{"title":"Implementing Pharmacogenetic Testing as a Risk Reduction Strategy for Drug Users: A Letter to the Editor.","authors":"Guillaume Drevin, Marie Briet, Chadi Abbara","doi":"10.1097/FTD.0000000000001262","DOIUrl":"https://doi.org/10.1097/FTD.0000000000001262","url":null,"abstract":"","PeriodicalId":23052,"journal":{"name":"Therapeutic Drug Monitoring","volume":null,"pages":null},"PeriodicalIF":2.8,"publicationDate":"2024-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142354324","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}
Satohiro Masuda, Florian Lemaitre, Markus J Barten, Stein Bergan, Maria Shipkova, Teun van Gelder, Sander Vinks, Eberhard Wieland, Kirsten Bornemann-Kolatzki, Mercè Brunet, Brenda de Winter, Maja-Theresa Dieterlen, Laure Elens, Taihei Ito, Kamisha Johnson-Davis, Pawel K Kunicki, Roland Lawson, Nuria Lloberas, Pierre Marquet, Olga Millan, Tomoyuki Mizuno, Dirk Jan A R Moes, Ofelia Noceti, Michael Oellerich, Smita Pattanaik, Tomasz Pawinski, Christoph Seger, Ron van Schaik, Raman Venkataramanan, Phil Walson, Jean-Baptiste Woillard, Loralie J Langman
{"title":"Everolimus Personalized Therapy: Second Consensus Report by the International Association of Therapeutic Drug Monitoring and Clinical Toxicology.","authors":"Satohiro Masuda, Florian Lemaitre, Markus J Barten, Stein Bergan, Maria Shipkova, Teun van Gelder, Sander Vinks, Eberhard Wieland, Kirsten Bornemann-Kolatzki, Mercè Brunet, Brenda de Winter, Maja-Theresa Dieterlen, Laure Elens, Taihei Ito, Kamisha Johnson-Davis, Pawel K Kunicki, Roland Lawson, Nuria Lloberas, Pierre Marquet, Olga Millan, Tomoyuki Mizuno, Dirk Jan A R Moes, Ofelia Noceti, Michael Oellerich, Smita Pattanaik, Tomasz Pawinski, Christoph Seger, Ron van Schaik, Raman Venkataramanan, Phil Walson, Jean-Baptiste Woillard, Loralie J Langman","doi":"10.1097/FTD.0000000000001250","DOIUrl":"https://doi.org/10.1097/FTD.0000000000001250","url":null,"abstract":"<p><strong>Abstract: </strong>The Immunosuppressive Drugs Scientific Committee of the International Association of Therapeutic Drug Monitoring and Clinical Toxicology established the second consensus report to guide Therapeutic Drug Monitoring (TDM) of everolimus (EVR) and its optimal use in clinical practice 7 years after the first version was published in 2016. This version provides information focused on new developments that have arisen in the last 7 years. For the general aspects of the pharmacology and TDM of EVR that have retained their relevance, readers can refer to the 2016 document. This edition includes new evidence from the literature, focusing on the topics updated during the last 7 years, including indirect pharmacological effects of EVR on the mammalian target of rapamycin complex 2 with the major mechanism of direct inhibition of the mammalian target of rapamycin complex 1. In addition, various concepts and technical options to monitor EVR concentrations, improve analytical performance, and increase the number of options available for immunochemical analytical methods have been included. Only limited new pharmacogenetic information regarding EVR has emerged; however, pharmacometrics and model-informed precision dosing have been constructed using physiological parameters as covariates, including pharmacogenetic information. In clinical settings, EVR is combined with a decreased dose of calcineurin inhibitors, such as tacrolimus and cyclosporine, instead of mycophenolic acid. The literature and recommendations for specific organ transplantations, such as that of the kidneys, liver, heart, and lungs, as well as for oncology and pediatrics have been updated. EVR TDM for pancreatic and islet transplantation has been added to this edition. The pharmacodynamic monitoring of EVR in organ transplantation has also been updated. These updates and additions, along with the previous version of this consensus document, will be helpful to clinicians and researchers treating patients receiving EVR.</p>","PeriodicalId":23052,"journal":{"name":"Therapeutic Drug Monitoring","volume":null,"pages":null},"PeriodicalIF":2.8,"publicationDate":"2024-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142354323","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}
