Dustri Online Services

Search Results

Books: 0	Journals: 1	Articles: 2

Original Research

Evaluation of intravenous midazolam limited sampling models to determine area under the concentration time curve during cytochrome P450 3A baseline, inhibition and induction or activation

Anh N. Nguyen, Justin T. Hoffman, Shirley M. Tsunoda, In-Jin Jang and Joseph D. Ma

Price
42.00 $

Add to Cart

Price

42.00 $

Volume 50 p. 468 - 475

Abstract

International Journal of Clinical Pharmacology and Therapeutics, Vol. 50 – No. 7/2012 (468-475)

Evaluation of intravenous midazolam limited sampling models to determine area under the concentration time curve during cytochrome P450 3A baseline, inhibition and induction or activation

Anh N. Nguyen¹, Justin T. Hoffman¹, Shirley M. Tsunoda¹, In-Jin Jang² and Joseph D. Ma¹

¹University of California, San Diego (UCSD), Skaggs School of Pharmacy and Pharmaceutical Sciences, La Jolla, CA, USA, and ²Seoul National University College of Medicine, Seoul, South Korea
Objective: This study evaluated if previously published limited sampling models (LSMs) accurately predict midazolam area under the concentration time curve (AUC) during cytochrome P450 (CYP) 3A baseline, inhibition and induction/activation. Materials and methods: Plasma midazolam concentrations (n = 108) were obtained where intravenous midazolam was co-administered alone or concomitantly with ketoconazole, itraconazole, aprepitant, rifampin, or pleconaril. Observed AUC was calculated using noncompartmental analysis. Predicted AUC was calculated from the LSMs. Bias and precision were determined by percent mean prediction error (%MPE), percent mean absolute error (%MAE), and percent root mean squared error (%RMSE). Results: Contrasting results were observed for LSMs in predicting CYP3A baseline activity, with the majority of studies resulting in unacceptable bias and precision. During CYP3A inhibition, unacceptable bias and precision were observed from single- and 2-time point LSMs. %MAE and %RMSE values exceeded acceptable limits during CYP3A induction with rifampin. Contrasting results were observed with pleconaril. Conclusion: The contrasting results during CYP3A baseline and induction/activation, as well as the unacceptable bias and precision during CYP3A inhibition, limits the widespread use of the previously published LSMs.Correspondence to:
Joseph D. Ma, PharmD, UCSD
Skaggs School of Pharmacy and Pharmaceutical Sciences
9500 Gilman Drive, MC 0714
La Jolla, CA 92093, USA
Email: [email protected]

Original

Limitations of fexofenadine limited sampling strategy using plasma concentrations and partial area under the concentration-time curve to estimate transporter activity in healthy adults 

Marlon Liyanage, Chelsea L. Blaquera, Joseph Piscitelli, Scott R. Penzak, Thomas D. Nolin, Mary F. Paine, and Joseph D. Ma

Price
42.00 $

Add to Cart

Price

42.00 $

Volume 61 (2023) p. 262 - 269

Abstract

International Journal of Clinical Pharmacology and Therapeutics, Vol. 61 – No. 6/2023 (262-269)

Limitations of fexofenadine limited sampling strategy using plasma concentrations and partial area under the concentration-time curve to estimate transporter activity in healthy adults 

Marlon Liyanage¹, Chelsea L. Blaquera¹, Joseph Piscitelli¹, Scott R. Penzak², Thomas D. Nolin³, Mary F. Paine⁴, Joseph D. Ma¹ 

¹Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, CA, ²Harrison School of Pharmacy, Auburn University, Auburn, AL, ³University of Pittsburgh School of Pharmacy, Pittsburgh, PA, and ⁴College of Pharmacy & Pharmaceutical Sciences, Washington State University, Spokane, WA, USA
Objective: Fexofenadine is a probe drug used to phenotype P-glycoprotein (P-gp) and organic anion transporting polypeptide (OATP) 1B1/3 activities. This study evaluated a limited sampling strategy using plasma concentrations and/or partial area under the concentration versus time curves (AUCs) to estimate systemic exposure and, potentially, P-gp and OATP1B1/3 activities.
Materials and methods: Plasma concentration versus time data were obtained from 53 healthy adult participants (22 females) from four published studies. Participants were administered a single oral dose (120 mg) of fexofenadine during constitutive P-gp and OATP1B1/3 conditions. Concentration-time data were divided into a training (n = 18) and validation (n = 35) set. Backwards stepwise linear regression generated single-, 2-timepoint, and partial AUC limited sampling models (LSMs). Noncompartmental analysis methods were used to determine total AUC (AUC_0–lNF) from intensive sampling. Coefficient of determination (r²) and bias and precision were assessed via relative percent mean prediction error (%MPE), relative percent mean absolute error (%MAE), and relative percent root mean square error (%RMSE).
Results: The geometric mean observed AUC_0–INF was 1,680 ng×h/mL. The 2-, 5-, and 2- plus 5-hour LSMs met backwards stepwise linear regression significance (p < 0.15) to remain in the model but had unacceptable %RMSE (17 – 29%). The majority of partial AUC LSMs had unacceptable r² (0.21 – 0.83), with all models having unacceptable %MAE (12 – 35%).
Conclusion: Fexofenadine limited sampling strategy using single-timepoint, 2-timepoint, and partial AUCs were unable to accurately estimate AUC_0–lNF and thus constitutive P-gp and OATB1B1/3 activities in healthy adults. Timepoints that were not measured or selected may have improved LSM performance.Correspondence to:
Joseph D. Ma, PharmD
University of California, San Diego
Skaggs School of Pharmacy and Pharmaceutical Sciences
9500 Gilman Drive, MC 0657
La Jolla, CA 92093-0657, USA
Email: [email protected]

Shopping Overview

Shopping Overview
Type	Qtty	Discount	VAT	Price
Your basket is empty

View Cart

Search Results

Shopping Overview

Send us an E-Mail