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Cardoso JLC, Lanchote VL, Pereira MPM, Capela JMV, de Moraes NV, Lepera JS. Impact of inhalational exposure to ethanol fuel on the pharmacokinetics of verapamil, ibuprofen and fluoxetine as in vivo probe drugs for CYP3A, CYP2C and CYP2D in rats. Food Chem Toxicol 2015; 84:99-105. [PMID: 26265240 DOI: 10.1016/j.fct.2015.08.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2015] [Revised: 06/23/2015] [Accepted: 08/01/2015] [Indexed: 11/28/2022]
Abstract
Occupational toxicology and clinical pharmacology integration will be useful to understand potential exposure-drug interaction and to shape risk assessment strategies in order to improve occupational health. The aim of the present study was to evaluate the effect of exposure to ethanol fuel on in vivo activities of cytochrome P450 (CYP) isoenzymes CYP3A, CYP2C and CYP2D by the oral administration of the probe drugs verapamil, ibuprofen and fluoxetine. Male Wistar rats exposed to filtered air or to 2000 ppm ethanol in a nose-only inhalation chamber during (6 h/day, 5 days/week, 6 weeks) received single oral doses of 10 mg/kg verapamil or 25 mg/kg ibuprofen or 10 mg/kg fluoxetine. The enantiomers of verapamil, norverapamil, ibuprofen and fluoxetine in plasma were analyzed by LC-MS/MS. The area under the curve plasma concentration versus time extrapolated to infinity (AUC(0-∞)) was calculated using the Gauss-Laguerre quadrature. Inhalation exposure to ethanol reduces the AUC of both verapamil (approximately 2.7 fold) and norverapamil enantiomers (>2.5 fold), reduces the AUC(0-∞) of (+)-(S)-IBU (approximately 2 fold) and inhibits preferentially the metabolism of (-)-(R)-FLU. In conclusion, inhalation exposure of ethanol at a concentration of 2 TLV-STEL (6 h/day for 6 weeks) induces CYP3A and CYP2C but inhibits CYP2D in rats.
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Affiliation(s)
- Juciane Lauren Cavalcanti Cardoso
- Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Brazil
| | - Vera Lucia Lanchote
- Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Brazil
| | - Maria Paula Marques Pereira
- Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Brazil
| | | | - Natália Valadares de Moraes
- Departamento de Princípios Ativos Naturais e Toxicologia, Faculdade de Ciências Farmacêuticas, Universidade Estadual Paulista, Brazil
| | - José Salvador Lepera
- Departamento de Princípios Ativos Naturais e Toxicologia, Faculdade de Ciências Farmacêuticas, Universidade Estadual Paulista, Brazil.
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Srinivas NR. Role of Stereoselective Assays in Bioequivalence Studies of Racemic Drugs: Have We Reached a Consensus? J Clin Pharmacol 2013; 44:115-9. [PMID: 14747419 DOI: 10.1177/0091270003262098] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The existence of stereoselectivity in metabolism and drug disposition, coupled with the existence of genetic polymorphisms and modulation of enantiomeric kinetics via special delivery systems, provides some compulsion to assess bioequivalence using stereoselective data. However, examination of the literature suggests that nonstereoselective data are commonly used for the bioequivalence assessment of drug racemates.
