neutropenia (FN). As ABK has a narrow therapeutic concentration window, the dosage must be adjusted via therapeutic drug monitoring. However, the influence of the physiology of patients with FN on the pharmacokinetic (PK) parameters of ABK remains unclear. Therefore, we examined this influence on ABK PK parameters. Method: We performed a retrospective cohort study using data from patients with a hematologic malignancy who were ≥18 years and had been administer...
Source: Therapeutic Drug Monitoring - January 14, 2020 Category: Drugs & Pharmacology Tags: Original Article Source Type: research

Meropenem, Cefepime, and Piperacillin Protein Binding in Patient Samples
Conclusions: The average fu values were lower than those reported in the literature. There was also a large variability in fu; hence, it should be considered when managing patients administered with these drugs through direct measurements of free drug concentrations. (Source: Therapeutic Drug Monitoring)
Source: Therapeutic Drug Monitoring - January 14, 2020 Category: Drugs & Pharmacology Tags: Original Article Source Type: research

A Sensitive LC-MS/MS Assay for the Quantification of Methadone and its Metabolites in Dried Blood Spots: Comparison With Plasma
Introduction: Methadone, a synthetic narcotic, is widely used both in adults and children for pain control and as a replacement drug in opioid use disorder to prevent craving and withdrawal. To support clinical pharmacokinetic trials in neonates, infants, and children, the authors developed and validated a novel, automated, highly sensitive liquid chromatography–electrospray–tandem mass spectrometry ionization (LC-ESI-MS/MS) method for the quantification of methadone and its metabolites, 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine (EDDP) and 2-ethyl-5-methyl-3,3-diphenylpyraline (EMDP), in samples colle...
Source: Therapeutic Drug Monitoring - January 14, 2020 Category: Drugs & Pharmacology Tags: Original Article Source Type: research

Comparing Dried Blood Spots and Plasma Concentrations for Busulfan Therapeutic Drug Monitoring in Children
This study evaluated the feasibility of using the DBS method for Bu TDM. The hematocrit (Hct) and conditioning day were also examined for their impact on the DBS method's performance. Methods: Venous blood collected from 6 healthy volunteers was diluted, using their plasma into 4 samples of varying Hct values. Each sample was spiked with Bu calibrators (300, 600, and 1400 ng/mL), prepared using DBS and dried plasma spot (DPS) sampling and analyzed using a validated liquid-chromatography tandem-mass spectrometry method. Clinical blood samples (n = 153) from pediatric patients (n = 15) treated with Bu (mainly from doses 1...
Source: Therapeutic Drug Monitoring - January 14, 2020 Category: Drugs & Pharmacology Tags: Original Article Source Type: research

Predictors of Infliximab Trough Concentrations in Inflammatory Bowel Disease Patients Using a Repeated-Measures Design
Conclusions: In this repeated-measures study in a population of IBD patients, we observed significant associations between ATI, serum albumin concentration, concomitant immunosuppressive therapy, body weight and gender, and IFX Cmin, and CL. The high PK variability observed in this study supports the need for proactive TDM to optimize the use of IFX as early as possible in IBD patients. (Source: Therapeutic Drug Monitoring)
Source: Therapeutic Drug Monitoring - January 14, 2020 Category: Drugs & Pharmacology Tags: Original Article Source Type: research

Using Therapeutic Drug Monitoring and Pharmacovigilance to Overcome Some of the Challenges of Developing Medicinal Cannabis from Botanical Origins
Conclusions: A surge of public and clinical interest in the possible therapeutic applications of constituent cannabinoids has potentiated global legislative and policy reform. However, our understanding of its properties, optimized use, and harmful effects remains incomplete (Therapeutic Goods Administration. Guidance for the use of medicinal cannabis in Australia In: Department of Health Department, editor. Woden ACT Australian Government 2017; Dryburgh LM, Bolan NS, Grof CP, Galettis P, Schneider J, Lucas CJ, et al. Cannabis contaminants: sources, distribution, human toxicity and pharmacologic effects. Brit J Clin Phar...
Source: Therapeutic Drug Monitoring - January 14, 2020 Category: Drugs & Pharmacology Tags: Review Article Source Type: research

