European Journal of Drug Metabolism and Pharmacokinetics最新文献

{"title":"Mass Balance Recovery, Absorption, Metabolism, and Excretion of Elinzanetant in Healthy Human Volunteers and in vitro Biotransformation.","authors":"Simone I Schulz, Marcus-Hillert Schultze-Mosgau, Anna Engelen, Nand Singh, Steve Pawsey, Klaus Francke, Ruth Lock, Antje Rottmann","doi":"10.1007/s13318-024-00930-3","DOIUrl":"10.1007/s13318-024-00930-3","url":null,"abstract":"<p><strong>Background: </strong>Elinzanetant is a dual neurokinin-1,3 receptor antagonist in development for the treatment of menopausal vasomotor symptoms. The objectives of these studies were to characterize the mass balance and biotransformation of elinzanetant.</p><p><strong>Methods: </strong>In the clinical evaluation, whole blood, plasma, urine, and feces were collected from healthy fasted male volunteers (n = 6) following a single dose of 120 mg [¹⁴C]-elinzanetant oral suspension for analysis of total radioactivity and metabolite profiling. In vitro reaction phenotyping and kinetics experiments on enzymes involved in elinzanetant metabolism were performed.</p><p><strong>Results: </strong>On average, 90.8% of the total radioactivity administered was recovered in excreta over 480 h, mostly via the fecal route (feces 90.4%; urine 0.4%). Elinzanetant was rapidly absorbed and extensively metabolized but remained the main circulating species in plasma, accounting for 39.1% of total radioactivity. Known principal and active metabolites M27, M30/34, and M18/21 accounted for 7.6%, 13.7%, and 4.9% of total radioactivity in plasma, respectively. All other radiolabeled plasma components were each < 3.5%, revealing the oxidation product M30/34 as the only metabolite with relevant exposure (> 10% of total radioactivity). In feces, metabolites resulting from oxidative biotransformation accounted, in sum, for ~ 40% of the dose, while elinzanetant remained the primary drug-related moiety. Results of in vitro experiments indicated that metabolism of elinzanetant was primarily mediated by cytochrome P450 3A4, with minor contribution from uridine 5'-diphospho-glucuronosyltransferase.</p><p><strong>Conclusions: </strong>Elinzanetant is metabolized mainly via oxidative biotransformation mediated by cytochrome P450 3A4, and primarily excreted in feces. The primary oxidation product M30/34 is a major human metabolite of elinzanetant.</p><p><strong>Trial registration number: </strong>NCT04654897.</p>","PeriodicalId":11939,"journal":{"name":"European Journal of Drug Metabolism and Pharmacokinetics","volume":" ","pages":"91-103"},"PeriodicalIF":1.9,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11802607/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142885274","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Physiologically-Based Pharmacokinetic Modeling of Trofinetide in Moderate Renal Impairment for Phase 1 Clinical Study Dose Selection with Model Validation.","authors":"Mona Darwish, Thomas C Marbury, Rene Nunez, James M Youakim, Di An, Inger Darling, Viera Lukacova, Kathie M Bishop","doi":"10.1007/s13318-024-00924-1","DOIUrl":"10.1007/s13318-024-00924-1","url":null,"abstract":"<p><strong>Background and objectives: </strong>Trofinetide, the first approved treatment for Rett syndrome (RTT), is primarily excreted unchanged in the urine; therefore, it is important to assess the extent to which the exposure is affected in patients with renal impairment. Pharmacokinetic modeling overcomes the challenge of dose finding in phase 1 studies that include special populations where there is the potential for increased exposure to study drug. The objectives of this phase 1 study were to evaluate trofinetide pharmacokinetics, safety, and tolerability in a population with moderate renal impairment and normal renal function. The observed pharmacokinetic profiles were used to validate the dosing adjustments in moderate renal impairment that were previously predicted using a physiologically-based pharmacokinetic (PBPK) model.</p><p><strong>Methods: </strong>The PBPK model was first used to predict dose adjustments that are necessary to achieve similar exposure in the four stages of renal impairment (mild, moderate, severe, end stage renal disease) as in healthy controls. The predicted dose adjustment from 12 to 6 g for the moderate renal impairment category was then applied to the phase 1 clinical study. Subsequent validation of the PBPK model was achieved by comparing the model-predicted and clinically observed exposures in subjects with moderate renal impairment. In a phase 1, open-label study, trofinetide exposure was assessed in healthy (n = 10) and moderate renal impairment (n = 10) participants receiving single oral doses of 12 g or 6 g, respectively. Observed exposures [area under the blood concentration-time curve from time 0 to infinity (AUC_inf) and maximum concentration (C_max)] were compared with predicted exposures from simulations in virtual healthy and moderate renal impairment populations (n = 100) to validate a PBPK model of renal impairment that had previously predicted doses across renal impairment categories.