101
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Ahnfelt E, Sjögren E, Axén N, Lennernäs H. A miniaturized in vitro release method for investigating drug-release mechanisms. Int J Pharm 2015; 486:339-49. [PMID: 25843760 DOI: 10.1016/j.ijpharm.2015.03.076] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2015] [Revised: 03/30/2015] [Accepted: 03/31/2015] [Indexed: 10/23/2022]
Abstract
We have evaluated a miniaturized in vitro method, based on the μDISS Profiler™ technique that enables on-line monitoring of drug release from a 21 μl sample with 10 ml of release medium. Four model drugs in eight clinically used formulations, including both solid and non-solid drug delivery systems, were investigated. The acquired data were compared with historical in vitro release data from the same formulations. Use of the Weibull function to describe the in vitro drug-release profiles allowed discrimination between the selected formulations with respect to the drug-release mechanisms. Comparison of the release data from the same formulation in different in vitro set-ups showed that the methodology used can affect the mechanism of in vitro release. We also evaluated the ability of the in vitro methods to predict in vivo activity by comparing simulated plasma concentration-time profiles acquired from the application of the biopharmaceutical software GI-Sim to the in vitro observations. In summary, the simulations based on the miniaturized-method release data predicted the plasma profiles as well as or more accurately than simulations based on the historical release data in 71% of the cases and this miniaturized in vitro method appears to be applicable for both solid and non-solid formulations.
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Affiliation(s)
- E Ahnfelt
- Department of Pharmacy, Uppsala University, Box 580, 751 23 Uppsala, Sweden
| | - E Sjögren
- Department of Pharmacy, Uppsala University, Box 580, 751 23 Uppsala, Sweden
| | - N Axén
- Department of Pharmacy, Uppsala University, Box 580, 751 23 Uppsala, Sweden
| | - H Lennernäs
- Department of Pharmacy, Uppsala University, Box 580, 751 23 Uppsala, Sweden.
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102
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Schönherr D, Wollatz U, Haznar-Garbacz D, Hanke U, Box KJ, Taylor R, Ruiz R, Beato S, Becker D, Weitschies W. Characterisation of selected active agents regarding pKa values, solubility concentrations and pH profiles by SiriusT3. Eur J Pharm Biopharm 2015; 92:155-70. [PMID: 25758123 DOI: 10.1016/j.ejpb.2015.02.028] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2014] [Revised: 02/18/2015] [Accepted: 02/27/2015] [Indexed: 10/23/2022]
Abstract
The aim of this work was to determine pKa values and solubility properties of 34active agents using the SiriusT3 apparatus. The selected drug substances belong to the groups of ACE-inhibitors, β-blockers, antidiabetics and lipid lowering substances. Experimentally obtained pKa and intrinsic solubility values were compared to calculated values (program ACD/ChemSketch) and pKa values to published data as well. Solubility-pH profiles were generated to visualise the substance solubility over the gastrointestinal pH range. The relationship between the solubility characteristic of a substance, its bioavailability and categorisation according to the Biopharmaceutics Classification System (BCS) was examined as well. The results showed a good agreement between experimentally obtained, calculated and published pKa values. The measured and calculated intrinsic solubility values indicated several major deviations. All solubility-pH profiles showed the expected shape and appearance for acids, bases or zwitterionic substances. The obtained results for the pKa and solubility measurements of the examined active agents may help to predict their physicochemical behaviour in vivo, and to understand the bioavailability of the substances according to their BCS categorisation. The easy and reproducible determination of pKa and solubility values makes the SiriusT3 apparatus a useful tool in early stages of drug and formulation development.