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Affiliation(s)
- Nuggehally R Srinivas
- Dr. Reddy's Research Laboratories-Discovery Research, Bollaram Road, Miyapur, Hyderabad, India
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LEES P, HUNTER RP, REEVES PT, TOUTAIN PL. Pharmacokinetics and pharmacodynamics of stereoisomeric drugs with particular reference to bioequivalence determination. J Vet Pharmacol Ther 2012; 35 Suppl 1:17-29. [DOI: 10.1111/j.1365-2885.2012.01367.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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Bioequivalence of venlafaxine modified-release capsule revisited with an innovative approach using experimental and predictive models. Bioanalysis 2011; 3:31-43. [DOI: 10.4155/bio.10.129] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Background: To evaluate the venlafaxine:O-desmethyl venlafaxine (active metabolite) in vivo formation ratio (MR) in three independent bioequivalence (BE) studies consisting of single-dosed (under fasted and fed conditions) and multiple-dosed clinical trials on healthy subjects. The pooled data pharmacokinetic (PK) analysis demonstrates a model to conduct enantiomer/racemate/active metabolite bioanalysis for regulatory submission of bioavailability/bioequivalence (BA/BE) studies using an interesting MR concept. Results: BE was established for all three studies. Moreover, the venlafaxine:O-desmethyl venlafaxine MR for Cmax and AUClast differed by more than 50% for fasted and fed single-dosed studies, while pooled data analysis found the MR for Cmax to be approximately 0.63 and the AUC to be approximately 0.36 for both test and reference drugs. However, negligible variation was observed for both rate and extent of drug and active metabolite absorption into the systemic circulation at steady state, as the MR for both Cmax and AUC was approximately 0.62. Conclusions: The applications/consequences of the above results are immense. First, an achiral assay for venlafaxine and O-desmethyl venlafaxine estimation in human plasma has been justified for the regulatory acceptance of BA/BE studies, supported with both single- and multiple-dosed PK data showing negligible variation in terms of MR at Cmax. Second, the current investigation shows the MR to be within ±10% when compared with the single-dosed reported study on a western population. Third, the racial effect would not lead to any significant clinical outcome using an interchangeable venlafaxine 150-mg capsule manufactured by Ranbaxy with an Efexor 150-mg capsule manufactured by Wyeth. Furthermore, a decision tree is proposed to evaluate if a racemate or an enantiomer drug and active metabolite bioanalysis should be executed for BA/BE regulatory submission using respective achiral or chiral assays when the drug moiety is a racemate or an enantiomer, formulated in modified-release dosage forms.
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Kasprzyk-Hordern B. Pharmacologically active compounds in the environment and their chirality. Chem Soc Rev 2010; 39:4466-503. [PMID: 20852776 DOI: 10.1039/c000408c] [Citation(s) in RCA: 281] [Impact Index Per Article: 20.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Pharmacologically active compounds including both legally used pharmaceuticals and illicit drugs are potent environmental contaminants. Extensive research has been undertaken over the recent years to understand their environmental fate and toxicity. The one very important phenomenon that has been overlooked by environmental researchers studying the fate of pharmacologically active compounds in the environment is their chirality. Chiral drugs can exist in the form of enantiomers, which have similar physicochemical properties but differ in their biological properties such as distribution, metabolism and excretion, as these processes (due to stereospecific interactions of enantiomers with biological systems) usually favour one enantiomer over the other. Additionally, due to different pharmacological activity, enantiomers of chiral drugs can differ in toxicity. Furthermore, degradation of chiral drugs during wastewater treatment and in the environment can be stereoselective and can lead to chiral products of varied toxicity. The distribution of different enantiomers of the same chiral drug in the aquatic environment and biota can also be stereoselective. Biological processes can lead to stereoselective enrichment or depletion of the enantiomeric composition of chiral drugs. As a result the very same drug might reveal different activity and toxicity and this will depend on its origin and exposure to several factors governing its fate in the environment. In this critical review a discussion of the importance of chirality of pharmacologically active compounds in the environmental context is undertaken and suggestions for directions in further research are made. Several groups of chiral drugs of major environmental relevance are discussed and their pharmacological action and disposition in the body is also outlined as it is a key factor in developing a full understanding of their environmental occurrence, fate and toxicity. This review will be of interest to environmental scientists, especially those interested in issues associated with environmental contamination with pharmacologically active compounds and chiral pollutants. As the review will outline current state of knowledge on chiral drugs, it will be of value to anyone interested in the phenomenon of chirality, chiral drugs, their stereoselective disposition in the body and environmental fate (212 references).
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Affiliation(s)
- Barbara Kasprzyk-Hordern
- University of Huddersfield, Department of Chemical and Biological Sciences, School of Applied Sciences, Queensgate, Huddersfield HD1 3DH, UK.