</p><p><strong>Results: </strong>Dose-normalized geometric mean ratios for C_max were comparable [1.02 (90% CI 0.69-1.50)] while AUC_inf was approximately two-fold higher [1.81 (90% CI 1.31-2.50)] in moderate renal impairment participants compared with healthy controls. These observed values closely aligned with predicted distributions. Treatment-emergent adverse events were reported in two (20.0%) participants with moderate renal impairment and four healthy participants (40.0%).</p><p><strong>Conclusion: </strong>PBPK modeling of trofinetide in a virtual population with moderate renal impairment predicted a 50% dose reduction compared to individuals with normal renal function. Comparison of observed pharmacokinetic results from a phase 1 study in subjects with moderate renal impairment and matched healthy participants to the model-predicted exposures validated this dose reduction. No new safety concerns for trofinetide emerged.</p>","PeriodicalId":11939,"journal":{"name":"European Journal of Drug Metabolism and Pharmacokinetics","volume":" ","pages":"23-38"},"PeriodicalIF":1.9,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11802684/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142617149","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An Exploration of the Interplay Between Caffeine and Antidepressants Through the Lens of Pharmacokinetics and Pharmacodynamics.","authors":"Jenny Truong, Noor Abu-Suriya, Daniel Tory, Rita Bahho, Audrey Ismaiel, Thach Nguyen, Angela Mansour, Varsha Nand, Julijana Saponja, Kamal Dua, Gabriele De Rubis, Daniele Parisi","doi":"10.1007/s13318-024-00928-x","DOIUrl":"10.1007/s13318-024-00928-x","url":null,"abstract":"<p><p>Caffeine consumption is regarded as a widespread phenomenon, and its usage has continued to increase. In addition, the growing usage of antidepressants worldwide and increase in mental health disorders were shown in recent statistical analyses conducted by the World Health Organisation. The coadministration of caffeine and antidepressants remains a concern due to potential interactions that can alter a patient's response to therapy. This review investigates the pharmacokinetic and pharmacodynamic interactions between caffeine and the five main classes of antidepressants: selective serotonin reuptake inhibitors (SSRIs), tricyclic antidepressants (TCAs), serotonin and norepinephrine reuptake inhibitors (SNRIs), monoamine oxidase inhibitors (MAOIs), and other antidepressants not categorised by class, which we have categorised as 'miscellaneous'. The interaction between fluvoxamine and caffeine resulted in increased concentrations of caffeine in the body and lowered the renal clearance of fluvoxamine. Other SSRIs such as fluoxetine and escitalopram had augmented antidepressant effects by decreasing their renal clearance and prolonging their effects in the body when coadministered with caffeine. Caffeine may also increase the concentration of paroxetine, potentially affecting its pharmacodynamic effects. TCAs such as clomipramine, imipramine, desipramine, and sertraline, were found to reduce the metabolism of caffeine. However, studies suggest caffeine had no significant effect on the concentration of these medications in blood or brain tissue. The inhibition of caffeine at high doses when used with MAOIs such as tranylcypromine and phenelzine was found to lead to a higher likelihood of experiencing hypertension. Coadministration of caffeine with venlafaxine (SNRIs) suggests minimal interactions between the two substances and the pharmacodynamic effects of venlafaxine were unlikely to be impacted by caffeine consumption. Miscellaneous antidepressants (reboxetine, mianserin, agomelatine, maprotiline, and mirtazapine) displayed varying pharmacodynamic interactions with caffeine, resulting in increased antidepressant effects where vortioxetine, maprotiline, and mirtazapine failed to demonstrate any interactions. In conclusion, caffeine demonstrated varying effects on the pharmacokinetic and pharmacodynamic properties of each class of antidepressants, with several classes of antidepressants demonstrating a similar effect on caffeine.