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Tachibana M, Matsuki S, Maekawa Y, Kuroda K, Shimizu T, Tsutsumi J, Ishizuka H. Effect of itraconazole and fluconazole on the pharmacokinetics of valemetostat: An open-label, phase I study in healthy subjects. Clin Transl Sci 2023; 16:2153-2162. [PMID: 37705321 PMCID: PMC10651645 DOI: 10.1111/cts.13613] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2023] [Revised: 07/27/2023] [Accepted: 08/03/2023] [Indexed: 09/15/2023] Open
Abstract
Valemetostat tosylate (valemetostat) is an oral, potent, dual inhibitor of enhancer of zeste homolog (EZH) 2 and EZH1 under investigation for the treatment of cancer, including non-Hodgkin's lymphomas and solid tumors. Itraconazole and fluconazole are antifungal medications often used as typical inhibitors of cytochrome P450 3A (CYP3A [itraconazole and fluconazole]) and P-glycoprotein (P-gp [itraconazole]) in drug-drug interaction studies. Valemetostat is a substrate of CYP3A and P-gp in vitro. This phase I, open-label, single-sequence crossover study (JapicCTI-183902) assessed the pharmacokinetics (PK) of valemetostat when co-administered with itraconazole (a strong CYP3A inhibitor and P-gp inhibitor) or fluconazole (a moderate CYP3A inhibitor) in healthy Japanese male participants 20-45 years of age. Participants were equally allocated to receive two doses of valemetostat 25 mg, once alone and once with either itraconazole or fluconazole (400-mg induction and 200-mg once daily maintenance). Valemetostat PK parameters with versus without itraconazole or fluconazole were compared using analysis of variance models. Overall, 32 participants were enrolled. Co-administration with itraconazole increased valemetostat peak concentration (Cmax ) by 2.9-fold and area under the plasma concentration-time curve extrapolated to infinity (AUCinf ) by 4.2-fold compared with valemetostat alone. When co-administered with fluconazole, the Cmax and AUCinf of valemetostat were each increased by 1.6-fold. No treatment-related or grade ≥3 adverse events were reported. Appropriate valemetostat dose reductions are warranted when used concomitantly with strong CYP3A and P-gp dual inhibitors.
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Pharmacokinetic Drug-Drug Interaction of Apalutamide, Part 1: Clinical Studies in Healthy Men and Patients with Castration-Resistant Prostate Cancer. Clin Pharmacokinet 2021; 59:1135-1148. [PMID: 32338345 DOI: 10.1007/s40262-020-00882-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
BACKGROUND AND OBJECTIVES Two phase I studies assessed the drug-drug interaction potential of apalutamide as a substrate and perpetrator. METHODS Study A randomized 45 healthy men to single-dose apalutamide 240 mg alone or with strong inhibitors of cytochrome P450 (CYP)3A4 (itraconazole) or CYP2C8 (gemfibrozil). In study B, 23 patients with castration-resistant prostate cancer received probes for CYP3A4 (midazolam), CYP2C9 (warfarin), CYP2C19 (omeprazole), and CYP2C8 (pioglitazone), and transporter substrates for P-glycoprotein (P-gp) (fexofenadine) and breast cancer resistance protein (BCRP)/organic anion transporting polypeptide (OATP) 1B1 (rosuvastatin) at baseline and after repeat once-daily administration of apalutamide 240 mg to steady state. RESULTS Systemic exposure (area under the plasma concentration-time curve) to single-dose apalutamide increased 68% with gemfibrozil but was relatively unchanged with itraconazole (study A). Apalutamide reduced systemic exposure to midazolam ↓92%, omeprazole ↓85%, S-warfarin ↓46%, fexofenadine ↓30%, rosuvastatin ↓41%, and pioglitazone ↓18% (study B). After a single dose, apalutamide is predominantly metabolized by CYP2C8, and less by CYP3A4. CONCLUSIONS Co-administration of apalutamide with CYP3A4, CYP2C19, CYP2C9, P-gp, BCRP or OATP1B1 substrates may cause loss of activity for these medications. Therefore, appropriate mitigation strategies are recommended.
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Hsueh CH, Anderson K, Shen G, Yun C, Qin A, Othman AA. Evaluation of the potential drug interactions mediated through P-gp, OCT2, and MATE1/2K with filgotinib in healthy subjects. Clin Transl Sci 2021; 15:361-370. [PMID: 34498807 PMCID: PMC8841438 DOI: 10.1111/cts.13152] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2021] [Revised: 07/15/2021] [Accepted: 08/12/2021] [Indexed: 01/24/2023] Open
Abstract
Filgotinib, a preferential Janus Kinase-1 inhibitor, is approved in Europe and Japan for treatment of rheumatoid arthritis and is being developed for treatment of other chronic inflammatory diseases. Three drug-drug interactions studies were conducted in healthy subjects to evaluate the effect of P-glycoprotein (P-gp) modulation (study 1: P-gp inhibition by itraconazole and study 2: P-gp induction by rifampin) on filgotinib pharmacokinetics and the potential of filgotinib to impact exposure of metformin, an organic cation transporter (OCT) 2 and multidrug and toxin extrusion (MATE) 1/2K substrate (study 3). Co-administration of filgotinib with itraconazole increased filgotinib exposure (maximum concentration [Cmax ] by 64% and area under the curve to infinity [AUCinf ] by 45%) but had no effect on the exposure of GS-829845, filgotinib's primary metabolite. Rifampin moderately reduced exposures of filgotinib and GS-829845 (Cmax by 26% and AUCinf by 27% for filgotinib; Cmax by 19% and AUCinf by 38% for GS-829845). The data confirmed that filgotinib is a P-gp substrate. However, the magnitude of change in filgotinib/GS-829845 exposure by P-gp modulators is not deemed to be clinically relevant based on filgotinib exposure-response analyses in subjects with rheumatoid arthritis. Filgotinib did not alter metformin exposures, indicating that filgotinib and GS-829845 do not inhibit OCT2 and MATE1/2K at the clinical doses. Filgotinib was generally well-tolerated when administered alone or with the co-administered drugs in the studies. Results from these studies were the basis to enable the use of P-gp modulators and substrates of OCT2, MATE1, and MATE2K with filgotinib without the need for dose modifications in the current approved rheumatoid arthritis population.
