{"title":"One Concentration Does Not Fit All: It is Time to Personalize the Therapeutic Range of Infliximab in Crohn Disease.","authors":"Bénédicte Franck, Camille Tron, Marie-Clémence Verdier, Eric Bellissant, Anne-Sophie Peaucelle, Xavier Roblin, Florian Lemaitre, Guillaume Bouguen","doi":"10.1097/FTD.0000000000001251","DOIUrl":"https://doi.org/10.1097/FTD.0000000000001251","url":null,"abstract":"<p><strong>Background: </strong>Therapeutic drug monitoring of infliximab is commonly performed based on trough concentration. However, doses and dosing intervals may be adapted to patient outcomes, and this trough concentration target may correspond to a large range of exposures in terms of the area under the concentration-time curve (AUC). The objectives of this study were to assess the real-life exposure to intravenous infliximab in patients with Crohn disease in remission at year 1 and to assess the evolution of exposure in patients who switched to subcutaneous infliximab.</p><p><strong>Methods: </strong>The authors conducted a retrospective observational pharmacokinetic study in patients with Crohn disease who had available infliximab concentrations during intravenous and subcutaneous infliximab maintenance therapy as per the standard of care. Infliximab exposure parameters (AUCs and trough concentrations, C0) were compared for different dosing regimens of intravenous infliximab before (intravenous) and after (subcutaneous) the switch.</p><p><strong>Results: </strong>A total of 113 patients had 383 intravenous infliximab concentrations. Dosing intervals ranged from 4 to 12 weeks. The median/range/CV% C0, AUC0-t, and AUC0-8weeks were 5.3 mcg/mL [<LLoQ-49.6]/71.6%, 37,792 mcg.h/mL [4971-116,366]/33.1%, and 41,582 mcg.h/mL [7953-232,048]/43.9%, respectively. Forty-one patients had available paired C0 after both intravenous and subcutaneous administration. A poor correlation was found between preswitch intravenous infliximab C0 and postswitch subcutaneous infliximab C0.</p><p><strong>Conclusions: </strong>In this study, the authors suggested that in patients treated with IV IFX, different targets of C0 should be proposed according to treatment schemes and that AUC0-t might be a relevant determinant of clinical remission. Moreover, exposure did not remain stable throughout the switch from IV to SC IFX in any patient. These variations may depend on the intravenous dosing interval before switching.</p>","PeriodicalId":23052,"journal":{"name":"Therapeutic Drug Monitoring","volume":" ","pages":""},"PeriodicalIF":2.8,"publicationDate":"2024-11-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142772640","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Alternate Sampling Matrices for Therapeutic Drug Monitoring of Immunosuppressants.","authors":"Benedetta C Sallustio","doi":"10.1097/FTD.0000000000001282","DOIUrl":"https://doi.org/10.1097/FTD.0000000000001282","url":null,"abstract":"<p><strong>Background: </strong>Immunosuppressant (IS) therapeutic drug monitoring (TDM) relies on measuring mostly pharmacologically inactive erythrocyte-bound and/or plasma protein-bound drug levels. Variations in hematocrit and plasma protein levels complicate interpretation of blood calcineurin inhibitor (CNI) and inhibitors of the molecular target of rapamycin (mTORi) concentrations. Variable binding of mycophenolic acid (MPA) to albumin similarly complicates its TDM in plasma. A different matrix may improve IS concentration-response relationships and better reflect exposures at sites of action.</p><p><strong>Methods: </strong>This review explores the evidence for IS TDM using peripheral blood mononuclear cell (PBMC), graft tissue, and total or unbound plasma concentrations.</p><p><strong>Results: </strong>Tandem mass spectrometry provides the sensitivity for assessing these matrices. But several challenges must be addressed, including minimizing hemolysis during blood collection, preventing IS efflux during PBMC preparation, and determining the need for further purification of the PBMC fraction. Assessing and reducing nonspecific binding during separation of unbound IS are also necessary, especially for lipophilic CNIs/mTORi. Although TDM using PBMC or unbound plasma concentrations may not be feasible due to increased costs, plasma CNI/mTORi levels may be more easily integrated into routine TDM. However, no validated TDM targets currently exist, and published models to adjust blood CNI/mTORi concentrations for hematocrit or to predict PBMC, and total and unbound plasma IS concentrations have yet to be validated in terms of measured concentrations or prediction of clinical outcomes.