</p>","PeriodicalId":11939,"journal":{"name":"European Journal of Drug Metabolism and Pharmacokinetics","volume":" ","pages":"1-15"},"PeriodicalIF":1.9,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11802704/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143051929","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Loss-of-Function ATP Binding Cassette Subfamily G Member 2 Polymorphism ABCG2 c.421C>A Reduces Lamotrigine Trough Concentrations in Adults with Epilepsy.","authors":"Nada Božina, Iva Klarica Domjanović, Ivana Šušak Sporiš, Lana Ganoci, Mila Lovrić, Vladimir Trkulja","doi":"10.1007/s13318-024-00925-0","DOIUrl":"10.1007/s13318-024-00925-0","url":null,"abstract":"<p><strong>Background and objectives: </strong>The commonly used antiseizure medication lamotrigine is a substrate to ATP binding cassette subfamily G member 2 (ABCG2) transporter. The objective of this study was to evaluate the effect of the common loss-of-function polymorphism ABCG2 c.421C>A (rs2231142) on the lamotrigine trough concentrations at steady state in adults with epilepsy.</p><p><strong>Methods: </strong>In two consecutive studies (Study 1, Study 2) in patients on lamotrigine monotherapy, carriers of the variant ABCG2 c.421C>A allele (CA/AA) were considered exposed, and wild-type homozygotes (CC) were considered controls. They were mutually balanced on covariates (age, sex, body weight, several polymorphisms in genes encoding other transporter proteins and lamotrigine-metabolizing enzymes that have been suggested to affect exposure to lamotrigine) to estimate the exposure effect (geometric means ratios, GMRs) in each study separately and overall (individual patient data meta-analysis). The overall estimate was evaluated for sensitivity to residual confounding.</p><p><strong>Results: </strong>In both studies (exposed n = 28 vs. controls n = 103; exposed n = 44 vs. controls n = 153, in Study 1 and Study 2, respectively) and overall (exposed n = 72 vs. controls n = 256), dose-corrected lamotrigine trough concentrations were moderately lower in the exposed patients: frequentist GMR [95% CI] = 0.82 [0.63-1.08]; GMR = 0.69 [0.60-0.81] and GMR = 0.72 [0.63-0.83] in Study 1, Study 2 and overall, respectively; Bayes GMR [95% CrI] = 0.83 [0.68-1.00]; GMR = 0.69 [0.58-0.83] and GMR = 0.75 [0.65-0.86] in Study 1, Study 2 and overall, respectively. Estimates appeared resistant to unmeasured confounding-the E-values for the pooled point estimates were high, and estimates corrected for a strong hypothetical bias were GMR = 0.78 [0.68-0.90] frequentist and GMR = 0.81 [0.70-0.93] Bayes.</p><p><strong>Conclusion: </strong>Polymorphism ABCG2 c.421C>A moderately reduces lamotrigine concentrations in adults with epilepsy.</p>","PeriodicalId":11939,"journal":{"name":"European Journal of Drug Metabolism and Pharmacokinetics","volume":" ","pages":"17-22"},"PeriodicalIF":1.9,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142562568","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":"Determination of Intrinsic Clearance and Fraction Unbound in Human Liver Microsomes and In Vitro-In Vivo Extrapolation of Human Hepatic Clearance for Marketed Central Nervous System Drugs.","authors":"Veera Raghava Chowdary Palacharla, Ramakrishna Nirogi, Nitesh Kumar, Krishnadas Nandakumar","doi":"10.1007/s13318-024-00931-2","DOIUrl":"10.1007/s13318-024-00931-2","url":null,"abstract":"<p><strong>Objective: </strong>The objective of this study was to determine the apparent intrinsic clearance (Cl_{int, app}) and fraction unbound in human liver microsomes (f_{u, mic}) of 86 marketed central nervous system (CNS) drugs and to predict the in vivo hepatic blood clearance (CL_{h, b}).</p><p><strong>Methods: </strong>Cl_{int, app} in human liver microsomes (HLM) was determined by substrate depletion, and f_{u, mic} was determined by equilibrium dialysis. The relationship between lipophilicity (logP) and unbound intrinsic clearance (Cl_{int, u}) was explored using the Biopharmaceutical Drug Disposition Classification System (BDDCS) and Extended Clearance Classification System (ECCS). The predicted hepatic blood clearance by direct scaling, conventional method and Poulin method using well-stirred (WS) and parallel-tube (PT) models were compared with observed values.