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Affiliation(s)
| | | | - Gong Shen
- Gilead Sciences, Inc., Foster City, California, USA
| | - Chohee Yun
- Gilead Sciences, Inc., Foster City, California, USA
| | - Ann Qin
- Gilead Sciences, Inc., Foster City, California, USA
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Sane RS, Cheung KWK, Cho E, Liederer BM, Hanover J, Malhi V, Plise E, Wong S, Musib L. Evaluation of Ipatasertib Interactions with Itraconazole and Coproporphyrin I and III in a Single Drug Interaction Study in Healthy Subjects. J Pharmacol Exp Ther 2021; 378:87-95. [PMID: 34049965 DOI: 10.1124/jpet.121.000620] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2021] [Accepted: 05/24/2021] [Indexed: 12/23/2022] Open
Abstract
Ipatasertib is a pan-AKT inhibitor in development for the treatment of cancer. Ipatasertib was metabolized by CYP3A4 to its major metabolite, M1 (G-037720), and was a P-gp substrate and OATP1B1/1B3 inhibitor in vitro. A phase I drug-drug interaction (DDI) study (n = 15) was conducted in healthy subjects to evaluate the effect of itraconazole (200-mg solution QD, 4 days), a strong CYP3A4 and P-gp inhibitor, on pharmacokinetics of ipatasertib (100-mg single dose). Itraconazole increased the Cmax and AUC0 -∞ of ipatasertib by 2.3- and 5.5-fold, respectively, increased the half-life by 53%, and delayed the tmax by 1 hour. The Cmax and AUC0-72h of its metabolite M1 (G-037720) reduced by 91% and 68%, respectively. This study confirmed that CYP3A4 plays a major role in ipatasertib clearance. Furthermore, the interaction of ipatasertib with coproporphyrin (CP) I and CPIII, the two endogenous substrates of OATP1B1/1B3, was evaluated in this study. CPI and CPIII plasma levels were unchanged in the presence of ipatasertib, both at exposures of 100 mg and at higher exposures in combination with itraconazole. This indicated no in vivo inhibition of OATP1B1/1B3 by ipatasertib. Additionally, it was shown that CPI and CPIII were not P-gp substrates in vitro, and itraconazole had no effect on CPI and CPIII concentrations in vivo. The latter is an important finding because it will simplify interpretation of future DDI studies using CPI/CPIII as OATP1B1/1B3 biomarkers. SIGNIFICANCE STATEMENT: This drug-drug interaction study in healthy volunteers demonstrated that CYP3A4 plays a major role in ipatasertib clearance, and that ipatasertib is not an organic anion transporting polypeptide 1B1/1B3 inhibitor. Furthermore, it was demonstrated that itraconazole, an inhibitor of CYP3A4 and several transporters, did not affect CPI/CPIII levels in vivo. This increases the understanding and application of these endogenous substrates as well as itraconazole in complex drug interaction studies.
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Affiliation(s)
| | | | - Eunpi Cho
- Genentech, South San Francisco, California
| | | | | | | | | | - Susan Wong
- Genentech, South San Francisco, California
| | - Luna Musib
- Genentech, South San Francisco, California
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Peniche AG, Osorio EY, Melby PC, Travi BL. Efficacy of histamine H1 receptor antagonists azelastine and fexofenadine against cutaneous Leishmania major infection. PLoS Negl Trop Dis 2020; 14:e0008482. [PMID: 32776923 PMCID: PMC7449455 DOI: 10.1371/journal.pntd.0008482] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Revised: 08/26/2020] [Accepted: 06/13/2020] [Indexed: 11/18/2022] Open
Abstract
Current drug therapies for cutaneous leishmaniasis are often difficult to administer and treatment failure is an increasingly common occurrence. The efficacy of anti-leishmanial therapy relies on a combination of anti-parasite activity of drugs and the patient’s immune response. Previous studies have reported in vitro antimicrobial activity of histamine 1-receptor antagonists (H1RAs) against different pathogens. We used an ex vivo explant culture of lymph nodes from mice infected with Leishmania major to screen H1RAs compounds. Azelastine (AZ) and Fexofenadine (FX) showed remarkable ex vivo efficacy (EC50 = 0.05 and 1.50 μM respectively) and low in vitro cytotoxicity yielding a high therapeutic index. AZ significantly decreased the expression of H1R and the proinflammatory cytokine IL-1ẞ in the ex vivo system, which were shown to be augmented by histamine addition. The anti-leishmanial efficacy of AZ was enhanced in the presence of T cells from infected mice suggesting an immune-modulatory mechanism of parasite suppression. L. major infected BALB/c mice treated per os with FX or intralesionally with AZ showed a significant reduction of lesion size (FX = 69%; AZ = 52%). Furthermore, there was significant parasite suppression in the lesion (FX = 82%; AZ = 87%) and lymph nodes (FX = 81%; AZ = 36%) with no observable side effects. AZ and FX and potentially other H1RAs are good candidates for assessing efficacy in larger studies as monotherapies or in combination with current anti-leishmanial drugs to treat cutaneous leishmaniasis. Cutaneous leishmaniasis (CL) is a parasitic disease present in more than 90 countries. Different species of Leishmania produce skin ulcers upon infection through the bite of infected sand fly vectors. There are several drugs used to treat CL but most of them are toxic or difficult to administer and there is increasing drug resistance leading to treatment failure. Therefore, new drugs are needed for treating CL. The objective of this study was to determine the anti-leishmanial efficacy of antihistamine drugs. Using cell cultures of lymph nodes obtained from Leishmania major infected mice, we evaluated the parasiticidal activity of the antihistamine drugs azelastine and fexofenadine. Both drugs showed high efficacy against L. major and low toxicity for a human cell line. Treatment of mice infected in the skin with L. major indicated that both azelastine and fexofenadine significantly reduced the size of the lesions and suppressed parasite multiplication. Consequently, these two drugs are good candidates to further evaluate their efficacy as monotherapies or in combination with other anti-leishmanial drugs.