</p><p><strong>Conclusions: </strong>Even if CNI/mTORi measurements in novel matrices do not become routine, they may help refine pharmacokinetic-pharmacodynamic relationships and improve mathematical models for TDM using whole blood. Notably, there is evidence to support measuring unbound MPA in patients with severe renal dysfunction, hypoalbuminemia, and hyperbilirubinemia, with some proposed TDM targets.</p>","PeriodicalId":23052,"journal":{"name":"Therapeutic Drug Monitoring","volume":" ","pages":""},"PeriodicalIF":2.8,"publicationDate":"2024-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142732764","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Sibylle Reber, Alexandra S Herr, Stefan Unterecker, Maike Scherf-Clavel
{"title":"Serum Concentration of Antidepressant Drugs in Geriatric Day Care Patients With Renal Insufficiency and Multimorbidity.","authors":"Sibylle Reber, Alexandra S Herr, Stefan Unterecker, Maike Scherf-Clavel","doi":"10.1097/FTD.0000000000001285","DOIUrl":"https://doi.org/10.1097/FTD.0000000000001285","url":null,"abstract":"<p><strong>Background: </strong>Geriatric depression is challenging to treat owing to age-related changes in pharmacokinetics and comorbidities. Although renal insufficiency and multimorbidity are typical geriatric complications that cannot be completely separated from each other, no study has examined the influence of these factors on the serum concentrations of antidepressants. For the first time, we evaluated the effects of these factors in combination on the dose-corrected serum concentration (C/D) of antidepressants in geriatric patients.</p><p><strong>Methods: </strong>In this retrospective study, data from 123 geriatric patients in a gerontopsychiatric day care unit at the University Hospital of Würzburg were analyzed. Multiple linear regression analysis and analysis of variance with confounders were used to examine the associations between glomerular filtration rate (GFR) and stages of renal impairment and the C/D of venlafaxine, mirtazapine, sertraline, and escitalopram corrected for multimorbidity, sex, lithium intake, and the number of triple whammy drugs.</p><p><strong>Results: </strong>GFR (P < 0.001, ß = -0.070) was associated with the C/D of the active moiety of venlafaxine (N = 32). GFR, multimorbidity, and sex were not associated with the C/D of mirtazapine, escitalopram, or sertraline.</p><p><strong>Conclusions: </strong>As the influence of sex may be less pronounced than that of decreasing GFR in terms of the C/D of the active moiety of venlafaxine in geriatric patients, we recommend considering the GFR for dose adjustment rather than sex. In conclusion, even in patients with mild renal impairment, serum venlafaxine concentration should be monitored to prevent overdosing. Mirtazapine, sertraline, and escitalopram may be well-suited antidepressants for geriatric patients with renal function impairment stage 2-3 as well as multimorbidity.</p>","PeriodicalId":23052,"journal":{"name":"Therapeutic Drug Monitoring","volume":" ","pages":""},"PeriodicalIF":2.8,"publicationDate":"2024-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142717183","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Tessa Born-Bondt van den, Niels Westra, Katarzyna Krzywicka, Harmen R Moes, Manon Schuls-Fouchier, Daan J Touw, Oude Munnink Thijs H
