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Vashistha VK, Kumar A. Stereochemical facets of clinical β‐blockers: An overview. Chirality 2020; 32:722-735. [DOI: 10.1002/chir.23200] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2019] [Revised: 02/09/2020] [Accepted: 02/11/2020] [Indexed: 11/07/2022]
Affiliation(s)
| | - Anuj Kumar
- Department of ChemistryGLA University Mathura Uttar Pradesh India
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Survey of Pharmacological Activity and Pharmacokinetics of Selected β-Adrenergic Blockers in Regard to Their Stereochemistry. APPLIED SCIENCES-BASEL 2019. [DOI: 10.3390/app9040625] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
The present survey concentrates on pharmacodynamics and pharmacokinetics of selected β-adrenergic blockers from the point of view of their stereochemistry. It could be shown that the activity in the arylaminoethanol and aryloxyaminopropanol group of β-blockers is higher in their (–)-enantiomers as compared with the (+)-enantiomers. The stereoisomers differ also in other types of bioactivity as well as in toxicity. The particular pharmacokinetic stages such as resorption, distribution, and metabolism are discussed in regard to their stereochemistry.
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Pham CV, Baek JS, Park JH, Jung SH, Kang JS, Cho CW. A thorough analysis of the effect of surfactant/s on the solubility and pharmacokinetics of (S)-zaltoprofen. Asian J Pharm Sci 2018; 14:435-444. [PMID: 32104472 PMCID: PMC7032178 DOI: 10.1016/j.ajps.2018.10.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2018] [Revised: 08/21/2018] [Accepted: 10/02/2018] [Indexed: 10/27/2022] Open
Abstract
Until now, there are no publications about the preformulation studies on (S)-zaltoprofen ((S)-ZPF). Hence, we first investigated the solubility of (S)-ZPF, screened solubilizers and performed the pharmacokinetic study of (S)-ZPF in the presence of the solubilizers. The measurement of the solubility of (S)-ZPF in 26 different solvents was carried out, including d-alpha tocopheryl polyethylene glycol 1000 succinate (TPGS), 2-hydroxypropyl-β-cyclodextrin (HPCD), and mixtures of individual solvent. The plasma concentration of (S)-ZPF and the amount of (S)-ZPF retained in stomach were determined after oral (35.0 mg/kg) and intravenous (5.0 mg/kg) administration. The solubility of (S)-ZPF showed an increase of 484-fold in TPGS compared to its aqueous solubility. There was a significant increase of AUC0-24 h for pure (S)-ZPF in the TPGS group (813.59 ± 64.17 µg⋅h/ml) in comparison with AUC0-24 h in the HPCD group (595.57 ± 71.76 µg⋅h/ml) and water group (465.57 ± 90.89 µg⋅h/ml). In addition, the Tmax of (S)-ZPF in the TPGS group was 2 h, much faster than that in the HPCD or water groups (5.50 or 5.67 h, respectively). This suggested that TPGS played a significant role in the increase of solubility and bioavailability of (S)-ZPF.
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Affiliation(s)
- Cuong Viet Pham
- College of Pharmacy and Institute of Drug Research and Development, Chungnam National University, Daejeon 34134, Republic of Korea
| | - Jong-Suep Baek
- College of Pharmacy and Institute of Drug Research and Development, Chungnam National University, Daejeon 34134, Republic of Korea
| | - Jong-Hun Park
- Department of Herbology, College of Korean Medicine, Dongguk University, Gyeongju 38066, Republic of Korea
| | - Sang-Hun Jung
- College of Pharmacy and Institute of Drug Research and Development, Chungnam National University, Daejeon 34134, Republic of Korea
| | - Jong-Seong Kang
- College of Pharmacy and Institute of Drug Research and Development, Chungnam National University, Daejeon 34134, Republic of Korea
| | - Cheong-Weon Cho
- College of Pharmacy and Institute of Drug Research and Development, Chungnam National University, Daejeon 34134, Republic of Korea
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4
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Efficient resolution of profen ethyl ester racemates by engineered Yarrowia lipolytica Lip2p lipase. ACTA ACUST UNITED AC 2017. [DOI: 10.1016/j.tetasy.2017.01.014] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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Rainsford KD, Parke AL, Clifford-Rashotte M, Kean WF. Therapy and pharmacological properties of hydroxychloroquine and chloroquine in treatment of systemic lupus erythematosus, rheumatoid arthritis and related diseases. Inflammopharmacology 2015; 23:231-69. [PMID: 26246395 DOI: 10.1007/s10787-015-0239-y] [Citation(s) in RCA: 349] [Impact Index Per Article: 38.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2015] [Accepted: 06/23/2015] [Indexed: 12/15/2022]