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Affiliation(s)
- Alex G. Peniche
- Department of Internal Medicine, University of Texas Medical Branch, Galveston, Texas, United States of America
| | - E. Yaneth Osorio
- Department of Internal Medicine, University of Texas Medical Branch, Galveston, Texas, United States of America
| | - Peter C. Melby
- Department of Internal Medicine, University of Texas Medical Branch, Galveston, Texas, United States of America
- Center for Tropical Diseases, University of Texas Medical Branch, Galveston, Texas, United States of America
| | - Bruno L. Travi
- Department of Internal Medicine, University of Texas Medical Branch, Galveston, Texas, United States of America
- Center for Tropical Diseases, University of Texas Medical Branch, Galveston, Texas, United States of America
- * E-mail:
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Kobayashi K, Abe Y, Kawai A, Furihata T, Endo T, Takeda H. Pharmacokinetic Drug Interactions of an Orally Available TRH Analog (Rovatirelin) With a CYP3A4/5 and P-Glycoprotein Inhibitor (Itraconazole). J Clin Pharmacol 2020; 60:1314-1323. [PMID: 32459872 DOI: 10.1002/jcph.1628] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2020] [Accepted: 03/27/2020] [Indexed: 01/11/2023]
Abstract
The effects of itraconazole on the pharmacokinetics of rovatirelin were investigated in an open-label, single-sequence drug-drug interaction study in 16 healthy subjects. Subjects were administered a single oral dose of rovatirelin (1.6 mg) on day 1 and day 15. From day 8 through 16, subjects received daily oral doses of itraconazole (200 mg/day). Concentrations of rovatirelin and (thiazolylalanyl)methylpyrrolidine (TAMP), the major metabolite of rovatirelin formed by cytochrome P450 (CYP) 3A4/5, were determined in plasma and urine. Pharmacokinetic parameters were used to evaluate the drug-drug interaction potential of rovatirelin as a victim. With coadministration, maximum concentration (Cmax ) and area under the concentration-time curve extrapolated to infinity (AUCinf ) of rovatirelin increased 3.05-fold and 2.82-fold, respectively, and the 90% confidence intervals of the ratios for Cmax (2.64-3.52) and AUCinf (2.47-3.23) did not fall within the 0.8-1.25 boundaries. Urinary excretion of rovatirelin increased at almost the same ratio as the AUCinf ratio with coadministration; however, renal clearance did not change. Cmax , AUCinf , and urinary excretion of TAMP were decreased by coadministration. Itraconazole has the potential to inhibit drug transport via intestinal P-glycoprotein (P-gp) and breast cancer resistance protein (BCRP); therefore, substrate assessments of rovatirelin for the 2 transporters were evaluated using Caco-2 cell monolayers. In vitro studies showed that rovatirelin is a substrate for P-gp but not for BCRP. The current study shows that itraconazole's effect on rovatirelin pharmacokinetics is mediated through inhibition of CYP3A4/5 and intestinal P-gp.