Current Situation of the Metabolomics Techniques Used for the Metabolism Studies of New Psychoactive Substances
Conclusions: Thus, there may be a certain potential for using metabolomics techniques in the field of NPS research, but a great challenge remains to thoroughly adopt the existing metabolomics methods. (Source: Therapeutic Drug Monitoring)
Source: Therapeutic Drug Monitoring - January 14, 2020 Category: Drugs & Pharmacology Tags: Review Article Source Type: research

Therapeutic Drug Monitoring Can Improve Linezolid Dosing Regimens in Current Clinical Practice: A Review of Linezolid Pharmacokinetics and Pharmacodynamics
Abstract: Linezolid is an antibiotic used to treat infections caused by drug-resistant gram-positive organisms, including vancomycin-resistant Enterococcus faecium, multi-drug resistant Streptococcus pneumoniae, and methicillin-resistant Staphylococcus aureus. The adverse effects of linezolid can include thrombocytopenia and neuropathy, which are more prevalent with higher exposures and longer treatment durations. Although linezolid is traditionally administered at a standard 600 mg dose every 12 hours, the resulting exposure can vary greatly between patients and can lead to treatment failure or toxicity. The efficacy an...
Source: Therapeutic Drug Monitoring - January 14, 2020 Category: Drugs & Pharmacology Tags: Review Article Source Type: research

Synthetic Cathinones and Their Potential Interactions with Prescription Drugs
Conclusions: Clinicians should be aware of possible interactions between synthetic cathinones and prescription drugs, which may increase the risk of drug toxicity or reduce the therapeutic efficacy of the drugs. Qualitative drug screening for cathinones using mass spectrometry methods may aid the early detection of these agents. (Source: Therapeutic Drug Monitoring)
Source: Therapeutic Drug Monitoring - January 14, 2020 Category: Drugs & Pharmacology Tags: Review Article Source Type: research

Impact of Therapeutic Drug Monitoring of Antiretroviral Drugs in Routine Clinical Management of People Living With HIV: A Narrative Review
Conclusions: The transformation of HIV infection from a near-universally fatal illness to a lifelong chronic disease has resulted in an HIV population that is growing and aging, placing new and increasing demands on public programs and health services. Increasingly, the management of comorbidities, polypharmacy, and drug–drug interaction, and their impact on antiretroviral therapy will have to be undertaken. These clinical settings represent some of the new frontiers for the use of TDM with the goal of achieving optimal prescription and outcome for PLWH. (Source: Therapeutic Drug Monitoring)
Source: Therapeutic Drug Monitoring - January 14, 2020 Category: Drugs & Pharmacology Tags: Review Article Source Type: research

Key Features Defining the Disposition of Bispecific Antibodies and Their Efficacy In Vivo
This study summarizes several PK and PD aspects that are specific for BsAbs and are important for the success of these new drugs. We emphasize previous PK/PD studies that have been fundamental for the correct prediction of appropriate dosages and schedules of these new drugs in clinical trials or for defining which drugs may take advantage of individualized and standardized drug monitoring for improved efficacy and safety. (Source: Therapeutic Drug Monitoring)
Source: Therapeutic Drug Monitoring - January 14, 2020 Category: Drugs & Pharmacology Tags: Review Article Source Type: research

Monoclonal Antibody Monitoring: Clinically Relevant Aspects, A Systematic Critical Review
Abstract: Monoclonal antibody (mAb) therapy does not usually lead to a clinical response in all patients and resistance may increase over time after repeated mAb administration. This lack or loss of response to the treatment may originate from different and little-known epigenetic, biomolecular, or pathophysiological mechanisms, although an inadequate serum concentration is perhaps the most likely cause, even if not widely recognized and investigated yet. Patient factors that influence the pharmacokinetics (PK) of a mAb should be taken into account. Multiple analyses of patient-derived PK data have identified various fac...
Source: Therapeutic Drug Monitoring - January 14, 2020 Category: Drugs & Pharmacology Tags: Review Article Source Type: research