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Affiliation(s)
- D Schönherr
- University of Greifswald, Center of Drug Absorption and Transport, Institute of Pharmacy, 17487 Greifswald, Germany
| | - U Wollatz
- University of Greifswald, Center of Drug Absorption and Transport, Institute of Pharmacy, 17487 Greifswald, Germany
| | - D Haznar-Garbacz
- University of Greifswald, Center of Drug Absorption and Transport, Institute of Pharmacy, 17487 Greifswald, Germany
| | - U Hanke
- University of Greifswald, Center of Drug Absorption and Transport, Institute of Pharmacy, 17487 Greifswald, Germany
| | - K J Box
- Sirius Analytical Ltd., Forest Row, East Sussex RH18 5DW, UK
| | - R Taylor
- Sirius Analytical Ltd., Forest Row, East Sussex RH18 5DW, UK
| | - R Ruiz
- Sirius Analytical Ltd., Forest Row, East Sussex RH18 5DW, UK
| | - S Beato
- Novartis Pharma AG, Technical Research & Development, 4056 Basel, Switzerland
| | - D Becker
- Vivo Drug Delivery GmbH, 8832 Wollerau, Switzerland
| | - W Weitschies
- University of Greifswald, Center of Drug Absorption and Transport, Institute of Pharmacy, 17487 Greifswald, Germany.
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103
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Ottaviani G, Wendelspiess S, Alvarez-Sánchez R. Importance of Critical Micellar Concentration for the Prediction of Solubility Enhancement in Biorelevant Media. Mol Pharm 2015; 12:1171-9. [DOI: 10.1021/mp5006992] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- G. Ottaviani
- Roche
Pharmaceutical Research and Early Development, Pharmaceutical Sciences, Roche Innovation Center Shanghai, F. Hoffmann-La Roche Ltd, 720 Cai Lun Road, Building
5 Pudong, Shanghai 201203, China
| | - S. Wendelspiess
- Roche
Pharmaceutical Research and Early Development, Pharmaceutical Sciences, Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd, Grenzacherstrasse 124, 4070 Basel, Switzerland
| | - R. Alvarez-Sánchez
- Roche
Pharmaceutical Research and Early Development, Pharmaceutical Sciences, Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd, Grenzacherstrasse 124, 4070 Basel, Switzerland
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104
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Khadra I, Zhou Z, Dunn C, Wilson CG, Halbert G. Statistical investigation of simulated intestinal fluid composition on the equilibrium solubility of biopharmaceutics classification system class II drugs. Eur J Pharm Sci 2015; 67:65-75. [PMID: 25444845 DOI: 10.1016/j.ejps.2014.10.019] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2014] [Revised: 10/29/2014] [Accepted: 10/29/2014] [Indexed: 11/30/2022]
Abstract
A drug's solubility and dissolution behaviour within the gastrointestinal tract is a key property for successful administration by the oral route and one of the key factors in the biopharmaceutics classification system. This property can be determined by investigating drug solubility in human intestinal fluid (HIF) but this is difficult to obtain and highly variable, which has led to the development of multiple simulated intestinal fluid (SIF) recipes. Using a statistical design of experiment (DoE) technique this paper has investigated the effects and interactions on equilibrium drug solubility of seven typical SIF components (sodium taurocholate, lecithin, sodium phosphate, sodium chloride, pH, pancreatin and sodium oleate) within concentration ranges relevant to human intestinal fluid values. A range of poorly soluble drugs with acidic (naproxen, indomethacin, phenytoin, and piroxicam), basic (aprepitant, carvedilol, zafirlukast, tadalafil) or neutral (fenofibrate, griseofulvin, felodipine and probucol) properties have been investigated. The equilibrium solubility results determined are comparable with literature studies of the drugs in either HIF or SIF indicating that the DoE is operating in the correct space. With the exception of pancreatin, all of the factors individually had a statistically significant influence on equilibrium solubility with variations in magnitude of effect between the acidic and basic or neutral compounds and drug specific interactions were evident. Interestingly for the neutral compounds pH was the factor with the second largest solubility effect. Around one third of all the possible factor combinations showed a significant influence on equilibrium solubility with variations in interaction significance and magnitude of effect between the acidic and basic or neutral compounds. The least number of significant media component interactions were noted for the acidic compounds with three and the greatest for the neutral compounds at seven, with again drug specific effects evident. This indicates that a drug's equilibrium solubility in SIF is influenced depending upon drug type by between eight to fourteen individual or combinations of media components with some of these drug specific. This illustrates the complex nature of these fluids and provides for individual drugs a visualisation of the possible solubility envelope within the gastrointestinal tract, which may be of importance for modelling in vivo behaviour. In addition the results indicate that the design of experiment approach can be employed to provide greater detail of drug solubility behaviour, possible drug specific interactions and influence of variations in gastrointestinal media components due to disease. The approach is also feasible and amenable to adaptation for high throughput screening of drug candidates.