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Affiliation(s)
- Kaoru Kobayashi
- Central Research Laboratories, Kissei Pharmaceutical Co, Ltd., Azumino, Nagano, Japan
| | - Yoshikazu Abe
- Central Research Laboratories, Kissei Pharmaceutical Co, Ltd., Azumino, Nagano, Japan
| | - Asuka Kawai
- Clinical Development Division, Kissei Pharmaceutical Co, Ltd., Bunkyo, Tokyo, Japan
| | - Takao Furihata
- Clinical Development Division, Kissei Pharmaceutical Co, Ltd., Bunkyo, Tokyo, Japan
| | - Takuro Endo
- Central Research Laboratories, Kissei Pharmaceutical Co, Ltd., Azumino, Nagano, Japan
| | - Hiroo Takeda
- Central Research Laboratories, Kissei Pharmaceutical Co, Ltd., Azumino, Nagano, Japan
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Akamine Y, Yasui-Furukori N, Uno T. Drug-Drug Interactions of P-gp Substrates Unrelated to CYP Metabolism. Curr Drug Metab 2019; 20:124-129. [PMID: 30280663 DOI: 10.2174/1389200219666181003142036] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2018] [Revised: 08/31/2018] [Accepted: 09/04/2018] [Indexed: 01/16/2023]
Abstract
BACKGROUND Recent US Food and Drug Administration (FDA) draft guidance on pharmacokinetic drugdrug interactions (DDIs) has highlighted the clinical importance of ABC transporters B1 or P-glycoprotein (P-gp), hepatic organic anion-transporting polypeptide transporters and breast cancer resistant protein because of their broad substrate specificity and the potential to be involved in DDIs. This guidance has indicated that digoxin, dabigatran etexilate and fexofenadine are P-gp substrate drugs and has defined P-gp inhibitors as those that increase the AUC of digoxin by ≧1.25-fold in clinical DDI studies. However, when substrate drugs of both CYPs and P-gp are involved in DDIs, it remains that the mechanisms of DDIs will be quite ambiguous in assessing how much the CYPs and/or drug transporters partially contribute to DDIs. OBJECTIVE Since there are no detailed manuscripts that summarizes P-gp interactions unrelated to CYP metabolism, this article reviews the effects of potent P-gp inhibitors and P-gp inducers on the pharmacokinetics of P-gp substrate drugs, including digoxin, talinolol, dabigatran etexilate, and fexofenadine in human studies. In addition, the present outcome were to determine the PK changes caused by DDIs among P-gp substrate drugs without CYP metabolism in human DDI studies. CONCLUSION Our manuscript concludes that the PK changes of the DDIs among P-gp drugs unrelated to CYP metabolism are less likely to be serious, and it appears to be convincing that the absences of clinical effects caused to the PK changes by the P-gp inducers is predominant compared with the excessive effects caused to those by the P-gp inhibitors.
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Affiliation(s)
- Yumiko Akamine
- Department of Pharmacy, Akita University Hospital, Akita, Japan
| | - Norio Yasui-Furukori
- Department of Neuropsychiatry, Hirosaki University School of Medicine, Hirosaki, Japan
| | - Tsukasa Uno
- Department of Hospital Pharmacy, Zikeikai-Aoimori Hospital, Aomori, Japan
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Tod M, Goutelle S, Bleyzac N, Bourguignon L. A Generic Model for Quantitative Prediction of Interactions Mediated by Efflux Transporters and Cytochromes: Application to P-Glycoprotein and Cytochrome 3A4. Clin Pharmacokinet 2018; 58:503-523. [DOI: 10.1007/s40262-018-0711-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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Akamine Y, Miura M. An update on the clinical pharmacokinetics of fexofenadine enantiomers. Expert Opin Drug Metab Toxicol 2018; 14:429-434. [DOI: 10.1080/17425255.2018.1459565] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Yumiko Akamine
- Department of Pharmacy, Akita University Hospital, Akita, Japan
| | - Masatomo Miura
- Department of Pharmacy, Akita University Hospital, Akita, Japan
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Evaluation of P-Glycoprotein Inhibitory Potential Using a Rhodamine 123 Accumulation Assay. Pharmaceutics 2016; 8:pharmaceutics8020012. [PMID: 27077878 PMCID: PMC4932475 DOI: 10.3390/pharmaceutics8020012] [Citation(s) in RCA: 96] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2016] [Revised: 03/22/2016] [Accepted: 04/06/2016] [Indexed: 11/17/2022] Open
Abstract
In vitro evaluation of P-glycoprotein (P-gp) inhibitory potential is now a regulatory issue during drug development, in order to predict clinical inhibition of P-gp and subsequent drug-drug interactions. Assays for this purpose, commonly based on P-gp-expressing cell lines and digoxin as a reference P-gp substrate probe, unfortunately exhibit high variability, raising thus the question of developing alternative or complementary tests for measuring inhibition of P-gp activity. In this context, the present study was designed to investigate the use of the fluorescent dye rhodamine 123 as a reference P-gp substrate probe for characterizing P-gp inhibitory potential of 16 structurally-unrelated drugs known to interact with P-gp. 14/16 of these P-gp inhibitors were found to increase rhodamine 123 accumulation in P-gp-overexpressing MCF7R cells, thus allowing the determination of their P-gp inhibitory potential, i.e., their half maximal inhibitor concentration (IC50) value towards P-gp-mediated transport of the dye. These IC50 values were in the range of variability of previously reported IC50 for P-gp and can be used for the prediction of clinical P-gp inhibition according to Food and Drug Administration (FDA) criteria, with notable sensitivity (80%). Therefore, the data demonstrated the feasibility of the use of rhodamine 123 for evaluating the P-gp inhibitory potential of drugs.