{"title":"Midazolam Boosting With Cobicistat in a Patient With Drug-Resistant Epilepsy and Focal Status Epilepticus.","authors":"Tessa Born-Bondt van den, Niels Westra, Katarzyna Krzywicka, Harmen R Moes, Manon Schuls-Fouchier, Daan J Touw, Oude Munnink Thijs H","doi":"10.1097/FTD.0000000000001283","DOIUrl":"https://doi.org/10.1097/FTD.0000000000001283","url":null,"abstract":"<p><strong>Background: </strong>This report presents the case of a patient with drug-resistant epilepsy. Despite treatment with 4 antiepileptic drugs, the patient experienced an increasing frequency of focal seizures, necessitating hospitalization, and continuous intravenous midazolam infusion.</p><p><strong>Methods: </strong>Cobicistat was introduced as a pharmacokinetic booster to decrease the metabolic clearance of midazolam, leading to increased exposure and an extended half-life.</p><p><strong>Results: </strong>Cobicistat boosting allowed the switch from intravenous to oral midazolam, and the patient was discharged on an oral midazolam regimen.</p><p><strong>Conclusions: </strong>Cobicistat can be effectively used to boost midazolam exposure pharmacokinetically in patients with drug-resistant epilepsy who require stable midazolam blood concentrations.</p>","PeriodicalId":23052,"journal":{"name":"Therapeutic Drug Monitoring","volume":" ","pages":""},"PeriodicalIF":2.8,"publicationDate":"2024-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142676932","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Gretchen N de Graav, Suwasin Udomkarnjananun, Carla C Baan, Marlies E J Reinders, Joke I Roodnat, Brenda C M de Winter, Dennis A Hesselink
{"title":"New Developments and Therapeutic Drug Monitoring Options in Costimulatory Blockade in Solid Organ Transplantation: A Systematic Critical Review.","authors":"Gretchen N de Graav, Suwasin Udomkarnjananun, Carla C Baan, Marlies E J Reinders, Joke I Roodnat, Brenda C M de Winter, Dennis A Hesselink","doi":"10.1097/FTD.0000000000001275","DOIUrl":"https://doi.org/10.1097/FTD.0000000000001275","url":null,"abstract":"<p><strong>Purpose: </strong>In this review, the authors summarized the latest developments in costimulatory blockade to prevent rejection after solid organ transplantation (SOT) and discussed possibilities for future research and the need for therapeutic drug monitoring (TDM) of these agents.</p><p><strong>Methods: </strong>Studies about costimulatory blockers in SOT in humans or animal transplant models in the past decade (2014-2024) were systematically reviewed in PubMed, European Union clinical trials (EudraCT), and ClinicalTrials.gov.</p><p><strong>Results: </strong>Seventy-five registered clinical trials and 58 published articles were found on costimulation blockade of the CD28-CD80/86, CD40-CD40L, and OX40-OX40L pathways. Belatacept, an antagonist of the CD28-CD80/86 pathway, is the only approved costimulatory agent in SOT, hence accounting for most of the research. Other identified costimulatory blocking agents included abatacept and CD28 antagonists tegoprubart, dazodalibep, and TNX-1500. Although tegoprubart was unsuccessful in pancreas transplantation in nonhuman primates, trials in human kidney transplantation are underway. Dazodalibep trials faced recruitment challenges. TNX-1500 was unsuccessful in animal studies and is currently not pursued in humans. After discontinuation of iscalimab (CD40-CD154 pathway antagonist) in SOT, the alternatives, bleselumab and KPL404, showed promising results in kidney transplantation and cardiac xenotransplantation. Studies on secondary costimulatory pathway antagonists, such as OX40-OX40L, have only used animal models. Despite the low interindividual variability in pharmacokinetics (PK) in all studied agents, TDM could be useful for optimizing dosing in PK/pharmacodynamic (PD) studies.</p><p><strong>Conclusions: </strong>The routine use of costimulation blockade in SOT is hindered by problems in efficacy compared with the standard of care. Costimulatory inhibitors could be combined in a calcineurin inhibitor-free regimen. Future PK/pharmacodynamic studies in costimulatory agents and personalized medicine could warrant TDM of these agents.</p>","PeriodicalId":23052,"journal":{"name":"Therapeutic Drug Monitoring","volume":" ","pages":""},"PeriodicalIF":2.8,"publicationDate":"2024-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142682886","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Nils Tore Vethe, Anders Åsberg, Stein Bergan, Ida Robertsen, Karsten Midtvedt