Therapeutic Drug Monitoring of Targeted Anticancer Protein Kinase Inhibitors in Routine Clinical Use: A Critical Review
Conclusions: Adaptation of PKIs dosage regimens at the individual patient level, through a rational TDM approach, could prevent oncology patients from being exposed to ineffective or unnecessarily toxic drug concentrations in the era of personalized medicine. (Source: Therapeutic Drug Monitoring)
Source: Therapeutic Drug Monitoring - January 14, 2020 Category: Drugs & Pharmacology Tags: Focus Series: TDM in Oncology Source Type: research

Therapeutic Drug Monitoring of Sunitinib in Gastrointestinal Stromal Tumors and Metastatic Renal Cell Carcinoma in Adults—A Review
Conclusions: According to the current evidence presented in this review, a TDM-guided dose modification of sunitinib in selected groups of patients could provide a better treatment outcome while simultaneously preventing sunitinib toxicity. (Source: Therapeutic Drug Monitoring)
Source: Therapeutic Drug Monitoring - January 14, 2020 Category: Drugs & Pharmacology Tags: Focus Series: TDM in Oncology Source Type: research

Cancer Chemotherapy: The Case for Therapeutic Drug Monitoring
Abstract: The selection of an appropriate therapy and dosing regimen is a significant challenge in the treatment of cancer. Although there are recommended standardized chemotherapy protocols for some types of cancer, protocol changes that usually only occur after large clinical trials demonstrate improvements and individual patients often require dose modifications (amount or interval) or delays in dose administration as toxicities arise. In other areas of medicine, therapeutic drug monitoring is commonly and successfully used to ensure appropriate drug exposure and to limit dose-related toxicities. Currently, the wide p...
Source: Therapeutic Drug Monitoring - January 14, 2020 Category: Drugs & Pharmacology Tags: Focus Series: TDM in Oncology Source Type: research

Utility of Physiologically Based Pharmacokinetic Modeling in Point-of-Care Decisions: An Example Using Digoxin Dosing in Continuous Venovenous Hemodiafiltration
We describe the case of a patient on continuous venovenous hemodiafiltration with atrial fibrillation with rapid ventricular response and hypotension requiring vasopressor use, which warranted digoxin therapy. In the absence of guidelines specifying appropriate digoxin dosing in patients undergoing continuous venovenous hemodiafiltration, anecdotal evidence-guided digoxin dosing was performed for this patient using plasma digoxin concentration-based therapeutic drug monitoring. We use this case to demonstrate the potential role of physiologically based pharmacokinetic modeling in assisting therapeutic decision making. (Sou...
Source: Therapeutic Drug Monitoring - January 14, 2020 Category: Drugs & Pharmacology Tags: Grand Rounds Source Type: research

Dried Blood Spot Analysis for Therapeutic Drug Monitoring of Antipsychotics: Drawbacks of Its Clinical Application: Erratum
No abstract available (Source: Therapeutic Drug Monitoring)
Source: Therapeutic Drug Monitoring - November 18, 2019 Category: Drugs & Pharmacology Tags: Erratum Source Type: research

Distribution of Psychotropic Drugs Into Lipoproteins
Conclusions: The present results indicate that psychotropic drugs with certain characteristics bind to LDL/VLDL in blood. This further implies that lipoproteins could play an important role in drug transport. (Source: Therapeutic Drug Monitoring)
Source: Therapeutic Drug Monitoring - November 18, 2019 Category: Drugs & Pharmacology Tags: Short Communication Source Type: research

A Dried Blood Spot Analysis for Solithromycin in Adolescents, Children, and Infants: A Short Communication
Conclusions: Solithromycin concentrations in DBS were similar to those measured in LPS and did not require correction for hematocrit or protein binding. (Source: Therapeutic Drug Monitoring)
Source: Therapeutic Drug Monitoring - November 18, 2019 Category: Drugs & Pharmacology Tags: Short Communication Source Type: research

Prednisolone Concentrations in Plasma (Total and Unbound) and Saliva of Adult Kidney Transplant Recipients
Conclusions: Total and free plasma prednisolone measurements correlated poorly with saliva measurements; however, correlation improved when concentrations early in the dosing interval were excluded. (Source: Therapeutic Drug Monitoring)
Source: Therapeutic Drug Monitoring - November 18, 2019 Category: Drugs & Pharmacology Tags: Short Communication Source Type: research