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Gomez-Paloma L, Bruno I, Cini E, Khochbin S, Rodriquez M, Taddei M, Terracciano S, Sadoul K. Design and synthesis of cyclopeptide analogues of the potent histone deacetylase inhibitor FR235222. ChemMedChem 2008; 2:1511-9. [PMID: 17694590 DOI: 10.1002/cmdc.200700095] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Various structurally modified analogues of FR235222 (1), a natural tetrapeptide inhibitor of mammalian histone deacetylases, were prepared in a convergent approach. The design of the compounds was aimed to investigate the effect of structural modifications of the tetrapeptide core involved in enzyme binding in order to overcome some synthetic difficulties connected with the natural product 1. The modifications introduced could also help identify key structural features involved in the mechanism of action of these compounds. The prepared molecules were subjected to in vitro pharmacological tests, and their potency was tested on cultured cells. Two of the components of the array were found to be more potent than the parent compound 1 and almost as efficient as trichostatin A (TSA). These results demonstrate that it is possible to synthesize highly active cyclic tetrapeptides using commercially available amino acids (with the exception of 2-amino-8-oxodecanoic acid, Ahoda). The nature of the residue in the second position of the cyclic peptide and the stereochemistry of the Ahoda tail are important for the inhibitory activity of this class of cyclic tetrapeptide analogues.
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Affiliation(s)
- Luigi Gomez-Paloma
- Dipartimento di Scienze Farmaceutiche, Università di Salerno, Via Ponte don Melillo, 84084 Fisciano (Salerno), Italy
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Eradiri O, Sista S, Lai JCK, Nguyen OH, Silverstone PH. Single- and multiple-dose bioequivalence of two once-daily tramadol formulations using stereospecific analysis of tramadol and its demethylated (M1 and M5) metabolites. Curr Med Res Opin 2007; 23:1593-604. [PMID: 17559753 DOI: 10.1185/030079907x199781] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
OBJECTIVE To assess bioequivalence of two once-daily formulations of tramadol (T) as well as delineate pharmacokinetics of its enantiomers and those of its main metabolites after single- and multiple-dose administration. METHODS Single- and multiple-dose studies were conducted separately each in 48 healthy volunteers using an open-label, randomized, crossover design. Subjects received the 200 mg test (Tramadolor) and reference (Ultram ER) formulations in a randomized manner separated by a 7-day washout period once (single-dose study) or once daily for 7 days (multiple-dose study). Blood was sampled on days 1-2 (single-dose) or days 4-7 (multiple-dose), and plasma samples were analyzed using a stereospecific assay for quantitation of individual enantiomers of T and its active O-demethylated (M1) and N,O-demethylated (M5) metabolites. Bioequivalence was assessed using log-transformation and 90% confidence intervals. RESULTS All analytes showed stereoselectivity after single and multiple doses of both products, with average concentrations of (+)-T, (-)-M1, and (-)-M5 exceeding those of their respective antipode. However, a decrease in steady-state oral clearance of T relative to single dose was not stereoselective. In both studies, the formulations were bioequivalent with regard to AUG and Cmax for both enantiomers of all analytes. The Tmax for the reference (10-12 h) was significantly (p < 0.05) longer than that for the test (5-6 h). Degree of fluctuation of T enantiomers after the test was greater than the reference. Both formulations were tolerated relatively well. CONCLUSIONS Tramadolor and Ultram ER were bioequivalent for both enantiomers of T, M1 and M5. It is unlikely there would be any significant clinical differences between the two formulations.