Benedict Morath, Linda Schultes, Otto Roman Frey, Anka Christa Röhr, Hannes Christow, Torsten Hoppe-Tichy, Alexander Brinkmann, Ute Chiriac
{"title":"Development and Validation of a High-Performance Liquid Chromatography-Ultraviolet Spectrometry Method for Ampicillin and its Application in Routine Therapeutic Drug Monitoring of Intensive Care Patients.","authors":"Benedict Morath, Linda Schultes, Otto Roman Frey, Anka Christa Röhr, Hannes Christow, Torsten Hoppe-Tichy, Alexander Brinkmann, Ute Chiriac","doi":"10.1097/FTD.0000000000001253","DOIUrl":"https://doi.org/10.1097/FTD.0000000000001253","url":null,"abstract":"<p><strong>Background: </strong>Ampicillin/sulbactam, a combination of a β-lactam and β-lactamase inhibitor, is widely used in clinical settings. However, therapeutic drug monitoring (TDM) of ampicillin is not commonly performed, particularly in intensive care units (ICUs). The purpose of this study was to develop and validate a rapid and cost-effective high-performance liquid chromatography (HPLC)-ultraviolet spectrometry method to quantify ampicillin in human serum and evaluate its clinical application in ICU patients.</p><p><strong>Methods: </strong>Sample cleanup included a protein precipitation protocol, followed by chromatographic separation on a C18 reverse-phase HPLC column within 12.5 minutes using gradient elution of the mobile phase. The assay was validated according to the German Society of Toxicology and Forensic Chemistry criteria. Clinical applications involved the retrospective analysis of TDM data from ICU patients receiving continuous infusion of ampicillin/sulbactam, including the attainment of target ranges and individual predicted and observed pharmacokinetics.</p><p><strong>Results: </strong>The method was robust, with linear relations between the peak area responses and drug concentrations in the range of 2-128 mg/L. The coefficient of variation for precision and the bias for accuracy (both interday and intraday) were less than 10%. Clinical application revealed variable pharmacokinetics of ampicillin in ICU patients (clearance of 0.5-31.2 L/h). TDM-guided dose adjustments achieved good therapeutic drug exposure, with 92.9% of the samples being within the optimal (16-32 mg/L) or quasioptimal (8-48 mg/L) range.</p><p><strong>Conclusions: </strong>This method provides a practical solution for the routine TDM of ampicillin, facilitating individualized dosing strategies to ensure adequate therapeutic drug exposure. Given its simplicity, cost-effectiveness, and clinical relevance, HPLC-ultraviolet spectrometry holds promise for broad implementation in hospital pharmacies and clinical laboratories.</p>","PeriodicalId":23052,"journal":{"name":"Therapeutic Drug Monitoring","volume":null,"pages":null},"PeriodicalIF":2.8,"publicationDate":"2024-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142296134","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}
Angela Wu, Edward J Raack, Colin J D Ross, Bruce C Carleton
{"title":"Implementation and Evaluation Strategies for Pharmacogenetic Testing in Hospital Settings: A Scoping Review.","authors":"Angela Wu, Edward J Raack, Colin J D Ross, Bruce C Carleton","doi":"10.1097/FTD.0000000000001243","DOIUrl":"https://doi.org/10.1097/FTD.0000000000001243","url":null,"abstract":"<p><strong>Background: </strong>Pharmacogenetic testing in clinical settings has improved the safety and efficacy of drug treatment. There is a growing number of studies evaluating pharmacogenetic implementation and identifying barriers and facilitators. However, no review has focused on bridging the gap between identifying barriers and facilitators of testing and the clinical strategies adopted in response. This review was conducted to understand the implementation and evaluation strategies of pharmacogenetic testing programs.</p><p><strong>Methods: </strong>A PRISMA-compliant scoping review was conducted. The included studies discussed pharmacogenetic testing programs implemented in a hospital setting. Quantitative, qualitative, and mixed design methods were included.