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Srinivas NR. Prediction of area under the curve for a p-glycoprotein, a CYP3A4 and a CYP2C9 substrate using a single time point strategy: assessment using fexofenadine, itraconazole and losartan and metabolites. Drug Dev Ind Pharm 2015; 42:945-57. [DOI: 10.3109/03639045.2015.1096278] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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An G, Mukker JK, Derendorf H, Frye RF. Enzyme- and transporter-mediated beverage-drug interactions: An update on fruit juices and green tea. J Clin Pharmacol 2015; 55:1313-31. [DOI: 10.1002/jcph.563] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2014] [Accepted: 06/03/2015] [Indexed: 01/06/2023]
Affiliation(s)
- Guohua An
- Department of Pharmaceutical Sciences and Experimental Therapeutics; College of Pharmacy; University of Iowa; Iowa City IA USA
| | - Jatinder Kaur Mukker
- Department of Pharmaceutics; College of Pharmacy; University of Florida; Gainesville FL USA
| | - Hartmut Derendorf
- Department of Pharmaceutics; College of Pharmacy; University of Florida; Gainesville FL USA
| | - Reginald F. Frye
- Department of Pharmacotherapy and Translational Research; College of Pharmacy; University of Florida; Gainesville FL USA
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Effects of danshen ethanol extract on the pharmacokinetics of fexofenadine in healthy volunteers. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2014; 2014:473213. [PMID: 25538791 PMCID: PMC4235188 DOI: 10.1155/2014/473213] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/12/2014] [Accepted: 08/30/2014] [Indexed: 11/18/2022]
Abstract
This study investigated the effect of multidose administration of danshen ethanol extract on fexofenadine pharmacokinetics in healthy volunteers. A sequential, open-label, two-period pharmacokinetic interaction design was used. 12 healthy male volunteers received a single oral dose of fexofenadine (60 mg) followed by danshen ethanol extract (1 g orally, three times a day) for 10 days, after which they received 1 g of the danshen extract with fexofenadine (60 mg) on the last day. The plasma concentrations of fexofenadine was measured by LC-MS/MS. After 10 days of the danshen extract administration, the mean AUC and Cmax of the fexofenadine was decreased by 37.2% and 27.4% compared with the control, respectively. The mean clearance of fexofenadine was increased by 104.9%. The in vitro study showed that tanshinone IIA and cryptotanshinone could induce MDR1 mRNA. This study showed that multidose administration of danshen ethanol extract could increase oral clearance of fexofenadine. The increased oral clearance of fexofenadine is attributable to induction of intestinal P-glycoprotein.
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Zhao Y, Hu ZY. Physiologically based pharmacokinetic modelling and in vivo [I]/K(i) accurately predict P-glycoprotein-mediated drug-drug interactions with dabigatran etexilate. Br J Pharmacol 2014; 171:1043-53. [PMID: 24283665 DOI: 10.1111/bph.12533] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2013] [Revised: 11/18/2013] [Accepted: 11/25/2013] [Indexed: 01/26/2023] Open
Abstract
BACKGROUND AND PURPOSE In vitro inhibitory potency (Ki )-based predictions of P-glycoprotein (P-gp)-mediated drug-drug interactions (DDIs) are hampered by the substantial variability in inhibitory potency. In this study, in vivo-based [I]/Ki values were used to predict the DDI risks of a P-gp substrate dabigatran etexilate (DABE) using physiologically based pharmacokinetic (PBPK) modelling. EXPERIMENTAL APPROACH A baseline PBPK model was established with digoxin, a known P-gp substrate. The Km (P-gp transport) of digoxin in the baseline PBPK model was adjusted to Km (i) to fit the change of digoxin pharmacokinetics in the presence of a P-gp inhibitor. Then 'in vivo' [I]/Ki of this P-gp inhibitor was calculated using Km (i) /Km . Baseline PBPK model was developed for DABE, and the 'in vivo' [I]/Ki was incorporated into this model to simulate the static effect of P-gp inhibitor on DABE pharmacokinetics. This approach was verified by comparing the observed and the simulated DABE pharmacokinetics in the presence of five different P-gp inhibitors. KEY RESULTS This approach accurately predicted the effects of five P-gp inhibitors on DABE pharmacokinetics (98-133% and 89-104% for the ratios of AUC and Cmax respectively). The effects of 16 other P-gp inhibitors on the pharmacokinetics of DABE were also confidently simulated. CONCLUSIONS AND IMPLICATIONS 'In vivo' [I]/Ki and PBPK modelling, used in combination, can accurately predict P-gp-mediated DDIs. The described framework provides a mechanistic basis for the proper design of clinical DDI studies, as well as avoiding unnecessary clinical DDI studies.
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Affiliation(s)
- Yuansheng Zhao
- The Hamner Institutes for Health Sciences, Research Triangle Park, NC, USA
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Umeyama Y, Fujioka Y, Okuda T. Clarification of P-glycoprotein inhibition-related drug–drug interaction risks based on a literature search of the clinical information. Xenobiotica 2014; 44:1135-44. [DOI: 10.3109/00498254.2014.928958] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Kusuhara H, Miura M, Yasui-Furukori N, Yoshida K, Akamine Y, Yokochi M, Fukizawa S, Ikejiri K, Kanamitsu K, Uno T, Sugiyama Y. Effect of Coadministration of Single and Multiple Doses of Rifampicin on the Pharmacokinetics of Fexofenadine Enantiomers in Healthy Subjects. Drug Metab Dispos 2012; 41:206-13. [DOI: 10.1124/dmd.112.048330] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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Different effects of the selective serotonin reuptake inhibitors fluvoxamine, paroxetine, and sertraline on the pharmacokinetics of fexofenadine in healthy volunteers. J Clin Psychopharmacol 2012; 32:195-9. [PMID: 22367658 DOI: 10.1097/jcp.0b013e318248ddb9] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Although the interaction between selective serotonin reuptake inhibitors (SSRIs) and other drugs is important in the treatment of depression, there have been few studies of SSRIs concerning transporter-mediated interactions in humans. The objective of this study was to evaluate the in vivo effects of commonly used SSRIs on the pharmacokinetics of fexofenadine, a P-glycoprotein substrate.Twelve healthy volunteers (3 females and 9 males) were enrolled in this study. Each subject received a 60-mg dose of fexofenadine orally at baseline. Afterward, they were randomly assigned to receive 3 treatments with a 60-mg dose of fexofenadine after a 7-day treatment with fluvoxamine (50 mg/d), paroxetine (20 mg/d), or sertraline (50 mg/d), with 2-week intervals between the agents.Fluvoxamine pretreatment significantly increased the maximum plasma concentration, the area under the concentration time curves, and the 24-hour urinary fexofenadine excretion by 66% (P = 0.004), 78% (P = 0.029), and 78% (P < 0.001), respectively, without prolonging its elimination half-life. Paroxetine extended the elimination half-life of fexofenadine by 45% (P = 0.042), and it increased the 24-hour urinary fexofenadine excretion by 55% (P = 0.002). Sertraline did not alter any of the pharmacokinetic parameters of fexofenadine.This is the first report of the different effects of 3 commonly used SSRIs on fexofenadine pharmacokinetics in humans. Our 7-day, repeated-dose clinical study in healthy volunteers indicates that fluvoxamine and paroxetine, but not sertraline, may impact the patient exposure to fexofenadine, which is likely the result of P-glycoprotein inhibition in the small intestine and/or the liver.