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Affiliation(s)
- Ibrahim Khadra
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, 161 Cathedral Street, Glasgow G4 0RE, United Kingdom
| | - Zhou Zhou
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, 161 Cathedral Street, Glasgow G4 0RE, United Kingdom.
| | - Claire Dunn
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, 161 Cathedral Street, Glasgow G4 0RE, United Kingdom
| | - Clive G Wilson
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, 161 Cathedral Street, Glasgow G4 0RE, United Kingdom
| | - Gavin Halbert
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, 161 Cathedral Street, Glasgow G4 0RE, United Kingdom
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105
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Martinez MN, Fahmy R. Demonstrating comparative in vitro bioequivalence for animal drug products through chemistry and manufacturing controls and physicochemical characterization: a proposal. AAPS JOURNAL 2015; 17:307-12. [PMID: 25609223 DOI: 10.1208/s12248-014-9702-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2014] [Accepted: 11/10/2014] [Indexed: 11/30/2022]
Abstract
The assessment of in vivo bioequivalence (BE) of nonsystemically absorbed drug products has been a longstanding challenge facing drug manufacturers and regulators of human or animal health products. Typically, in situations where blood level BE studies are not feasible, clinical endpoint BE trials have provided the only option for generating interproduct comparisons. Given the imprecision and logistic challenges associated with these studies, there has been an effort to identify alternative pathways that can reliably ensure the equivalence of product performance and quality. This commentary provides a proposal for an in vitro approach for evaluating the in vivo BE of veterinary drug products that are either nonsystemically absorbed or that act both locally and systemically but where the local site of action is proximal to the absorption window. The assumption underlying this approach is that equivalence in product physicochemical attributes and in vitro product performance translates to equivalence in product in vivo behavior. For sponsors with a right of reference to underlying safety and effectiveness data, this approach could be used to support pre and post-approval changes. When comparing a generic test product to the pioneer (reference listed new animal drug, RLNAD) product, a demonstration of sameness across a battery of in vitro test procedures could be used to confirm that the test and RLNAD products are bioequivalent.
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Affiliation(s)
- Marilyn N Martinez
- USFDA Center for Veterinary Medicine, Office of New Animal Drug Evaluation, 7500 Standish Place, HFV-100, Rockville, Maryland, 20855, USA,
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106
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Yang B, Wu C, Ji B, Ai X, Kuang X, Wu M, Sun M, Luo C, He Z, Sun J. The biorelevant concentration of Tween 80 solution is a simple alternative medium to simulated fasted state intestinal fluid. RSC Adv 2015. [DOI: 10.1039/c5ra17674c] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The aim of the present study is to investigate whether the use of the biorelevant concentration of conventional surfactants as an alternative medium to simulated fasted state intestinal fluid for drugs with different acid–base properties is feasible.