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García-Arieta A, Abad-Santos F, Rodríguez-Martínez MA, Varas-Polo Y, Novalbos J, Laparidis N, Gallego-Sandín S, Orfanidis K, Torrado J. An eutomer/distomer ratio near unity does not justify non-enantiospecific assay methods in bioequivalence studies. Chirality 2005; 17:470-5. [PMID: 16104026 DOI: 10.1002/chir.20186] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
The aim of the present investigation was to compare the pharmacokinetics of two tablet formulations of 600 mg of racemic ibuprofen obtained using enantiospecific and non-enantiospecific assays, in order to explore if chiral assays should be employed in bioequivalence studies of chiral active substances. The stereoselective assay showed that, for both formulations, there was an initial phase where (R)-ibuprofen was the predominant enantiomer followed by a final phase where (S)-ibuprofen was the predominant one. Results from both analytical methods proved that the two formulations were bioequivalent. However, the chiral bioanalytical method detected a larger difference in the eutomer than that showed by the nonchiral bioanalytical method. In conclusion, although the exposure ratios of enantiomers are near unity, the measurement of unresolved ibuprofen alone is not an adequate measure of bioequivalence since it may mask the actual difference in the eutomer exposure among formulations.
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Affiliation(s)
- Alfredo García-Arieta
- Division of Pharmacology and Clinical Evaluation, General Subdirection for Human Use Medicines, Spanish Agency for Medicines and Health Care Products, Madrid, Spain
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Priymenko NMH, Koritz GD, Ferre JP, Laroute VMF, Toutain PL. Influence of Feeding and Analytical Method on the Bioequivalence of a Racemic Drug Undergoing Enantioselective Enterohepatic Recycling. J Pharm Sci 2004; 93:590-600. [PMID: 14762898 DOI: 10.1002/jps.10581] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Two crossover bioequivalence trials of an enantioselectively enterohepatic recycled drug, carprofen, were conducted in dogs with the same racemic oral formulation to determine: (i) the influence of feeding patterns, and (ii) the effect of the analytical method (enantioselective vs non-enantioselective) on the statistical power of the trials. The first trial was conducted with a standard feeding protocol and the second with a special feeding protocol selected to ensure constant biliary flow into the duodenum. Using a non-enantioselective technique, 90% confidence intervals provided conclusions of bioequivalence in 100% of the cases for both area under the plasma concentration versus time curve (AUC) and maximum plasma drug concentration (Cmax) with the special feeding protocol, but only 50% for AUC and 13% for Cmax with the standard feeding protocol, suggesting that a feeding pattern that diminishes plasma drug concentration rebound for an enterohepatically recycled drug increases the power of a bioequivalence trial. Whatever the feeding protocol, an enantioselective method decreased the power of the trials for AUC but increased the power of the trials for Cmax. For an enterohepatically recycled drug, feeding pattern can influence the power of a bioequivalence trial, and the analytical technique that provides the greatest power depends on the assessed bioequivalence parameter and the feeding pattern.
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Affiliation(s)
- Nathalie M-H Priymenko
- Ecole Nationale Vétérinaire de Toulouse, UMR 181 INRA de Physiopathologie et Toxicologie Expérimentales, 23 Chemin des Capelles, 31076 Toulouse Cedex 3, France
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10
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Nobilis M, Kopecký J, Kvetina J, Chládek J, Svoboda Z, Vorísek V, Perlík F, Pour M, Kunes J. High-performance liquid chromatographic determination of tramadol and its O-desmethylated metabolite in blood plasma. Application to a bioequivalence study in humans. J Chromatogr A 2002; 949:11-22. [PMID: 11999728 DOI: 10.1016/s0021-9673(01)01567-9] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Simultaneous HPLC determination of the analgetic agent tramadol, its major pharmacodynamically active metabolite (O-desmethyltramadol) in human plasma is described. Simple methods for the preparation of the standard of the above-mentioned tramadol metabolite and N1,N1-dimethylsulfanilamide (used as the internal standard) are also presented. The analytical procedure involved a simple liquid-liquid extraction of the analytes from the plasma under the conditions described previously. HPLC analysis was performed on a 250x4 mm chromatographic column with LiChrospher 60 RP-selectB 5-microm (Merck) and consists of an analytical period where the mobile phase acetonitrile-0.01 M phosphate buffer, pH 2.8 (3:7, v/v) was used, and of a subsequent wash-out period where the plasmatic ballast compounds were eluted from the column using acetonitrile-ultra-high-quality water (8:2, v/v). The whole analysis, including the equilibration preceding the initial analytical conditions lasted 19 min. Fluorescence detection (lambda(ex) 202 nm/lambda(em) 296 nm for tramadol and its metabolite, lambda(ex) 264 nm/lambda(em) 344 nm for N1,N1-dimethylsulfanilamide) was used. The validated analytical method was applied to pharmacokinetic studies of tramadol in human volunteers.