Abstract
OBJECTIVES This review examines the pharmacokinetics, modes of action and therapeutic properties of the anti-malarial drugs, hydroxychloroquine (HCQ) and chloroquine (CQ), in the treatment of systemic lupus erythematosus (SLE), rheumatoid arthritis (RA) and related conditions, as well as osteoarthritis (OA). KEY FINDINGS Both HCQ and CQ have historically been employed successfully for the treatment of SLE and RA for over 70 years. HCQ has been used extensively for SLE where it has a good reputation for controlling the dermatological complications in SLE. It has also been reported to effectively control the symptoms of Sjøgren's syndrome, as well as preventing thrombosis in phospholipid antibody (aPL) syndrome. In RA and SLE, HCQ is preferred because of the lower incidence of gastrointestinal adverse reactions compared with CQ and it might have a lower risk of ocular adverse reactions. There is increasing evidence that HCQ may reduce atherosclerosis and risks of cardiovascular disease in rheumatic patients. Both HCQ and CQ have been shown to improve glycaemia and reduce the risks of type II diabetes mellitus. Although both HCQ and CQ are effective in low-moderate RA, HCQ is now preferred as part of combination therapy for more severe disease. The advantages of combination therapy are that the doses of the individual drugs may be lowered so reducing adverse reactions. Both HCQ and CQ are diastereoisomers, have basic properties and are given as the sulphate and phosphate salts. While being relatively well absorbed orally and with good bioavailability, they have long and variable plasma terminal elimination half-lives (approximately 40-60 days). This reflects their high volume of distribution, V D (HCQ 44,000L; CQ 65,000L) which extends into aqueous compartments, long mean residence time (HCQ 1300 h; CQ 900 h) and with about half the drugs (metabolites) undergoing renal clearance. The strong binding to melanin reflects the ocular injury and dermatological properties of these drugs. The consensus is that the occurrence of ocular adverse reactions can be minimised by close attention to the dose (which should be set on a body weight basis) with regular (e.g. quarterly) retinal examination. Although HCQ and CQ can pass through the placenta, the use of these drugs during pregnancy does not appear to risk harm to the baby and might be beneficial to the mother with SLE and her child by controlling the SLE disease activity, which is known to be an important factor affecting pregnancy outcome. The modes of action of HCQ and CQ in these arthritides represent somewhat of an enigma. Undoubtedly, these drugs have multiple actions related, in part, their ability to accumulate in lysosomes and autophagosomes of phagocytic cells as well as affecting MHC Class II expression and antigen presentation; actions of the production of pro-inflammatory cytokines [e.g. interleukin-1 (IL-1) tumour necrosis factor-α (TNFα)]; control of toll-like receptor-9 activation; and leucocyte generation of reactive oxygen species (ROS); i.e. antioxidant activity. The actions of these drugs on T and B cells are less clear but may depend on these leucocyte-mediated actions. Anti-malarials also protect against cytokine-mediated cartilage resorption. This and other actions may underlie the potential benefits in treating OA. The exact relationships of these various actions, mostly determined in vitro, have not been specifically defined in vivo or ex vivo in relation to clinical efficacy. OUTCOMES HCQ and CQ have a good reputation for being effective and relatively safe treatments in SLE, mild-moderate RA and Sjøgren's syndrome. There is need for (a) more information on their mode of action in relation to the control of these diseases, (b) scope for developing formulations that have improved pharmacokinetic and therapeutic properties and safety, and (c) further exploring their use in drug combinations not only with other disease modifying agents but also with biologics.
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Affiliation(s)
- K D Rainsford
- Biomedical Research Centre, Sheffield Hallam University, Howard Street, Sheffield, S1 1WB, UK
| | - Ann L Parke
- Department of Rheumatology, St Francis Hospital and Medical Center, Hartford, CT, 06105, USA
| | | | - W F Kean
- Department of Medicine (Rheumatology), McMaster University Faculty of Health Sciences, Hamilton, ON, L8S 4K9, Canada.
- Department of Medicine (Rheumatology), McMaster University Faculty of Health Sciences, Suite #708, 1 Young Street, Hamilton, ON, L8N 1T8, Canada.