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Bailey DG. Fruit juice inhibition of uptake transport: a new type of food-drug interaction. Br J Clin Pharmacol 2011; 70:645-55. [PMID: 21039758 DOI: 10.1111/j.1365-2125.2010.03722.x] [Citation(s) in RCA: 149] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
A new type of interaction in which fruit juices diminish oral drug bioavailability through inhibition of uptake transport is the focus of this review. The discovery was based on an opposite to anticipated finding when assessing the possibility of grapefruit juice increasing oral fexofenadine bioavailability in humans through inhibition of intestinal MDR1-mediated efflux transport. In follow-up investigations, grapefruit or orange juice at low concentrations potentially and selectively inhibited in vitro OATP1A2-mediated uptake compared with MDR1-caused efflux substrate transport. These juices at high volume dramatically depressed oral fexofenadine bioavailability. Grapefruit was the representative juice to characterize the interaction subsequently. A volume-effect relationship study using a normal juice amount halved average fexofenadine absorption. Individual variability and reproducibility data indicated the clinical interaction involved direct inhibition of intestinal OATP1A2. Naringin was a major causal component suggesting that other flavonoids in fruits and vegetables might also produce the effect. Duration of juice clinical inhibition of fexofenadine absorption lasted more than 2 h but less than 4 h indicating the interaction was avoidable with appropriate interval of time between juice and drug consumption. Grapefruit juice lowered the oral bioavailability of several medications transported by OATP1A2 (acebutolol, celiprolol, fexofenadine, talinolol, L-thyroxine) while orange juice did the same for others (atenolol, celiprolol, ciprofloxacin, fexofenadine). Juice clinical inhibition of OATP2B1 was unresolved while that of OATP1B1 seemed unlikely. The interaction between grapefruit juice and etoposide also seemed relevant. Knowledge of both affected uptake transporter and drug hydrophilicity assisted prediction of the clinical interaction with grapefruit or orange juice.
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Affiliation(s)
- David G Bailey
- Department of Medicine and Lawson Health Research Institute, London Health Sciences Centre Department of Physiology & Pharmacology, University of Western Ontario, London, Ontario, Canada.
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Shord SS, Chan LN, Camp JR, Vasquez EM, Jeong HY, Molokie RE, Baum CL, Xie H. Effects of oral clotrimazole troches on the pharmacokinetics of oral and intravenous midazolam. Br J Clin Pharmacol 2010; 69:160-6. [PMID: 20233179 DOI: 10.1111/j.1365-2125.2009.03559.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
AIMS The aim of the study was to determine the effects of oral clotrimazole troches on the pharmacokinetics of oral and intravenous midazolam in the plasma. METHODS We conducted a randomized, open-label, four-way crossover study in 10 healthy volunteers. Each volunteer received oral midazolam 2 mg or intravenous midazolam 0.025 mg kg(-1) with and without oral clotrimazole troches 10 mg taken three times daily for 5 days. Each study period was separated by 14 days. Serial blood samples were collected up to 24 h after oral midazolam and 6 h after intravenous midazolam. Plasma concentrations for midazolam and its metabolite 1-hydroxymidazolam were measured and fitted to a noncompartmental model to estimate the pharmacokinetic parameters. RESULTS Ten healthy volunteers aged 21-26 years provided written informed consent and were enrolled into the study. Clotrimazole decreased the apparent oral clearance of midazolam from 57 +/- 13 l h(-1)[95% confidence interval 48, 66] to 36 +/- 9.8 l h(-1) (95% confidence interval 29, 43) (P= 0.003). These changes were accompanied by a decrease in the area under the concentration-time curve (mean difference 22 microg h(-1) l(-1), P= 0.001) and bioavailability (mean difference 0.21, P= NS). There were no significant differences in the systemic clearance of midazolam with or without clotrimazole troches. CONCLUSIONS Oral clotrimazole troches decreased the apparent oral clearance of midazolam; no significant differences in the systemic clearance of midazolam were found.
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Affiliation(s)
- Stacy S Shord
- Department of Pharmacy Practice, College of Pharmacy, University of Illinois, Chicago, IL, USA.
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Ma JD, Tsunoda SM, Bertino JS, Trivedi M, Beale KK, Nafziger AN. Evaluation of in vivo P-glycoprotein phenotyping probes: a need for validation. Clin Pharmacokinet 2010; 49:223-37. [PMID: 20214407 DOI: 10.2165/11318000-000000000-00000] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Drug transporters are involved in clinically relevant drug-drug interactions. P-glycoprotein (P-gp) is an efflux transporter that displays genetic polymorphism. Phenotyping permits evaluation of real-time, in vivo P-gp activity and P-gp-mediated drug-drug interactions. Digoxin, fexofenadine, talinolol and quinidine are commonly used probe drugs for P-gp phenotyping. Although current regulatory guidance documents highlight methodologies for evaluating transporter-based drug-drug interactions, whether current probe drugs are suitable for phenotyping has not been established, and validation criteria are lacking. This review proposes validation criteria and evaluates P-gp probes to determine probe suitability. Based on these criteria, digoxin, fexofenadine, talinolol and quinidine have limitations to their use and are not recommended for P-gp phenotyping.