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Affiliation(s)
- Bin Yang
- Department of Pharmaceutics
- School of Pharmacy
- Shenyang Pharmaceutical University
- China
| | - Chunnuan Wu
- Department of Pharmacy
- Tianjin Medical University Cancer Institute and Hospital
- China
| | - Bin Ji
- Department of Pharmaceutical Analysis
- School of Pharmacy
- Shenyang Pharmaceutical University
- China
| | - Xiaoyu Ai
- College of Pharmacy
- Nankai University
- China
| | - Xiao Kuang
- Department of Pharmaceutics
- School of Pharmacy
- Shenyang Pharmaceutical University
- China
| | - Mingrui Wu
- Department of Pharmaceutics
- School of Pharmacy
- Shenyang Pharmaceutical University
- China
| | - Mengchi Sun
- Department of Pharmaceutics
- School of Pharmacy
- Shenyang Pharmaceutical University
- China
| | - Cong Luo
- Department of Pharmaceutics
- School of Pharmacy
- Shenyang Pharmaceutical University
- China
| | - Zhonggui He
- Department of Pharmaceutics
- School of Pharmacy
- Shenyang Pharmaceutical University
- China
| | - Jin Sun
- Department of Pharmaceutics
- School of Pharmacy
- Shenyang Pharmaceutical University
- China
- Municipal Key Laboratory of Biopharmaceutics
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107
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Fagerberg JH, Sjögren E, Bergström CA. Concomitant intake of alcohol may increase the absorption of poorly soluble drugs. Eur J Pharm Sci 2015; 67:12-20. [DOI: 10.1016/j.ejps.2014.10.017] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2014] [Accepted: 10/23/2014] [Indexed: 10/24/2022]
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108
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Recent advances in delivery systems and therapeutics of cinnarizine: a poorly water soluble drug with absorption window in stomach. JOURNAL OF DRUG DELIVERY 2014; 2014:479246. [PMID: 25478230 PMCID: PMC4247907 DOI: 10.1155/2014/479246] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/23/2014] [Accepted: 10/15/2014] [Indexed: 11/18/2022]
Abstract
Low solubility causing low dissolution in gastrointestinal tract is the major problem for drugs meant for systemic action after oral administration, like cinnarizine. Pharmaceutical products of cinnarizine are commercialized globally as immediate release preparations presenting low absorption with low and erratic bioavailability. Approaches to enhance bioavailability are widely cited in the literature. An attempt has been made to review the bioavailability complications and clinical therapeutics of poorly water soluble drug: cinnarizine. The interest of writing this paper is to summarize the pharmacokinetic limitations of drug with special focus on strategies to improvise bioavailability along with effectiveness of novel dosage forms to circumvent the obstacle. The paper provides insight to the approaches to overcome low and erratic bioavailability of cinnarizine by cyclodextrin complexes and novel dosage forms: self-nanoemulsifying systems and buoyant microparticulates. Nanoformulations need to systematically explored in future, for their new clinical role in prophylaxis of migraine attacks in children. Clinical reports have affirmed the role of cinnarizine in migraine prophylaxis. Research needs to be dedicated to develop dosage forms for efficacious bioavailability and drug directly to brain.
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109
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Krieg BJ, Taghavi SM, Amidon GL, Amidon GE. In Viv o Predictive Dissolution: Transport Analysis of the CO 2 , Bicarbonate In Vivo Buffer System. J Pharm Sci 2014; 103:3473-3490. [DOI: 10.1002/jps.24108] [Citation(s) in RCA: 63] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2014] [Revised: 06/13/2014] [Accepted: 07/14/2014] [Indexed: 11/10/2022]
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110
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Biopharmaceutical profiling of new antitumor pyrazole derivatives. Molecules 2014; 19:16381-401. [PMID: 25314601 PMCID: PMC6271227 DOI: 10.3390/molecules191016381] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2014] [Revised: 09/26/2014] [Accepted: 09/29/2014] [Indexed: 11/16/2022] Open
Abstract
Several new pyrazole derivatives have demonstrated promising antiproliferative and cytotoxic effects, but their poor solubility raised concerns over possible biopharmaceutical limitations. In order to improve their pharmaceutical potential we performed the biopharmaceutical profiling for nine pyrazole compounds using in vitro and computational methods. The experimental solubility was determined in five different media using a validated HPLC method. Although the experimental solubility was lower than the predicted one, a good linear relationship was observed. The results also indicated a minimal impact of endogenous tensioactives on solubility, suggesting dissolution rate limited absorption. The in silico experiments were focused on identification of molecular determinants of solubility, evaluation of drug-likeness, prediction of in vivo absorption based on mechanistic models, as well as identification of the main factors that could impact on the oral bioavailability. The results suggested that dose, solubility and particle size are the main determinants of absorption, whereas permeability has little effect, confirming the BCS Class II behavior of the compounds. The present investigation was able to rank the tested compounds in terms of biopharmaceutical behavior, and indicated the B3 series compounds as having a more favorable absorption profile making them the main candidates for advance to the pre-clinical in vivo studies.