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Solubility and Some Crystallization Properties of Conglomerate Forming Chiral Drug Guaifenesin in Water. J Pharm Sci 2014; 103:3176-82. [DOI: 10.1002/jps.24104] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2014] [Revised: 06/17/2014] [Accepted: 07/11/2014] [Indexed: 02/05/2023]
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7
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Hotha KK, Roychowdhury S, Mullangi R, Ravindranath LK. Rapid quantification of amlodipine enantiomers in human plasma by LC-MS/MS: application to a clinical pharmacokinetic study. Biomed Chromatogr 2013; 27:1192-9. [DOI: 10.1002/bmc.2926] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2013] [Accepted: 03/24/2013] [Indexed: 11/08/2022]
Affiliation(s)
- Kishore Kumar Hotha
- Analytical Research and Development; Novel Laboratories Inc.; Somerset; NJ; 08873; USA
| | - Swapan Roychowdhury
- Analytical Research and Development; Novel Laboratories Inc.; Somerset; NJ; 08873; USA
| | - Ramesh Mullangi
- Jubilant Biosys Ltd; Industrial Suburb; Yeshwanthpur; Bangalore; 560 022; India
| | - L. K. Ravindranath
- Department of Chemistry; S.K. University; Anantapur; 515 001; A.P; India
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Hunter RP, DeRidder E, Lucas A, Smedley KO, Yordy DW. How do you define equivalence of the API of biomass products? J Vet Pharmacol Ther 2012; 35 Suppl 1:99-101. [PMID: 22413797 DOI: 10.1111/j.1365-2885.2012.01374.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- R P Hunter
- Elanco Animal Health, 2500 Innovation Way, Greenfield, IN, USA.
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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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Wang RQ, Ong TT, Ng SC. Chemically bonded cationic β-cyclodextrin derivatives and their applications in supercritical fluid chromatography. J Chromatogr A 2011; 1224:97-103. [PMID: 22236564 DOI: 10.1016/j.chroma.2011.12.053] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2011] [Revised: 12/13/2011] [Accepted: 12/15/2011] [Indexed: 10/14/2022]
Abstract
Cationic β-cyclodextrin (CD) perphenylcarbamoylated derivatives were chemically bonded onto vinylized silica using a radical co-polymerization reaction. The derived materials were used as chiral stationary phases (CSP) in supercritical fluid chromatography (SFC). Enantioseparations were successfully demonstrated on 14 racemates encompassing flavanones, thiazides and amino acid derivatives. The electrostatic force between the analytes and the cationic moiety on β-CD derivative was found to be important for retention and enantioseparation of the racemates. Aromatic cationic moiety on β-CD enabled better enantioseparations than aliphatic cationic moiety. It was also found that the presence of acid additives would result in lower retention of the analytes but often assist the chiral resolutions.
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Affiliation(s)
- Ren-Qi Wang
- Division of Chemical and Biomolecular Engineering, College of Engineering, Nanyang Technological University, 62 Nanyang Drive, Singapore 637459, Singapore
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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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MARTINEZ MN, HUNTER RP. Current challenges facing the determination of product bioequivalence in veterinary medicine. J Vet Pharmacol Ther 2010; 33:418-33. [DOI: 10.1111/j.1365-2885.2010.01180.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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Singh A, Myerson AS. Chiral Self Assembled Monolayers as Resolving Auxiliaries in the Crystallization of Valine. J Pharm Sci 2010; 99:3931-40. [DOI: 10.1002/jps.22237] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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Zeng A, Wang C, Yuan B, Yang G, Fu Q. The influence of chirality, physicochemical properties, and permeation enhancers on the transdermal permeation of amlodipine across rat skin. Drug Dev Ind Pharm 2010; 36:724-34. [DOI: 10.3109/03639040903460438] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Abstract
Although chloroquine, hydroxychloroquine and quinacrine were originally developed for the treatment of malaria, these medications have been used to treat skin disease for over 50 years. Recent clinical data have confirmed the usefulness of these medications for the treatment of lupus erythematosus. Current research has further enhanced our understanding of the pharmacologic mechanisms of action of these drugs involving inhibition of endosomal toll-like receptor (TLR) signaling limiting B cell and dendritic cell activation. With this understanding, the use of these medications in dermatology is broadening. This article highlights the different antimalarials used within dermatology through their pharmacologic properties and mechanism of action, as well as indicating their clinical uses. In addition, contraindications, adverse effects, and possible drug interactions of antimalarials are reviewed.