{"title":"Implementation of Volumetric Finger-Prick Self-Sampling for TDM of Immunosuppressants After Kidney Transplantation: Lessons Learned from the Practice.","authors":"Nils Tore Vethe, Anders Åsberg, Stein Bergan, Ida Robertsen, Karsten Midtvedt","doi":"10.1097/FTD.0000000000001281","DOIUrl":"10.1097/FTD.0000000000001281","url":null,"abstract":"<p><strong>Background: </strong>Home-based hospital services are becoming increasingly popular, and the addition of remote outpatient appointments after kidney transplantation facilitates more practical and closer follow-up. In this context, finger-prick self-sampling is an important aspect of monitoring of immunosuppressants and biomarkers. Nevertheless, several issues must be addressed to ensure the feasibility and quality when implementing microsampling in clinical practice. We summarize our experiences and opinions in this field.</p><p><strong>Methods: </strong>This article is based on the authors' experience regarding the laboratory and clinical implementation of finger-prick self-sampling in kidney transplant recipients. The referenced literature is related to the authors' knowledge in this field.</p><p><strong>Results: </strong>We present considerations for the selection of relevant analytes, key characteristics of selected volumetric sampling tools (Mitra and Capitainer), and the associated sampling pitfalls. In addition, we address the requirements for patients performing finger-prick sampling, appropriate design of methods and workflow, critical points for validation, and aspects related to logistics and digital solutions.</p><p><strong>Conclusions: </strong>Volumetric finger-prick self-sampling is suitable for monitoring immunosuppressants and certain biomarkers that are relevant to outpatient follow-up after kidney transplantation. We believe that a carefully designed system for the entire workflow, including patient training, will be beneficial in enabling a safe experience for transplant recipients, as well as ensuring overall efficiency and adequate quality. In the future, a combination of immunosuppressants with a wide range of biomarkers has significant potential for use in at-home self-sampling after kidney transplantation.</p>","PeriodicalId":23052,"journal":{"name":"Therapeutic Drug Monitoring","volume":" ","pages":""},"PeriodicalIF":2.8,"publicationDate":"2024-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142669307","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Femke Hooijberg, Stefan P H van den Berg, Zohra Layegh, Maureen Leeuw, Ori Elkayam, Annick de Vries, Mike Nurmohamed, Theo Rispens, Thomas P C Dorlo, Gertjan Wolbink
{"title":"Precision Dosing of Intravenous Tocilizumab: Development of Pharmacokinetic Model-Derived Tapering Strategies for Patients With Rheumatoid Arthritis.","authors":"Femke Hooijberg, Stefan P H van den Berg, Zohra Layegh, Maureen Leeuw, Ori Elkayam, Annick de Vries, Mike Nurmohamed, Theo Rispens, Thomas P C Dorlo, Gertjan Wolbink","doi":"10.1097/FTD.0000000000001258","DOIUrl":"https://doi.org/10.1097/FTD.0000000000001258","url":null,"abstract":"<p><strong>Background: </strong>Tocilizumab targets the interleukin-6 receptor, and dosing is complex owing to its nonlinear clearance related to target binding. Therefore, tapering tocilizumab requires a different approach than that of tumor necrosis factor inhibitors (TNFi). This study aimed to identify these differences and enable personalized treatment of rheumatoid arthritis (RA) beyond TNFi therapy.</p><p><strong>Methods: </strong>A population pharmacokinetic model of intravenous tocilizumab was developed using data from a randomized controlled trial of dose tapering in patients with RA. Subsequent population-level Monte Carlo and individual Bayesian simulations were performed to create tapering strategies involving dose reduction and interval extension. The target trough concentration of tocilizumab was 5 mg/L. Finally, the drug savings were compared between the 2 methods.</p><p><strong>Results: </strong>The pharmacokinetic of tocilizumab was described with a 2-compartment model with parallel linear (CL 0.20 L/d) and nonlinear (VM 5.2 mg/d, KM 0.19 mg/L) elimination. The linear clearance rate and central volume of distribution increased with lean body mass, and men exhibited higher clearance rates than women. The simulated concentration-time profiles demonstrated that, owing to nonlinear clearance, drug concentrations decreased more than dose-proportionally with lower doses. Tapering based on an individual Bayesian approach emerged as the most promising strategy, yielding a 39% reduction in drug use across virtual populations.</p><p><strong>Conclusions: </strong>Tapering strategies were developed for intravenous tocilizumab, offering potential application in patients with RA who have reached low disease activity or remission, pending clinical validation. The developed strategies demonstrate that the tapering of tocilizumab should be approached more carefully and in smaller steps than that of TNFi.</p>","PeriodicalId":23052,"journal":{"name":"Therapeutic Drug Monitoring","volume":" ","pages":""},"PeriodicalIF":2.8,"publicationDate":"2024-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142605620","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Amelia R Cossart, Nicole M Isbel, Scott B Campbell, Brett McWhinney, Christine E Staatz