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Affiliation(s)
- Joseph D Ma
- University of California, San Diego, La Jolla, 92093, USA.
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Effects of the P-glycoprotein Inducer Carbamazepine on Fexofenadine Pharmacokinetics. Ther Drug Monit 2009; 31:764-8. [DOI: 10.1097/ftd.0b013e3181bf7db6] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Miura M, Uno T. Clinical pharmacokinetics of fexofenadine enantiomers. Expert Opin Drug Metab Toxicol 2009; 6:69-74. [DOI: 10.1517/17425250903382615] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Update on prescription and over-the-counter histamine inverse agonists in rhinitis therapy. Curr Allergy Asthma Rep 2009; 9:140-8. [PMID: 19210904 DOI: 10.1007/s11882-009-0021-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Allergic rhinitis (AR) is associated with histamine-mediated physiologic events. The currently used histamine antagonists are all inverse agonists that bind and inactivate histamine H1 receptors. Second-generation antihistamines are much more H1-receptor selective with less central nervous system penetration than first-generation agents. Antihistamines typically are more effective in seasonal than perennial AR and do not demonstrate significant relief of nasal congestion. The recent availability of some second-generation antihistamines as over-the-counter products clearly places them as the preferred first-line treatment for mild to moderate AR based on safety when compared with first-generation over-the-counter antihistamines. The remaining prescription-only second-generation antihistamines, fexofenadine, desloratadine, and levocetirizine, all have unique attributes. Antihistamines in oral, intranasal, or intraocular formulations will likely remain among the mainstays of allergy therapeutics.
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Heiskanen T, Backman JT, Neuvonen M, Kontinen VK, Neuvonen PJ, Kalso E. Itraconazole, a potent inhibitor of P-glycoprotein, moderately increases plasma concentrations of oral morphine. Acta Anaesthesiol Scand 2008; 52:1319-26. [PMID: 19025521 DOI: 10.1111/j.1399-6576.2008.01739.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
BACKGROUND Individual variation in opioid response is considerable, partly due to pharmacokinetic factors. Transporter proteins are becoming increasingly interesting also in the pharmacokinetics of opioids. The efflux transporter P-glycoprotein can affect gastrointestinal absorption and tissue distribution, particularly brain access of many opioids. The aim of this study was to evaluate whether itraconazole, which is a potent inhibitor of P-glycoprotein and CYP3A4, would change the pharmacokinetics or the pharmacodynamics of oral morphine. METHODS Twelve healthy male volunteers ingested, in a randomized crossover study, once daily 200 mg itraconazole or placebo for 4 days. On day 4, 1 h after the last pre-treatment dose, the subjects ingested 0.3 mg/kg morphine. Blood samples for the determination of plasma morphine, morphine-3-glucuronide (M3G), morphine-6-glucuronide (M6G) and itraconazole concentrations were drawn up to 48 h after morphine ingestion. Pharmacodynamic effects were evaluated using a questionnaire, visual analogue scales, a reaction time test, the Digit Symbol Substitution Test and the Critical Flicker Fusion Test. RESULTS Itraconazole increased the mean area under the plasma concentration-time curve [AUC (0-9)] of morphine by 29% (P=0.002), its AUC (0-48) by 22% (P=0.013) and its peak plasma concentration by 28% (P=0.035). Itraconazole did not significantly affect the pharmacokinetic variables of M3G or M6G or the pharmacodynamic effects of morphine. CONCLUSIONS Itraconazole moderately increases plasma concentrations of oral morphine, probably by enhancing its absorption by inhibiting intestinal wall P-glycoprotein. A possible improvement of morphine penetration to the brain could not be observed.
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Affiliation(s)
- T Heiskanen
- Pain Clinic, Department of Anaesthesiology and Intensive Care Medicine, Helsinki University Central Hospital, Helsinki, Finland.