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Affiliation(s)
- Sunil Kalia
- Department of Dermatology and Skin Science, University of British Columbia, Vancouver, BC, Canada
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Yoon S, Kim S, Ryu Y, Kim TD. Identification and characterization of a novel (S)-ketoprofen-specific esterase. Int J Biol Macromol 2007; 41:1-7. [PMID: 17196647 DOI: 10.1016/j.ijbiomac.2006.11.010] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2006] [Revised: 11/20/2006] [Accepted: 11/20/2006] [Indexed: 11/25/2022]
Abstract
A new (S)-ketoprofen specific esterase (EST-Y29) was identified from a metagenome library from environmental samples, which showed homologies with class C-beta lactamase, penicillin binding protein, and other lipases/esterases. In order to investigate the biochemical and biophysical properties, the recombinant protein was overexpressed, purified to homogeneity, and characterized. This EST-Y29 has high catalytic activity against p-nitrophenyl esters of short fatty acids (C(2) and C(4)) and alpha-naphthyl acetate with activation energy of 30.4 kJ/mol. We have further characterized EST-Y29 using high performance liquid chromatography (HPLC), circular dichroism (CD), dynamic light scattering (DLS) and size exclusion chromatography (SEC).
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Affiliation(s)
- Sangyoung Yoon
- Department of Biological and Molecular Engineering, College of Engineering, Ajou University, Suwon 443-749, South Korea
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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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Welage LS, Kirking DM, Ascione FJ, Gaither CA. Understanding the scientific issues embedded in the generic drug approval process. JOURNAL OF THE AMERICAN PHARMACEUTICAL ASSOCIATION (WASHINGTON, D.C. : 1996) 2001; 41:856-67. [PMID: 11765111 DOI: 10.1016/s1086-5802(16)31327-4] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
OBJECTIVE To review the major scientific issues embedded in the generic drug approval process. DATA SOURCES Articles indexed initially under terms such as generic medications, generic drugs, bioequivalence, and bioinequivalence. These terms were used to search indexing services such as MEDLINE, International Pharmaceutical Abstracts, CINAHL (a database of nursing and allied health literature), and Science Citation Index. Additional data sources included the Code of Federal Regulations and regulatory guidances from the Food and Drug Administration (FDA) Center for Drug Evaluation and Research. STUDY SELECTION Performed by the authors. DATA EXTRACTION Not applicable. DATA SYNTHESIS Despite the fact that regulations regarding bioequivalence have been in place for more than 20 years, controversies over bioequivalence continue to arise. Consensus on many of these issues is driving the development of new FDA guidances regarding bioequivalence. Still, despite the issuance of new guidance and consensus building among scientists, many clinicians and consumers remain uninformed regarding the scientific basis for establishing bioequivalence and the generic drug approval process in general. Although some have suggested that the generic drug approval process is flawed, overall, it appears that the process works. CONCLUSION Understanding the generic drug approval process and the issues surrounding bioequivalence is of paramount importance to both clinicians and scientists.
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Affiliation(s)
- L S Welage
- Department of Clinical Sciences, College of Pharmacy, University of Michigan Health System, Ann Arbor 48109-1065, USA.
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Bui TH, Fernandez C, Vu K, Nguyen KH, Thuillier A, Farinotti R, Arnaud P, Gimenez F. Stereospecific versus nonstereospecific assessments for the bioequivalence of two formulations of racemic chlorpheniramine. Chirality 2000; 12:599-605. [PMID: 10897096 DOI: 10.1002/1520-636x(2000)12:8<599::aid-chir1>3.0.co;2-s] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Chlorpheniramine (chlorphenamine, CPAM) is a racemic antihistaminic H1 drug containing two enantiomers. The aim of this study was to assess the bioequivalence of two formulations (reference and Vietnamese-tested formulation) of racemic chlorpheniramine combined with phenylpropanolamine in an open-labeled, randomized, crossover two-period study, after administration of 8 mg of racemic chlorpheniramine in 12 healthy Vietnamese subjects. First, dissolution of both formulations was tested in vitro according to USP requirements. Then the 12 subjects received both formulations after an overnight fast and a 7-day wash-out period. Plasma samples were collected up to 168 h. Plasma concentrations of total chlorpheniramine and its individual enantiomers were determined with a validated chiral HPLC method and pharmacokinetic parameters were estimated using model-independent analysis. For the reference formulation, Cmax and AUC values were higher for (+)S-chlorpheniramine ((+)S-CPAM) compared to (-)R-chlorpheniramine ((-)R-CPAM) (13.3 vs. 6.8 ng/ml and 409 vs. 222 ng/ml/h, respectively) while Clt/F and Vd/F were lower (9.8 vs. 17.6 l/h and 321 vs. 627 l, respectively). No difference was observed for Tmax, t(1/2), and MRT. Pharmacokinetic parameters were similar for the reference and the Vietnamese-tested formulation. Bioequivalence was assessed by Schuirmann test, as recommended by the current FDA and European Community criteria. Dissolution tests showed that both formulations were equivalent. A nonstereospecific, but not a stereospecific, approach indicated bioequivalence between the formulations.
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Affiliation(s)
- T H Bui
- Pitié Salpêtrière Hospital, Pharmacy, Paris, France
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