{"title":"Examining Whole Blood, Total and Free Plasma Tacrolimus in Elderly Kidney Transplant Recipients.","authors":"Amelia R Cossart, Nicole M Isbel, Scott B Campbell, Brett McWhinney, Christine E Staatz","doi":"10.1097/FTD.0000000000001274","DOIUrl":"https://doi.org/10.1097/FTD.0000000000001274","url":null,"abstract":"<p><strong>Background: </strong>Therapeutic monitoring is routinely performed to ensure tacrolimus whole-blood concentrations fall within a predefined target. Despite this, patients still experience inefficacy and toxicity that could be related to variability in free (unbound) tacrolimus exposure. Therefore, the aim of this study was to compare tacrolimus-free plasma (Cu), total plasma (Cp), and whole-blood (Cwb) concentrations in adult kidney transplant recipients and to characterize tacrolimus disposition across different matrices.</p><p><strong>Methods: </strong>Twelve-hour concentration-time profiling was performed in 15 recipients, allowing simultaneous measurement of Cu, Cp, and Cwb. Pharmacokinetic parameters were estimated using noncompartmental analysis. The relationship between Cwb and Cp were examined using a capacity-limited binding model, incorporating the hematocrit fraction (fHCT) to estimate maximum binding concentration (Bmax) and dissociation constant (Kd). The relationship between Cp and Cu was evaluated using a linear binding model to estimate the nonspecific binding parameter (Nplasma). Nonlinear regression analysis was used to obtain estimates of Bmax, Kd, and Nplasma.</p><p><strong>Results: </strong>A total of 195 paired Cwb, Cp, and Cu values were collected. The median ratios of Cwb:Cp, Cp:Cu, and Cwb:Cu were 9:1, 20:1, and 138:1, respectively. Variability in free plasma exposure was large; free trough values ranged from 8 to 51 ng/L and free area-under-the-concentration-time-curve values ranged from 424 to 7160 ng·h/L. Median (range) estimates of Bmax, Kd, and Nplasma were 90.4 µg/L (22.4-752.5 µg/L), 2.36 µg/L (0-69.2 µg/L), and 0.05 (0.035-0.085), respectively. The interindividual variability (CV%) in binding parameters was considerable (Bmax 117.2%; Nplasma 32.5%).</p><p><strong>Conclusions: </strong>Large variability was observed in tacrolimus-free plasma exposure and binding parameters. Future research to characterize the relationship between tacrolimus Cu and patient outcomes may be of benefit.</p>","PeriodicalId":23052,"journal":{"name":"Therapeutic Drug Monitoring","volume":" ","pages":""},"PeriodicalIF":2.8,"publicationDate":"2024-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142605619","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Hailemichael Z Hishe, Sophie L Stocker, Lisa K Stamp, Nicola Dalbeth, Tony R Merriman, Daniel F B Wright
{"title":"Untangling the Exposure-Response Relationship of Allopurinol in the Setting of Chronic Kidney Disease and Diuretic Use: Implications for Dosing.","authors":"Hailemichael Z Hishe, Sophie L Stocker, Lisa K Stamp, Nicola Dalbeth, Tony R Merriman, Daniel F B Wright","doi":"10.1097/FTD.0000000000001265","DOIUrl":"https://doi.org/10.1097/FTD.0000000000001265","url":null,"abstract":"<p><strong>Background: </strong>Allopurinol dose reduction proportional to creatinine clearance (CLcr) results in suboptimal urate lowering in patients with gout. Similarly, diuretic therapy reduces oxypurinol clearance but is unexpectedly associated with the need for higher allopurinol doses to achieve the serum urate target (<0.36 mmol/L). The authors aimed to clarify the relationship between oxypurinol exposure and urate-lowering response in patients with gout at different stages of chronic kidney disease and those taking diuretics to determine the implications for maintenance dose selection.