Chinese Patients With Heart Valve Replacement Do Not Benefit From Warfarin Pharmacogenetic Testing on Anticoagulation Outcomes
Background: Genotype-guided warfarin dosing has been shown in some randomized trials to improve anticoagulation outcomes in individuals of European ancestry; yet, its utility in Chinese patients with heart valve replacement remains unresolved. Methods: A total of 2264 patients who underwent heart valve replacement at Wuhan Asia Heart Hospital were enrolled in this study. Patients were randomly divided into 2 groups, namely, a genotype-guided and a traditional clinically guided warfarin dosing group. In the genotype-guided group (n = 1134), genotyping for CYP2C9 and VKORC1 (−1639 G→A) was performed using Taq...
Source: Therapeutic Drug Monitoring - November 18, 2019 Category: Drugs & Pharmacology Tags: Original Article Source Type: research

Pharmacokinetic/Pharmacodynamic Analysis of Voriconazole Against Candida spp. and Aspergillus spp. in Allogeneic Stem Cell Transplant Recipients
Conclusions: The PK simulations in this study suggest that transplant recipients on voriconazole prophylaxis against invasive candidiasis or aspergillosis are likely to achieve the target concentrations associated with the desired treatment outcomes if the maintenance dose is 200 mg twice daily. However, Aspergillus spp. with high minimal inhibitory concentrations could require higher maintenance doses. (Source: Therapeutic Drug Monitoring)
Source: Therapeutic Drug Monitoring - November 18, 2019 Category: Drugs & Pharmacology Tags: Original Article Source Type: research

Linezolid Dosing in Patients With Liver Cirrhosis: Standard Dosing Risk Toxicity
The objective of this study was to evaluate the pharmacokinetics, efficacy and safety of linezolid in cirrhotic patients. Methods: A case–control 1:1 study of patients undergoing linezolid therapeutic drug monitoring was conducted between January 2015 and June 2017. Cases with liver cirrhosis were matched with controls by age, body weight, comorbidities, renal function, and intensive care unit (ICU) admission. Results: Fifty-two patients were included, 26 in each group. Patients with Child–Pugh Scores A, B, and C were 1 (3.8%), 13 (50.0%), and 12 (46.2%), respectively. Cases had higher median linezolid tr...
Source: Therapeutic Drug Monitoring - November 18, 2019 Category: Drugs & Pharmacology Tags: Original Article Source Type: research

Comparison of the Area Under the Curve for Vancomycin Estimated Using Compartmental and Noncompartmental Methods in Adult Patients With Normal Renal Function
Background: Vancomycin pharmacokinetics are best described using a 2-compartment model. However, 1-compartment population models are commonly used as the basis for dose prediction software. Therefore, the validity of using a 1-compartment model to guide vancomycin drug dosing was examined. Methods: Published plasma concentration–time data from adult subjects (n = 30) with stable renal function administered a single intravenous infusion of vancomycin were extracted from previous studies. The vancomycin area under the curve (AUC0–∞) was calculated for each subject using noncompartmental methods (AUCNCA...
Source: Therapeutic Drug Monitoring - November 18, 2019 Category: Drugs & Pharmacology Tags: Original Article Source Type: research

Nonparametric Population Pharmacokinetic Modeling of Isoniazid in Colombian Patients With Tuberculosis
Conclusions: The Monte Carlo simulation indicated that 300 mg of INH per day is appropriate for Mycobacterium tuberculosis strains with minimal inhibitory concentration (MIC) up to 0.03 mg/L (target: area under the concentration–time curve/MIC>597); however, to cover strains with MIC up to 0.125 mg/L (80% of clinical isolates), a dose of 900 mg per day would be required. (Source: Therapeutic Drug Monitoring)
Source: Therapeutic Drug Monitoring - November 18, 2019 Category: Drugs & Pharmacology Tags: Original Article Source Type: research

Quality Assessment of Dried Blood Spots from Patients With Tuberculosis from 4 Countries
Conclusions: New tools to help obtain blood spots of sufficient quality are necessary and environmental specific recommendations to determine plasma concentration correctly. In addition, 3% of the DBS cards were rejected because the integrity of the materials suggesting that the quality of plastic ziplock bags currently used to protect the DBS cards against contamination and humidity may not be sufficient. (Source: Therapeutic Drug Monitoring)
Source: Therapeutic Drug Monitoring - November 18, 2019 Category: Drugs & Pharmacology Tags: Original Article Source Type: research