</p><p><strong>Results: </strong>The Cl_{int, app} in HLM ranged from < 5.8 to 477 µl/min/mg. The f_{u, mic} in HLM ranged from 0.02 to 1.0. The scaled Cl_int values ranged from < 5 to 4496 ml/min/kg. The metabolic rate increased with an increase in logP (logP ≥ 2.5) of the CNS compounds. The direct scaling and Poulin methods showed comparable results based on the percentage of clearance predictions within a two-fold error. The conventional method resulted in under-predictions of Cl_{int, in vivo} or CL_{h, b} using the WS or PT models. The Poulin method is favored over the other methods based on the statistical parameters.</p><p><strong>Conclusions: </strong>Experimental Cl_{int, app} and f_{u, mic} for 86 CNS compounds were successfully determined, and the scaled clearance was used to predict the hepatic blood clearance of 34 drugs. The success of prospective clearance predictions using HLM is expected to be high for most of the lipophilic BDDCS class 1 and class 2 and ECCS class 2 CNS compounds. The Poulin method resulted in more accurate predictions falling within a two-fold error of the observed values using the WS or PT models.</p>","PeriodicalId":11939,"journal":{"name":"European Journal of Drug Metabolism and Pharmacokinetics","volume":" ","pages":""},"PeriodicalIF":1.9,"publicationDate":"2024-12-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142893180","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":"Prediction of First-in-Human Dose of Chimeric Antigen Receptor-T (CAR-T) Cells from Mice.","authors":"Iftekhar Mahmood","doi":"10.1007/s13318-024-00918-z","DOIUrl":"10.1007/s13318-024-00918-z","url":null,"abstract":"<p><p>BACKGROUND AND OBJECTIVE: Currently, there is no available method for the prediction of first-in-human (FIH) dose for chimeric antigen receptor-T (CAR-T) cells. The objective of this work was to predict the FIH dose of CAR-T cells from different doses given to mice.</p><p><strong>Methods: </strong>In this study, six scaling methods were evaluated for the prediction of FIH dose for CAR-T cells. The methods were body weight-based fixed exponents such as 1.0 and 0.75, human equivalent dose (HED) using exponents 0.33, two modified HED methods such as using total animal dose (in place of per kg basis) and body surface area in place of body weight using total animal dose with exponent 0.33 and a physiological factor derived from physiological parameters. The FIH doses of six CAR-T cells were predicted in this study. The predicted human doses were compared with the recommended human dose by the US-FDA for four CAR-T cell products, and the literature data were used for the remaining two CAR-T cells.</p><p><strong>Results: </strong>The results indicated that the two modified HED methods and physiological factor are the best and reliable methods for the prediction of FIH dose for CAR-T cells.</p><p><strong>Conclusions: </strong>The proposed methods are simple and accurate in their predictive power and can be used on a spreadsheet.</p>","PeriodicalId":11939,"journal":{"name":"European Journal of Drug Metabolism and Pharmacokinetics","volume":" ","pages":"715-722"},"PeriodicalIF":1.9,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142282415","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":"Comparison of Vancomycin AUC24 Calculation Methods for Neonates and Infants.","authors":"Tuomas Laitila, Ulla Sankilampi, Marjo Renko, Merja Kokki, Veli-Pekka Ranta","doi":"10.1007/s13318-024-00920-5","DOIUrl":"10.1007/s13318-024-00920-5","url":null,"abstract":"<p><strong>Background and objective: </strong>For neonates and infants receiving intermittent vancomycin infusions, the area under the concentration-time curve during 24 h (AUC24) is often estimated with Bayesian forecasting using one or more measured vancomycin concentrations. When practical peak and trough concentrations are measured at steady state, AUC24 can also be calculated with first-order steady-state equations for a one-compartment model (Sawchuk-Zaske method), but previously this method has been applied only for adults. The objective of this study was to compare AUC24 values obtained with the Sawchuk-Zaske method and two Bayesian models.</p><p><strong>Methods: </strong>AUC24 values were estimated retrospectively for 18 neonates and infants with steady-state peak and trough concentrations using traditional compartmental analysis with a one-compartment model (reference method), the Sawchuk-Zaske method, and Bayesian forecasting with two previously published models. In Bayesian forecasting, both original and modified residual error models were used. In the modified models, the residual error was reduced by setting the additive residual error to zero and the proportional error to 15%.