</p><p><strong>Methods: </strong>Oxypurinol and urate data from 5 clinical studies were available. Model-derived steady-state oxypurinol areas under the concentration-time curves (AUCss0-tau) were estimated using a Bayesian methodology. The observed response metrics included the percentage reduction in urate from baseline and achievement of the target urate level. Exposure-response was explored graphically and using logistic regression. In addition, the influence of chronic kidney disease and diuretic use on the allopurinol dose and oxypurinol AUCss0-tau requirements to achieve the serum urate target were explored.</p><p><strong>Results: </strong>Data from 258 patients with gout taking allopurinol representing 1288 paired steady-state oxypurinol and serum urate measurements were available. Higher oxypurinol exposure seems to be required for urate-lowering response normalization and achieve the serum urate target in individuals with reduced kidney function and those taking diuretics. However, allopurinol dose requirements were reduced by 2-fold at the extremes of kidney function and unchanged in those taking or not taking diuretics.</p><p><strong>Conclusions: </strong>A lower allopurinol maintenance dose was required in patients with reduced kidney function (CLcr <30 mL/min), but this was not proportional to CLcr. Diuretic therapy did not influence allopurinol dose requirements.</p>","PeriodicalId":23052,"journal":{"name":"Therapeutic Drug Monitoring","volume":" ","pages":""},"PeriodicalIF":2.8,"publicationDate":"2024-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142583630","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"miRNAs, dd-cf-DNA, and Chemokines as Potential Noninvasive Biomarkers for the Assessment of Clinical Graft Evolution and Personalized Immunosuppression Requirement in Solid Organ Transplantation.","authors":"Olga Millán, Judit Julian, Mercè Brunet","doi":"10.1097/FTD.0000000000001276","DOIUrl":"10.1097/FTD.0000000000001276","url":null,"abstract":"<p><strong>Abstract: </strong>The use of noninvasive biomarkers may reduce the need for biopsy and guide immunosuppression adjustments during transplantation. The scientific community in solid organ transplantation currently considers that chemokines, T- and B-cell immunophenotypes, and gene expression, among other molecular biomarkers, have great potential as diagnostic and predictive biomarkers for graft evolution; however, in clinical practice, few valid early biomarkers have emerged. This review focuses on the most relevant scientific advances in this field in the last 5 years regarding the role of 3 biomarkers: miRNAs, chemokines, and ddcf-DNA, in both adult and pediatric populations. An update was provided on the scores based on the combination of these biomarkers. The most-featured articles were identified through a literature search of the PubMed database. This review provides a comprehensive analysis of the potential clinical applications of these biomarkers in the diagnosis and prediction of graft outcomes and discusses the reasons why none have been implemented in clinical practice to date. Translating these biomarkers into routine clinical practice and combining them with pharmacogenetics and pharmacokinetic monitoring is challenging; however, it is the key to present/future individualized immunosuppressive therapies. It is essential that they be shown to be applicable and robust in real-life patient conditions and properly evaluate their added value when combined with the standard-of-care factor monitoring for graft clinical assessment. Partnership strategies among scientists, academic institutions, consortia, including expert working groups and scientific societies, and pharmaceutical and/or biotechnology companies should promote the development of prospective, randomized, multicenter intervention studies for adequate clinical validation of these biomarkers and their monitoring frequency, and their commercialization to make them available to transplant physicians.</p>","PeriodicalId":23052,"journal":{"name":"Therapeutic Drug Monitoring","volume":" ","pages":""},"PeriodicalIF":2.8,"publicationDate":"2024-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142583616","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}