</p><p><strong>Results: </strong>A total of 232 of the 7043 articles that described clinical pharmacogenetic programs were included. The most common specialties that described pharmacogenetic implementation were psychiatry (26%) and oncology (16%), although many studies described institutional programs implemented across multiple specialties (19%). Different specialties reported different clinical outcomes, but all reported similar program performance indicators, such as test uptake and the number of times the test recommendations were followed. There were benefits and drawbacks to delivering test results through research personnel, pharmacists, and electronic alerts, but active engagement of physicians was necessary for the incorporation of pharmacogenetic results into clinical decision making.</p><p><strong>Conclusions: </strong>Further research is required on the maintenance and sustainability of pharmacogenetic testing initiatives. These findings provide an overview of the implementation and evaluation strategies of different specialties that can be used to improve pharmacogenetic testing.</p>","PeriodicalId":23052,"journal":{"name":"Therapeutic Drug Monitoring","volume":null,"pages":null},"PeriodicalIF":2.8,"publicationDate":"2024-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142296135","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}
Hamza Sayadi, Yeleen Fromage, Marc Labriffe, Clément Danthu, Caroline Monchaud, Jean-Baptiste Woillard
{"title":"Daptomycin Dosage Optimization in Renal Impairment Using Model-Informed Precision Dosing.","authors":"Hamza Sayadi, Yeleen Fromage, Marc Labriffe, Clément Danthu, Caroline Monchaud, Jean-Baptiste Woillard","doi":"10.1097/FTD.0000000000001256","DOIUrl":"https://doi.org/10.1097/FTD.0000000000001256","url":null,"abstract":"<p><strong>Background: </strong>Daptomycin's efficacy and toxicity are closely related to its exposure, which can vary widely among individuals. The patient, a 59-year-old male with an estimated glomerular filtration rate (eGFR) of 12 mL/min/1.73 m² and a weight of 64 kg, was treated with 850 mg of daptomycin every other day for infective endocarditis caused by methicillin-resistant Staphylococcus aureus (MRSA). For patients with an estimated glomerular filtration rate of less than 30 mL/min/1.73 m², the dosing recommendations are not explicitly defined in the endocarditis guidelines. Subsequently, the pharmacology department was contacted to adjust the dosage.</p><p><strong>Methods: </strong>A population pharmacokinetic model developed by Dvorchik et al. was used for Bayesian estimation of the patient's pharmacokinetic parameters. The 24-hour area under the curve (AUC24) of daptomycin was calculated at steady state using peak and trough plasma samples.</p><p><strong>Results: </strong>The minimum inhibitory concentration (MIC) of the MRSA strain was 0.25 mg/L. An AUC24/MIC ratio below 666 is associated with higher mortality risk, while an AUC24 above 939 h·mg/L correlates with increased risk of muscular toxicity. Initial AUC24 estimation was 1091 h·mg/L. Following a dosage reduction to 700 mg every other day, the AUC24 increased to 1600 h·mg/L. Further reduction to 500 mg every other day brought the AUC24 down to 750 h mg/L, with two subsequent measurements showing consistent AUC24 values of 500 h·mg/L, which is within the target range.</p><p><strong>Conclusions: </strong>Daptomycin ended 6 weeks after the initial negative blood culture, with no adverse effects or recurrence of MRSA infection. This case underscores the need for therapeutic drug monitoring and a multidisciplinary approach to adjust daptomycin doses in patients with renal impairment.</p>","PeriodicalId":23052,"journal":{"name":"Therapeutic Drug Monitoring","volume":null,"pages":null},"PeriodicalIF":2.8,"publicationDate":"2024-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142296133","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}
Shuyan Chen, Weiqiao Rao, Liang Fu, Guohui Liu, Jiancong Zhang, Yunli Liao, Ning Lv, Guofang Deng, Shijin Yang, Liang Lin, Lujin Li, Jiuxin Qu, Siqi Liu, Jin Zou