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Affiliation(s)
- M Nobilis
- Institute of Experimental Biopharmaceutics, Joint Research Center of Academy of Sciences of the Czech Republic and PRO.MED.CS Praha a.s., Hradec Králové
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11
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Boni JR, Korth-Bradley JM, Richards LS, Chiang ST, Hicks DR, Benet LZ. Chiral bioequivalence: effect of absorption rate on racemic etodolac. Clin Pharmacokinet 2000; 39:459-69. [PMID: 11192477 DOI: 10.2165/00003088-200039060-00006] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
BACKGROUND For many racemic drugs, bioequivalence assessment based on isomer-nonspecific assays is appropriate because enantiomeric area under the concentration-time curve (AUC) exposure ratios are close to unity. Use of nonspecific methods in cases in which the ratio is substantially greater or less than 1, however, may obscure real therapeutic differences among formulations, especially if the enantiomers exhibit differing pharmacological potencies. OBJECTIVE To examine the influence of absorption rate on etodolac bioequivalence as measured by total [(R,S)-] and (S)-etodolac. DESIGN Single dose, 3-period, crossover, pharmacokinetic study in 24 healthy volunteers in which the administration rate of etodolac was varied. METHODS Participants received etodolac 400mg in solution, given as a single dose over 1 minute or as divided doses over 30 and 90 minutes. Unresolved and enantiomer concentrations of etodolac were measured by a validated HPLC assay. The enantiomer ratio was similarly measured by HPLC. RESULTS Bioequivalence parameters derived for both unresolved and (S)etodolac indicate that peak plasma drug concentration (Cmax) was not bioequivalent. By delaying absorption, bioequivalence was lost. CONCLUSIONS Collectively, these data demonstrate that bioequivalence between 2 products of etodolac based on enantiomerically nonspecific criteria alone may not generalise to the pharmacologically relevant (S)-enantiomer. This suggests that enantiospecific assays are necessary for bioequivalence assessments.
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Affiliation(s)
- J R Boni
- Department of Clinical Pharmacokinetics, Wyeth-Ayerst Research, Radnor, Pennsylvania 19101-1245, USA.
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Breithaupt-Grögler K, Niebch G, Schneider E, Erb K, Hermann R, Blume HH, Schug BS, Belz GG. Dose-proportionality of oral thioctic acid--coincidence of assessments via pooled plasma and individual data. Eur J Pharm Sci 1999; 8:57-65. [PMID: 10072479 DOI: 10.1016/s0928-0987(98)00061-x] [Citation(s) in RCA: 76] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Thioctic acid (TA), a racemate of R-(+)- and S-(-)-enantiomers of alpha-lipoic acid, acts as a powerful lipophilic, free-radical scavenger and is used in the treatment of diabetic neuropathy. This trial investigated the dose-linearity of enantiomer pharmacokinetics following the oral administration of single doses of 50 to 600 mg TA (formulation provided by ASTA (Medica)) in healthy volunteers. TA enantiomer concentrations in individual and pooled plasma samples were determined using enantioselective, high-performance liquid chromatography. TA was rapidly absorbed (tmax, 0.5 to 1 h). Maximum plasma concentrations (Cmax) of the R-(+)-enantiomer were about 40-50% higher than those of the S-(-)-enantiomer (50 mg: 135.45 ng/ml R-(+)-TA, 67.83 ng/ml S-(-)-TA; 600 mg: 1812.32 ng/ml R-(+)-TA, 978.20 ng/ml S-(-)-TA; geometric means). The decline observed in the plasma concentration was steep (t1/2, 0.5 h). The dose-linearity and proportionality of pharmacokinetic parameters could be demonstrated on an intra-individual basis and for the group geometric means. An analysis of pooled plasma samples proved to be a suitable means for deriving reliable first-sight results prior to individual assessments.