Pharmacokinetics of Enteric-Coated Mycophenolate Sodium in Lupus Nephritis (POEMSLUN)
Conclusions: CC participants reached target AUC0-12 quicker. Larger studies are required to test clinical efficacy. (Source: Therapeutic Drug Monitoring)
Source: Therapeutic Drug Monitoring - November 18, 2019 Category: Drugs & Pharmacology Tags: Original Article Source Type: research

Generation and Validation of a Limited Sampling Strategy to Monitor Mycophenolic Acid Exposure in Children With Nephrotic Syndrome
Conclusions: An abbreviated profile within the first 2 hours after MMF dosing gives a good estimate of MPA exposure in children with nephrotic syndrome and hence has the potential to optimize MMF therapy. (Source: Therapeutic Drug Monitoring)
Source: Therapeutic Drug Monitoring - November 18, 2019 Category: Drugs & Pharmacology Tags: Original Article Source Type: research

Reversible Impaired Methotrexate Clearance After Platinum-Based Chemotherapy for Osteosarcoma
Abstract: The authors present a case of an 18-year-old man with metastasized osteosarcoma, admitted for methotrexate (MTX) treatment combined with cisplatin and doxorubicin. During the first cycle, severe MTX toxicity was observed with increased MTX serum levels and delayed MTX clearance requiring rescue treatment with intensified leucovorin. In the following cycles, cisplatin and doxorubicin were discontinued, and MTX dose was reduced. The elimination half-life slowly improved over the following cycles suggesting a reversible cause responsible for reduced MTX clearance and toxicity during the first cycle. Cisplatin is w...
Source: Therapeutic Drug Monitoring - November 18, 2019 Category: Drugs & Pharmacology Tags: Grand Round Source Type: research

Volumetric Absorptive Microsampling: A New Sampling Tool for Therapeutic Drug Monitoring of Antiepileptic Drugs
Conclusions: The assay allows for highly sensitive and selective quantification of several AEDs in whole blood samples collected by VAMS. The developed method is accurate and precise and free from matrix effects and volumetric HCT% bias. (Source: Therapeutic Drug Monitoring)
Source: Therapeutic Drug Monitoring - September 21, 2019 Category: Drugs & Pharmacology Tags: Original Article Source Type: research

Population Pharmacokinetic Analysis of Phenytoin After Intravenous Administration of Fosphenytoin in Adult and Elderly Epileptic Patients
Conclusions: We herein developed a PPK model to describe phenytoin concentrations after the intravenous administration of fosphenytoin. Age was identified as a significant covariate for CL. (Source: Therapeutic Drug Monitoring)
Source: Therapeutic Drug Monitoring - September 21, 2019 Category: Drugs & Pharmacology Tags: Original Article Source Type: research

Glomerular Filtration Rate Is a Major Predictor of Clearance of Oxcarbazepine Active Metabolite in Adult Chinese Epileptic Patients: A Population Pharmacokinetic Analysis
Conclusions: Glomerular filtration rate was first found as an important covariate influencing MHD CL. A PPK model was established to estimate the individual MHD CL for adult patients taking OXC and may be applied for individualizing doses in the target population. (Source: Therapeutic Drug Monitoring)
Source: Therapeutic Drug Monitoring - September 21, 2019 Category: Drugs & Pharmacology Tags: Original Article Source Type: research

Interlaboratory Analysis of Isavuconazole Plasma Concentration Assays Among European Laboratories
Conclusions: Alignment of methodologies among laboratories may be warranted to improve the accuracy and reproducibility of therapeutic drug measurements. (Source: Therapeutic Drug Monitoring)
Source: Therapeutic Drug Monitoring - September 21, 2019 Category: Drugs & Pharmacology Tags: Original Article Source Type: research