{"title":"Population Pharmacokinetic Modeling of Pyrazinamide Among Chinese Patients With Drug-Sensitive or Multidrug-Resistant Tuberculosis.","authors":"Shuyan Chen, Weiqiao Rao, Liang Fu, Guohui Liu, Jiancong Zhang, Yunli Liao, Ning Lv, Guofang Deng, Shijin Yang, Liang Lin, Lujin Li, Jiuxin Qu, Siqi Liu, Jin Zou","doi":"10.1097/FTD.0000000000001255","DOIUrl":"https://doi.org/10.1097/FTD.0000000000001255","url":null,"abstract":"<p><strong>Background: </strong>Pyrazinamide is used to treat drug-susceptible (DS) and multidrug-resistant (MDR) tuberculosis (TB). This study aimed to characterize the factors associated with the pharmacokinetic parameters of pyrazinamide and evaluate the disposition of the current regimen, which could provide suggestions for adequate dosing strategies for therapeutic targets.</p><p><strong>Methods: </strong>A population pharmacokinetic model of pyrazinamide was developed based on the data from 499 plasma concentrations from 222 Chinese patients diagnosed with DS or MDR TB. Pyrazinamide exposure was best described using a one-compartment model.</p><p><strong>Results: </strong>No significant differences were observed in the pharmacokinetic parameters between DS and MDR TB. The final covariate model showed that total body weight was the only significant covariate for apparent clearance, which increased by 0.45 L/h with a 10 kg increase in body weight. A simulation showed that for typical subjects weighing 40-80 kg, a fixed dosage of 1500 mg daily had an area under the concentration-time curve from 0 to 24 hours (AUC0-24) of 389.9-716.0 mg·h/L and peak serum concentrations of the drug (Cmax) of 32.2-44.8 mg/L.</p><p><strong>Conclusions: </strong>Fixed pyrazinamide doses of 1500, 1750, and 2000 mg are recommended for patients weighing 40-70, 70-80, and 80-90 kg, respectively, to achieve the exposure targets of AUC0-24 > 363 mg·h/L or Cmax > 35 mg/L to attain efficacy.</p>","PeriodicalId":23052,"journal":{"name":"Therapeutic Drug Monitoring","volume":null,"pages":null},"PeriodicalIF":2.8,"publicationDate":"2024-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142143380","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}
Dario Cattaneo, Anna Lisa Ridolfo, Andrea Giacomelli, Antonella Castagna, Alberto Dolci, Spinello Antinori, Cristina Gervasoni
{"title":"The Case of Dolutegravir Plus Darunavir Antiretroviral Regimens: Is It Always Useful to Double the Drug Doses? A Short Communication.","authors":"Dario Cattaneo, Anna Lisa Ridolfo, Andrea Giacomelli, Antonella Castagna, Alberto Dolci, Spinello Antinori, Cristina Gervasoni","doi":"10.1097/FTD.0000000000001259","DOIUrl":"https://doi.org/10.1097/FTD.0000000000001259","url":null,"abstract":"<p><strong>Background: </strong>Antiretroviral drug combinations affect dolutegravir trough concentrations. Here, the authors focused on dolutegravir plus booster darunavir antiretroviral regimens to investigate the effect of the booster and/or timing of drug administration on dolutegravir and darunavir plasma trough concentrations.</p><p><strong>Methods: </strong>This retrospective observational study included consecutive people with HIV (PWH) receiving dolutegravir plus booster darunavir antiretroviral regimens for at least 3 months, with at least one assessment of dolutegravir and darunavir plasma trough concentrations.</p><p><strong>Results: </strong>A total of 200 drug therapeutic drug monitoring results from 116 PWH were included. Dolutegravir and darunavir trough concentrations ranged, respectively, from 70 to 3648 mcg/L and from 102 to 11,876 mcg/L. The antiretroviral drug combination associated with the highest dolutegravir trough concentration was dolutegravir plus darunavir/cobicistat, both once daily (1410 ± 788 mcg/L), whereas dolutegravir once daily plus darunavir/ritonavir twice daily had the lowest trough concentrations (686 ± 481 mcg/L). Doubling the dose of dolutegravir did not significantly increase drug trough concentrations compared with that of once-daily regimens. Instead, the highest darunavir trough concentrations were with ritonavir (2850 ± 1456 mcg/L, P < 0.05 versus cobicistat-based regimens). Doubling the drug dose resulted in a significant increase in the darunavir trough concentration (4445 ± 2926 mcg/L, P < 0.05).