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Affiliation(s)
- K Breithaupt-Grögler
- Center for Cardiovascular Pharmacology, Mathildenstrasse 8, 55116, Mainz, Germany
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Addison RS, Franklin ME, Hooper WD. Sensitive, high-throughput gas chromatographic-mass spectrometric assay for fluoxetine and norfluoxetine in human plasma and its application to pharmacokinetic studies. JOURNAL OF CHROMATOGRAPHY. B, BIOMEDICAL SCIENCES AND APPLICATIONS 1998; 716:153-60. [PMID: 9824228 DOI: 10.1016/s0378-4347(98)00285-0] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
A sensitive, robust gas chromatographic-mass spectrometric assay suitable for use in pharmacokinetic or bioequivalence studies is presented for the selective serotonin reuptake inhibitor, fluoxetine, and its major metabolite, norfluoxetine (N-desmethylfluoxetine). This method employs solid-phase extraction followed by acetylation with trifluoroacetic anhydride and analysis of the derivatives using selected ion monitoring. The lower limit of quantification was 1.0 ng/ml, and the assay was linear for both analytes from 1 to 100 ng/ml. Mean recoveries following solid-phase extraction at concentrations of 5.0, 20 and 100 ng/ml were 91% (fluoxetine) and 87% (norfluoxetine). Assay precision (as mean RSD) and accuracy (as mean relative error) for both analytes were tested at the same three nominal concentrations and were found to be within 10% in all cases. Analysis of fluoxetine concentrations in plasma samples from 18 volunteers following administration of a single 40 mg dose of fluoxetine provided the following pharmacokinetic data (mean+/-SD): Cmax, 32.73+/-9.21 ng/ml; AUC0-infinity, 1627+/-1372 ng/ml h; Tmax, 3.08 h (median); ke, 0.022+/-0.007 h(-1); elimination half-life, 37.69+/-21.70 h.
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Affiliation(s)
- R S Addison
- Centre for Studies in Drug Disposition, Department of Medicine, The University of Queensland, Royal Brisbane Hospital, Australia
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Midha KK, McKay G, Rawson MJ, Hubbard JW. The impact of stereoisomerism in bioequivalence studies. J Pharm Sci 1998; 87:797-802. [PMID: 9649345 DOI: 10.1021/js9703683] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- K K Midha
- Drug Metabolism Drug Disposition Group, College of Pharmacy and Nutrition, University of Saskatchewan, 110 Science Place, Saskatoon, Saskatchewan, Canada, S7N 5C9
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Cooper SA, Reynolds DC, Reynolds B, Hersh EV. Analgesic efficacy and safety of (R)- ketoprofen in postoperative dental pain. J Clin Pharmacol 1998; 38:11S-18S. [PMID: 9549654 DOI: 10.1002/j.1552-4604.1998.tb04412.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
This double-blind, randomized, parallel-group study compared the analgesic efficacy and safety of single doses of (R)- ketoprofen 25 mg and 100 mg to that of acetaminophen 1,000 mg and placebo in 177 patients experiencing moderate to severe pain after surgical removal of their impacted third molars. Both (R)- ketoprofen 100 mg and acetaminophen 1,000 mg were significantly (P < 0.05) more efficacious than placebo for all summary analgesic measures. Other than a more rapid analgesic onset (45 minutes versus 60 minutes) for acetaminophen 1,000 mg, (R)- ketoprofen 100 mg and acetaminophen 1,000 mg were statistically equivalent to each other. The 25 mg dose of (R)- ketoprofen appeared to approach the analgesic threshold dose, being numerically but not statistically superior to placebo for all summary measures. There were no serious adverse events observed in this study, with the overall incidence of side effects being somewhat less in the (R)- ketoprofen groups than in the acetaminophen 1,000 mg group. (R)- Ketoprofen possesses analgesic activity and an acceptable side-effect profile in the oral surgery pain model.
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Affiliation(s)
- S A Cooper
- Department of Clinical Research, Whitehall-Robins Healthcare, Madison, NJ, USA
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