</p><p><strong>Results: </strong>AUC24 estimates obtained with the Sawchuk-Zaske method differed - 2.7 to 0.9% from the reference method. When both peak and trough concentrations were used in Bayesian forecasting, 61% and 33% of AUC24 estimates obtained with two original models differed less than 15% from the reference method, and these fractions increased to 83% and 72% with the modified models, respectively.</p><p><strong>Conclusion: </strong>When practical peak and trough concentrations are measured at steady state, the simple Sawchuk-Zaske method is very useful for AUC24 estimation in neonates and infants. In Bayesian forecasting, the reduced residual error model can be used to improve the model fit.</p>","PeriodicalId":11939,"journal":{"name":"European Journal of Drug Metabolism and Pharmacokinetics","volume":" ","pages":"773-779"},"PeriodicalIF":1.9,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11549144/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142497388","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Pharmacokinetic Model of Drug Interaction of Tacrolimus with Combined Administration of CYP3A4 Inhibitors Voriconazole and Clarithromycin After Bone Marrow Transplantation.","authors":"Toshinori Hirai, Takahiko Aoyama, Yasuhiro Tsuji, Kazuko Ino, Makoto Ikejiri, Isao Tawara, Takuya Iwamoto","doi":"10.1007/s13318-024-00915-2","DOIUrl":"10.1007/s13318-024-00915-2","url":null,"abstract":"<p><strong>Background and objectives: </strong>A pharmacokinetic model has been developed to quantify the drug-drug interactions of tacrolimus with concentration-dependent inhibition of cytochrome P450 (CYP) 3A4 from voriconazole and clarithromycin based on the CYP3A5 and CYP2C19 genotypes.</p><p><strong>Methods: </strong>This retrospective study recruited unrelated bone marrow transplant recipients receiving oral tacrolimus concomitantly with voriconazole and clarithromycin. The published population pharmacokinetic model that implemented genotypes of CYP3A5 (tacrolimus) and CYP2C19 (voriconazole) was integrated. The tested CYP3A4 inhibition models (Sigmoid efficacy maximum [E_max], E_max, log-linear, and linear) were a function of competitive inhibition of voriconazole and mechanism-based inhibition of clarithromycin in a virtual enzyme compartment.</p><p><strong>Results: </strong>The total tacrolimus trough concentrations were 119 points, with a median of 4.3 (range: 2.0-9.9) ng/mL (n = 3). The final model comprised the Sigmoid E_max model for voriconazole and clarithromycin, which depicted time-course alterations in tacrolimus concentration and clearance when given voriconazole and clarithromycin.</p><p><strong>Conclusions: </strong>These findings could facilitate the model-informed precision dosing of tacrolimus after unrelated bone marrow transplant.</p>","PeriodicalId":11939,"journal":{"name":"European Journal of Drug Metabolism and Pharmacokinetics","volume":" ","pages":"763-771"},"PeriodicalIF":1.9,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142307359","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":"Does Age Influence Immunosuppressant Drug Pharmacokinetics in Kidney Transplant Recipients?","authors":"Amelia R Cossart, Nicole M Isbel, Scott B Campbell, Brett McWhinney, Christine E Staatz","doi":"10.1007/s13318-024-00914-3","DOIUrl":"10.1007/s13318-024-00914-3","url":null,"abstract":"<p><strong>Background: </strong>The pharmacokinetics of immunosuppressant drugs may change with advancing age, potentially affecting patient outcomes.</p><p><strong>Objective: </strong>To characterise the effects of age on the pharmacokinetic and exposure parameters of tacrolimus, mycophenolate, and prednisolone.</p><p><strong>Methods: </strong>Pharmacokinetic profiling, involving whole blood tacrolimus, total and free plasma mycophenolic acid (MPA), total plasma mycophenolic acid glucuronide (MPAG), and total and free plasma prednisolone, was performed in an older and younger adult cohort. Thirteen samples were drawn on a single occasion, pre-oral dose and then at 0.25, 0.5, 0.75, 1, 1.25, 1.5, 2, 3, 4, 6, 9, and 12 h post-dose. Non-compartmental analysis was conducted using the PKNCA package, and pharmacokinetic and exposure parameters were compared between age groups using a Mann-Whitney test. A regression analysis was conducted for free MPA and MPAG using significant variables of interest.