Anthropometric and Genetic Factors Associated With the Exposure of Rifampicin and Isoniazid in Mexican Patients With Tuberculosis
Conclusions: Anthropometric, genetic, and dosage characteristics of Mexican patients with TB are an important source of risk for subtherapeutic plasma concentrations of anti-TB drugs. Factors such as lower-than-recommended RMP dose, male patients with TB, and MDR1 3435 genotype, in addition to age group, body mass index, and INH acetylator phenotype based on NAT2 genotype, should be considered during treatment. (Source: Therapeutic Drug Monitoring)
Source: Therapeutic Drug Monitoring - September 21, 2019 Category: Drugs & Pharmacology Tags: Original Article Source Type: research

Simultaneous Quantification of Free Adalimumab and Infliximab in Human Plasma Using a Target-Based Sample Purification and Liquid Chromatography–Tandem Mass Spectrometry
Conclusions: This method provides an easy, efficient, and cost-effective workflow for therapeutic drug monitoring patients treated with ADM or IFX. (Source: Therapeutic Drug Monitoring)
Source: Therapeutic Drug Monitoring - September 21, 2019 Category: Drugs & Pharmacology Tags: Original Article Source Type: research

Clinical Consequences of Antibody Formation, Serum Concentrations, and HLA-Cw6 Status in Psoriasis Patients on Ustekinumab
Background: Ustekinumab for the treatment of psoriasis is currently administered in a standard dosing regimen. However, some patients tend to benefit from alternative dosing regimens, a step toward personalized medicine. Methods: To investigate the role of ustekinumab serum concentrations, anti-ustekinumab antibodies [AUA] and HLA-Cw6 status as tools for optimizing ustekinumab treatment, a multicenter prospective cohort study was conducted at an academic hospital with affiliated nonacademic hospitals in Belgium (cohort 1) and 2 academic hospitals in the Netherlands (cohort 2 and 3). Patients with plaque-type psoriasis...
Source: Therapeutic Drug Monitoring - September 21, 2019 Category: Drugs & Pharmacology Tags: Original Article Source Type: research

Interior Temperature and Relative Humidity of an Envelope During Mail Transport by the Japan Post in the Summer: Preliminary Study for a Stability Test of Dried Blood Spot Samples Sent as Regular Mail
Conclusions: Both zip lock bags provided comparable results in relation to the interior temperature and RH of the envelope. Our results suggest that a stability test at 40°C and 90% RH for at least 24 hours is recommended as a validation process if DBS samples are transported as regular mail in Japan. However, conditions may need to be modified depending on the regions. (Source: Therapeutic Drug Monitoring)
Source: Therapeutic Drug Monitoring - September 21, 2019 Category: Drugs & Pharmacology Tags: Original Article Source Type: research

Tacrolimus Levels in the Prophylaxis of Acute Graft-Versus-Host Disease in the Chinese Early After Hematopoietic Stem Cell Transplantation
Conclusions: Tacrolimus therapeutic drug monitoring improved treatment outcomes of Chinese alloHSCT recipients. Cv measurements during weeks 3–4 and C0 or C2 measurements during weeks 5–6 better predicted aGVHD (I–IV) than the concentrations measured at other time points during the first 6 weeks after alloHSCT. (Source: Therapeutic Drug Monitoring)
Source: Therapeutic Drug Monitoring - September 21, 2019 Category: Drugs & Pharmacology Tags: Original Article Source Type: research

Estimation of Blood Sirolimus Concentration Based on Tacrolimus Concentration/Dose Normalized by Body Weight Ratio in Lung Transplant Patients
Background: Sirolimus and tacrolimus require accurate drug dosing based on their target blood levels to produce better clinical outcomes, specifically, the avoidance of drug-induced adverse effects and the maintenance of efficacy. However, because the ideal dose of sirolimus and the schedule for measuring its blood levels are unclear in lung transplant patients, an index is required for estimating sirolimus blood concentrations. The aim of this work is to study the correlation between the trough concentration/dose normalized by body weight (C0/D) ratios of sirolimus and tacrolimus in lung transplant patients. Methods: ...
Source: Therapeutic Drug Monitoring - September 21, 2019 Category: Drugs & Pharmacology Tags: Original Article Source Type: research