</p><p><strong>Conclusions: </strong>Dolutegravir trough concentrations were significantly reduced in PWH receiving darunavir/ritonavir twice daily. This evidence should be carefully considered in clinical conditions requiring higher dolutegravir exposure, such as in the presence of drug-drug interactions with drugs known to reduce dolutegravir bioavailability or in highly experienced PWH.</p>","PeriodicalId":23052,"journal":{"name":"Therapeutic Drug Monitoring","volume":null,"pages":null},"PeriodicalIF":2.8,"publicationDate":"2024-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142133835","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":"Pharmacokinetic and Pharmacodynamic Assessment of Valganciclovir in Infants With Congenital Cytomegalovirus Infection.","authors":"Kotaro Itohara, Kazuhiro Yamamoto, Shunsuke Fujinaka, Mari Hashimoto, Naoki Tamura, Yumi Kitahiro, Tomohiro Omura, Kazumichi Fujioka, Ikuko Yano","doi":"10.1097/FTD.0000000000001257","DOIUrl":"https://doi.org/10.1097/FTD.0000000000001257","url":null,"abstract":"<p><strong>Background: </strong>Valganciclovir (VGCV) is administered at a dose of 16 mg/kg 2 times daily for 6 months to treat symptomatic congenital cytomegalovirus (CMV) infections. During the treatment period, approximately 20% of the patients developed grade 3 or higher neutropenia. Currently, information on the pharmacokinetics and pharmacodynamics of ganciclovir, an active metabolite of VGCV, in infants is limited. In the current study, the relationship between ganciclovir concentration and neutropenia was investigated, and a population pharmacokinetic (PPK) model of ganciclovir in infants with symptomatic congenital CMV infection was developed.</p><p><strong>Methods: </strong>Japanese infants who were prescribed oral VGCV for symptomatic congenital CMV infections between July 2017 and January 2021 were included. The relationship between the observed trough ganciclovir concentrations and neutrophil counts was examined. PPK analysis was performed to evaluate the covariates affecting the pharmacokinetics of ganciclovir.</p><p><strong>Results: </strong>Twenty-seven ganciclovir serum samples from 8 patients were analyzed. A moderate negative correlation was observed between the observed trough ganciclovir concentration and neutrophil count. PPK model analysis showed that postmenstrual age (PMA) affected the total body clearance of ganciclovir after correcting for the empirical allometric scaling of body weight. Based on PMA and body weight, a nomogram to achieve the target area under the concentration-time curve from 0 to 24 hours of 40-60 mcg·h·mL-1 of ganciclovir was calculated.</p><p><strong>Conclusions: </strong>The relationship between neutrophil count and ganciclovir trough concentration in infants was clarified. The PPK model showed that the dose of VGCV should be reduced in patients with a low PMA to achieve target exposure.</p>","PeriodicalId":23052,"journal":{"name":"Therapeutic Drug Monitoring","volume":null,"pages":null},"PeriodicalIF":2.8,"publicationDate":"2024-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142296136","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":"Association of Plasma Cabozantinib Concentration With Treatment Response and Adverse Events in Japanese Patients With Advanced Renal Cell Carcinoma.","authors":"Shinichi Maruyama, Hiroaki Kobayashi, Tatsuru Hiraga, Tadatsugu Anno, Tansei Sanjo, Masashi Arai, Masaru Ishida, Hiroshi Kanno, Masaru Kato","doi":"10.1097/FTD.0000000000001254","DOIUrl":"https://doi.org/10.1097/FTD.0000000000001254","url":null,"abstract":"<p><strong>Background: </strong>Cabozantinib is highly effective against advanced renal cell carcinoma (RCC). However, approximately 60% of the patients require a dose reduction due to severe adverse events. Although associations between trough concentrations of cabozantinib and its efficacy and safety have been reported in other countries, reports on Japanese patients are unavailable. Therefore, we investigated the association of cabozantinib trough concentration with therapeutic efficacy and adverse events in Japanese patients with RCC and evaluated the usefulness of therapeutic drug monitoring.