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Tateishi T, Miura M, Suzuki T, Uno T. The different effects of itraconazole on the pharmacokinetics of fexofenadine enantiomers. Br J Clin Pharmacol 2008; 65:693-700. [PMID: 18294330 DOI: 10.1111/j.1365-2125.2008.03116.x] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT Recently, we have shown that the plasma concentration of R-fexofenadine is greater than that of the S-enantiomer. Although itraconazole co-administration is known to increase the bioavailability of a racemic mixture of fexofenadine, little is known about the stereoselective inhibition of P-gp activity by itraconazole. WHAT THIS STUDY ADDS This study indicates that the stereoselective pharmacokinetics of fexofenadine are due to P-gp-mediated transport and its stereoselectivity is altered by itraconazole, a an inhibitor of P-gp. AIMS The aim of this study was to determine the inhibitory effect of itraconazole, a P-glycoprotein (P-gp) inhibitor, on the stereoselective pharmacokinetics of fexofenadine. METHODS A two-way double-blind, placebo-controlled crossover study was performed with a 2-week washout period. Twelve healthy volunteers received either itraconazole 200 mg or matched placebo in a randomized fashion with a single oral dose of fexofenadine 60 mg simultaneously. The plasma concentrations and the amount of urinary excretion (Ae) of fexofenadine enantiomers were measured up to 24 h after dosing. RESULTS After placebo administration, mean AUC(0,24 h) of S- and R-fexofenadine was 474 ng ml(-1) h (95% CI 311, 638) and 798 ng ml(-1) h (95% CI 497, 1101), respectively. Itraconazole affected the pharmacokinetic parameters of S-fexofenadine more, and increased AUC(0,24 h) of S-fexofenadine and R-fexofenadine by 4.0-fold (95% CI of differences 2.8, 5.3; P < 0.001) and by 3.1-fold (95% CI of differences 2.2, 4.0; P = 0.014), respectively, and Ae(0,24 h) of S-fexofenadine and R-fexofenadine by 3.6-fold (95% CI of differences 2.6, 4.5; P < 0.001) and by 2.9-fold (95% CI of differences 2.1, 3.8; P < 0.001), respectively. Additionally, the R : S ratio for AUC(0,24 h) and Ae(0,24 h) were significantly reduced in the itraconazole phase, while t(max), t(1/2) and renal clearance were constant during the study. CONCLUSIONS This study indicates that the stereoselective pharmacokinetics of fexofenadine are due to P-gp-mediated transport and its stereoselectivity is altered by itraconazole, a P-gp inhibitor. However, further study will be needed because the different affinities of the two enantiomers for P-gp have not been supported by in vitro studies.
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Affiliation(s)
- Tomonori Tateishi
- Department of Clinical Pharmacology, Hirosaki University School of Medicine, Hirosaki, Japan
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Matsushima S, Maeda K, Ishiguro N, Igarashi T, Sugiyama Y. Investigation of the inhibitory effects of various drugs on the hepatic uptake of fexofenadine in humans. Drug Metab Dispos 2008; 36:663-9. [PMID: 18180276 DOI: 10.1124/dmd.107.017814] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Fexofenadine (FEX), an H(1)-receptor antagonist, is eliminated from the liver mainly in an unchanged form. Our previous study suggested that organic anion-transporting polypeptide (OATP) 1B3 contributes mainly to the hepatic uptake of FEX. On the other hand, a clinical report demonstrated that a T521C mutation of OATP1B1 increased its plasma area under the plasma concentration-time curve. Several compounds are reported to have a drug interaction with FEX, and some of this may be caused by the inhibition of its hepatic uptake. We determined which transporters are involved in the hepatobiliary transport of FEX by using double transfectants and examined whether clinically reported drug interactions with FEX could be explained by the inhibition of its hepatic uptake. Vectorial basal-to-apical transport of FEX was observed in double transfectants expressing OATP1B1/multidrug resistance-associated protein 2 (MRP2) and OATP1B3/MRP2, suggesting that OATP1B1 as well as OATP1B3 is involved in the hepatic uptake of FEX and that MRP2 can recognize FEX as a substrate. The inhibitory effects of compounds on FEX uptake in OATP1B3-expressing HEK293 cells were investigated, and the maximal degree of increase in plasma AUC of FEX by drug interaction in clinical situations was estimated. As a result, cyclosporin A and rifampicin were found to have the potential to interact with OATP1B3-mediated uptake at clinical concentrations. From these results, most of the reported drug interaction cannot be explained by the inhibition of hepatic uptake of FEX, and different mechanisms such as the inhibition of intestinal efflux should be considered.
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Affiliation(s)
- Soichiro Matsushima
- Graduate School of Pharmaceutical Sciences, the University of Tokyo, Hongo, Bunkyo-ku, Tokyo, Japan
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Uno T, Shimizu M, Sugawara K, Tateishi T. Lack of dose-dependent effects of itraconazole on the pharmacokinetic interaction with fexofenadine. Drug Metab Dispos 2006; 34:1875-9. [PMID: 16928786 DOI: 10.1124/dmd.106.011023] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The aim of this study was to determine the inhibitory effect of itraconazole at different coadministered doses on fexofenadine pharmacokinetics. In a randomized four-phase crossover study, 11 healthy volunteers were administered a 60-mg fexofenadine hydrochloride tablet alone on one occasion (control phase) and with three different doses of 50, 100, and 200 mg of itraconazole simultaneously on the other three occasions (itraconazole phase). Although the elimination half-life and the renal clearance of fexofenadine remained relatively constant, a single administration of itraconazole with fexofenadine significantly increased mean area under the plasma concentration-time curve (AUC(0-infinity)) of fexofenadine (1701/3554, 4308, and 4107 ng h/ml for control; 50 mg, 100 mg, and 200 mg of itraconazole, respectively). Although mean itraconazole AUC(0-48) from 50 mg to 200 mg increased dose dependently from 214 to 772 ng h/ml (p = 0.003), no significant difference was noted in the three parameters, AUC (p = 0.423), C(max) (p = 0.636), and renal clearance (p = 0.495), of fexofenadine among the three doses of itraconazole. Itraconazole exposure at a lower dose (50 mg) compared with the clinical dose (200 mg once or twice daily) had the maximal effect on fexofenadine pharmacokinetics, even though itraconazole plasma concentrations gradually increased after higher doses. These findings suggest that the interaction may occur at the gut wall before reaching the portal vein circulation, and the inhibitory effect must be saturated by substantial local concentrations of itraconazole in the gut lumen after 50-mg dosing.
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Affiliation(s)
- Tsukasa Uno
- Department of Clinical Pharmacology, Hirosaki University School of Medicine, Hirosaki, Japan.
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