Tacrolimus Can Be Reliably Measured With Volumetric Absorptive Capillary Microsampling Throughout the Dose Interval in Renal Transplant Recipients
Conclusions: The microsample method demonstrated acceptable performance. Tac concentrations can be reliably quantified throughout the dose interval by using volumetric absorptive microsampling in renal transplant recipients, and the results are not influenced by postal shipment. (Source: Therapeutic Drug Monitoring)
Source: Therapeutic Drug Monitoring - September 21, 2019 Category: Drugs & Pharmacology Tags: Original Article Source Type: research

Development and Validation of a Sensitive UHPLC-MS/MS–Based Method for the Analysis of Folylpolyglutamate Synthetase Enzymatic Activity in Peripheral Blood Mononuclear Cells: Application in Rheumatoid Arthritis and Leukemia Patients
Conclusions: Collectively, given its sensitivity with low cell numbers and avoidance of radioactive substrates, UHPLC-MS/MS–based analysis of FPGS activity may be eligible for routine therapeutic drug monitoring of MTX in RA and leukemia for therapy (non)response evaluations. (Source: Therapeutic Drug Monitoring)
Source: Therapeutic Drug Monitoring - September 21, 2019 Category: Drugs & Pharmacology Tags: Original Article Source Type: research

Impact of Cachexia and Opioid Analgesic Cotreatment on Pregabalin Pharmacokinetics and Central Nervous System Symptoms in Cancer Patients
Conclusions: In patients with cancer, steady-state trough plasma pregabalin concentrations were altered with renal function, systemic inflammation, and opioid analgesic cotreatment. However, a higher incidence of CNS symptoms observed in patients with cancer on pregabalin was more related to cachexia and opioid analgesic cotreatment than to altered pregabalin concentrations. (Source: Therapeutic Drug Monitoring)
Source: Therapeutic Drug Monitoring - September 21, 2019 Category: Drugs & Pharmacology Tags: Original Article Source Type: research

Association of Hepatic Nuclear Factor 4 Alpha Gene Polymorphisms With Free Imatinib Plasma Levels and Adverse Reactions in Chinese Gastrointestinal Stromal Tumor Patients
This study investigated the effect of genetic variants in hepatocyte nuclear factor 4 alpha (HNF4α, encoded by gene NR2A1), a pivotal transcriptional regulator of drug disposition genes, on dose-adjusted IM-free plasma levels and related adverse reactions in Chinese GIST patients. Methods: Five common polymorphisms of NR2A1 (rs3818247, rs1884613, rs2071197, rs2425640, and rs736824) were genotyped in 70 Chinese GIST patients who had been administered IM 300–600 mg/d. The free IM trough plasma levels were determined based on a method of ultrafiltration coupled with high performance liquid chromatography-tandem...
Source: Therapeutic Drug Monitoring - September 21, 2019 Category: Drugs & Pharmacology Tags: Original Article Source Type: research

Evaluation of Medication Adherence and Pharmacokinetics of Dasatinib for Earlier Molecular Response in Japanese Patients With Newly Diagnosed Chronic Myeloid Leukemia: A Pilot Study
Conclusions: A Medication Event Monitoring System was applied for the direct evaluation of oral dasatinib adherence for the first time, and the clinical effect of dasatinib was investigated under the strict monitoring of patient adherence. Although this study had a small sample size, the plasma concentration monitoring of dasatinib is considered to be useful to predict an earlier molecular response with fewer edematous adverse events. (Source: Therapeutic Drug Monitoring)
Source: Therapeutic Drug Monitoring - September 21, 2019 Category: Drugs & Pharmacology Tags: Original Article Source Type: research

Therapeutic Drug Monitoring of Everolimus in Oncology: Evidences and Perspectives
Abstract: Everolimus is a mammalian target of rapamycin (m-TOR) inhibitor that has been approved for the treatment of hormone receptor-positive advanced breast cancer, metastatic renal cancer, and neuroendocrine tumors. Although therapeutic drug monitoring (TDM) of everolimus is well established in the transplantation field, it is not currently performed in oncology. The last consensus conference about the TDM of everolimus states that for the use of everolimus in oncology, “further studies are required to determine the clinical utility of TDM for everolimus in oncology settings.” In this review, the authors ...
Source: Therapeutic Drug Monitoring - September 21, 2019 Category: Drugs & Pharmacology Tags: Review Article Source Type: research