</p><p><strong>Methods: </strong>In this prospective observational study, we measured the trough concentrations of cabozantinib in 10 Japanese patients with RCC enrolled between May 2022 and September 2023. The associations of trough concentration with treatment response, as determined by RECIST 1.1, and the occurrence of grade 2 or higher adverse events were assessed.</p><p><strong>Results: </strong>Trough concentration was higher in patients with controlled cancer than in those with progressive cancer (1024 ± 352 versus 457 ± 216 ng/mL, P = 0.035). In addition, patients with grade 2 or higher adverse events showed a significantly higher trough concentration than those without (1560 ± 513 versus 807 ± 319 ng/mL, P = 0.032). In particular, grade 2 or higher dysgeusia, anorexia, fatigue, and dyspepsia significantly correlated with trough concentrations.</p><p><strong>Conclusions: </strong>This is the first clinical study to demonstrate a correlation between cabozantinib trough concentration, therapeutic efficacy, and adverse events in Japanese patients with RCC. The therapeutic drug monitoring of cabozantinib could be useful for improving therapeutic efficacy and avoiding serious adverse events.</p>","PeriodicalId":23052,"journal":{"name":"Therapeutic Drug Monitoring","volume":null,"pages":null},"PeriodicalIF":2.8,"publicationDate":"2024-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142112233","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}
Steffie E M Vonk, Marloes van der Meer-Vos, Renate Kos, Anne H Neerincx, Suzanne W J Terheggen-Lagro, Josje Altenburg, Anke H Maitland-van der Zee, Ron A A Mathôt, E Marleen Kemper
{"title":"Dried Blood Spot Method Development and Clinical Validation for the Analysis of Elexacaftor, Elexacaftor-M23, Tezacaftor, Tezacaftor-M1, Ivacaftor, Ivacaftor Carboxylate, and Hydroxymethyl Ivacaftor Using LC-MS/MS.","authors":"Steffie E M Vonk, Marloes van der Meer-Vos, Renate Kos, Anne H Neerincx, Suzanne W J Terheggen-Lagro, Josje Altenburg, Anke H Maitland-van der Zee, Ron A A Mathôt, E Marleen Kemper","doi":"10.1097/FTD.0000000000001231","DOIUrl":"10.1097/FTD.0000000000001231","url":null,"abstract":"<p><strong>Background: </strong>The highly effective Cystic Fibrosis Transmembrane conductance Regulator (CFTR) modulator, elexacaftor-tezacaftor-ivacaftor, is now widely being used by people with cystic fibrosis. However, few independent studies have detailed the pharmacokinetics (PK) of CFTR modulators. Blood collection by venipuncture is the gold standard for PK measurements, but it is invasive. The aim of this study was to develop and clinically validate a quantification method for elexacaftor, tezacaftor, ivacaftor, and their main metabolites in dried blood spots (DBSs) using liquid chromatography with tandem mass spectrometry.</p><p><strong>Methods: </strong>Linearity, accuracy, precision, stability, hematocrit (Hct), spot-to-spot carryover, spot volume, and extraction efficiency were validated in DBS for all analytes. The clinical validation of elexacaftor-tezacaftor-ivacaftor in patients was performed by comparing 21 DBS samples with matched plasma samples.</p><p><strong>Results: </strong>The preset requirements for linearity, within-run and between-run accuracy, precision, Hct, spot volume, and extraction efficiency were met. Puncher carryover was observed and resolved by punching 3 blanks after each sample. The samples remained stable and showed no notable degradation across the tested temperatures and time intervals. Corrected DBS values with the Passing-Bablok regression equation showed good agreement in Bland-Altman plots, and acceptance values were within 20% of the mean for a minimum of 67% of the repeats, according to the EMA guidelines.</p><p><strong>Conclusions: </strong>A quantification method for the analysis of elexacaftor, tezacaftor, ivacaftor, and their main metabolites was developed and clinically validated in DBS. This method could be valuable in both clinical care and research to address unanswered PK questions regarding CFTR modulators.</p>","PeriodicalId":23052,"journal":{"name":"Therapeutic Drug Monitoring","volume":null,"pages":null},"PeriodicalIF":2.8,"publicationDate":"2024-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141459470","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}