</p><p><strong>Results: </strong>This exploratory study included 21 older and 18 younger adults. Dose-adjusted tacrolimus, total MPA and free prednisolone pharmacokinetic parameters were not different between age groups; however, for free MPA and MPAG, older recipients had significantly greater minimum and maximum concentrations, trough concentrations, and half-life. There was a two-fold increase in free MPA exposure in older adults (median dose-adjusted AUC_0-12: 1284 vs. 684 μg h/L, p < 0.0001); MPAG exposure similarly increased. Age was significantly associated with free MPA and MPAG exposure, and free MPA exposure was associated with haematocrit (p < 0.05).</p><p><strong>Conclusion: </strong>Differences in MPA were found with advancing age and may be due to altered kidney function, haematocrit, plasma protein binding and/or drug absorption. Future research should explore specific covariate contributions to this further.</p>","PeriodicalId":11939,"journal":{"name":"European Journal of Drug Metabolism and Pharmacokinetics","volume":" ","pages":"751-761"},"PeriodicalIF":1.9,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11549176/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142105655","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Pharmacokinetic and Pharmacodynamic Interaction of Finerenone with Diltiazem, Fluconazole, and Ritonavir in Rats.","authors":"Tham Thi Bui, So-Hyeon Kim, Woojin Jung, Sung-Yoon Yang, Quyen Thi Tran, Hyunjung Lee, Seongwon Park, Lien Thi Ngo, Hwi-Yeol Yun, Jung-Woo Chae","doi":"10.1007/s13318-024-00917-0","DOIUrl":"10.1007/s13318-024-00917-0","url":null,"abstract":"<p><strong>Background and objectives: </strong>Finerenone, a novel selective non-steroidal mineralocorticoid receptor antagonist, has been indicated in chronic kidney disease associated with type 2 diabetes mellitus. Considering the potential complications of diabetes, finerenone can be co-administered with various drugs, including fluconazole, diltiazem, and ritonavir. Given that finerenone is a substrate of cytochrome P450 (CYP) 3A4, the concurrent administration of finerenone with CYP3A4 inhibitors (diltiazem or fluconazole or ritonavir) could potentially lead to drug interactions, which may cause adverse events such as hyperkalemia. No studies have investigated interactions between finerenone and diltiazem or fluconazole or ritonavir. Therefore, this study aims to investigate the pharmacokinetic interaction of finerenone with diltiazem or fluconazole or ritonavir and to evaluate the impact of fluconazole on the pharmacodynamics of finerenone.</p><p><strong>Methods: </strong>The pharmacokinetic study included four rat groups (n = 8 rats/group), including a control group (finerenone alone) and test groups (finerenone pretreated with diltiazem or fluconazole or ritonavir) using both non-compartment analysis (NCA) and population pharmacokinetic (pop-PK) modeling. The pop-PK model was developed using non-linear mixed-effects modeling in NONMEM^® (version 7.5.0). In the pharmacodynamic study, serum potassium (K⁺) levels were measured to assess the effects of fluconazole on finerenone-induced hyperkalemia.</p><p><strong>Results: </strong>The NCA results indicated that the area under the plasma concentration-time curve (AUC) of finerenone increased by 1.86- and 1.95-fold when coadministered with fluconazole and ritonavir, respectively. In contrast, diltiazem did not affect the pharmacokinetics of finerenone. The pharmacokinetic profiles of finerenone were best described by a one-compartment disposition with first-order elimination and dual first-order absorption kinetics. The pop-PK modeling results demonstrated that the apparent clearance of finerenone decreased by 50.3% and 49.2% owing to the effects of fluconazole and ritonavir, respectively. Additionally, the slow absorption rate, which represents the absorption in the distal intestinal tract of finerenone, increased by 55.7% due to the effect of ritonavir. Simultaneously, a pharmacodynamic study revealed that finerenone in the presence of fluconazole caused a significant increase in K⁺ levels compared with finerenone alone.</p><p><strong>Conclusions: </strong>Coadministration of finerenone with fluconazole or ritonavir increased finerenone exposure in rats. Additionally, the administration of finerenone in the presence of fluconazole resulted in elevated K⁺ levels in rats. Further clinical studies are required to validate these findings.</p>","PeriodicalId":11939,"journal":{"name":"European Journal of Drug Metabolism and Pharmacokinetics","volume":" ","pages":"701-714"},"PeriodicalIF":1.9,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142282414","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}