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111
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Stappaerts J, Wuyts B, Tack J, Annaert P, Augustijns P. Human and simulated intestinal fluids as solvent systems to explore food effects on intestinal solubility and permeability. Eur J Pharm Sci 2014; 63:178-86. [DOI: 10.1016/j.ejps.2014.07.009] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2014] [Revised: 06/26/2014] [Accepted: 07/14/2014] [Indexed: 10/25/2022]
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112
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Morrison JS, Nophsker MJ, Haskell RJ. A Combination Turbidity and Supernatant Microplate Assay to Rank‐Order the Supersaturation Limits of Early Drug Candidates. J Pharm Sci 2014; 103:3022-32. [DOI: 10.1002/jps.24090] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2013] [Revised: 05/02/2014] [Accepted: 06/23/2014] [Indexed: 11/11/2022]
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113
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Michaudel Q, Journot G, Regueiro-Ren A, Goswami A, Guo Z, Tully TP, Zou L, Ramabhadran RO, Houk KN, Baran PS. Improving physical properties via C-H oxidation: chemical and enzymatic approaches. Angew Chem Int Ed Engl 2014; 53:12091-6. [PMID: 25244630 DOI: 10.1002/anie.201407016] [Citation(s) in RCA: 72] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2014] [Indexed: 01/04/2023]
Abstract
Physicochemical properties constitute a key factor for the success of a drug candidate. Whereas many strategies to improve the physicochemical properties of small heterocycle-type leads exist, complex hydrocarbon skeletons are more challenging to derivatize because of the absence of functional groups. A variety of C-H oxidation methods have been explored on the betulin skeleton to improve the solubility of this very bioactive, yet poorly water-soluble, natural product. Capitalizing on the innate reactivity of the molecule, as well as the few molecular handles present on the core, allowed oxidations at different positions across the pentacyclic structure. Enzymatic oxidations afforded several orthogonal oxidations to chemical methods. Solubility measurements showed an enhancement for many of the synthesized compounds.
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Affiliation(s)
- Quentin Michaudel
- Department of Chemistry, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037 (USA)
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114
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Michaudel Q, Journot G, Regueiro-Ren A, Goswami A, Guo Z, Tully TP, Zou L, Ramabhadran RO, Houk KN, Baran PS. Improving Physical Properties via CH Oxidation: Chemical and Enzymatic Approaches. Angew Chem Int Ed Engl 2014. [DOI: 10.1002/ange.201407016] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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115
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Fagerberg JH, Karlsson E, Ulander J, Hanisch G, Bergström CAS. Computational prediction of drug solubility in fasted simulated and aspirated human intestinal fluid. Pharm Res 2014; 32:578-89. [PMID: 25186438 PMCID: PMC4300419 DOI: 10.1007/s11095-014-1487-z] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2014] [Accepted: 08/15/2014] [Indexed: 11/24/2022]
Abstract
Purpose To develop predictive models of apparent solubility (Sapp) of lipophilic drugs in fasted state simulated intestinal fluid (FaSSIF) and aspirated human intestinal fluid (HIF). Methods Measured Sapp values in FaSSIF, HIF and phosphate buffer pH 6.5 (PhBpH6.5) for 86 lipophilic drugs were compiled and divided into training (Tr) and test (Te) sets. Projection to latent structure (PLS) models were developed through variable selection of calculated molecular descriptors. Experimentally determined properties were included to investigate their contribution to the predictions. Results Modest relationships between Sapp in PhBpH6.5 and FaSSIF (R2 = 0.61) or HIF (R2 = 0.62) were found. As expected, there was a stronger correlation obtained between FaSSIF and HIF (R2 = 0.78). Computational models were developed using calculated descriptors alone (FaSSIF, R2 = 0.69 and RMSEte of 0.77; HIF, R2 = 0.84 and RMSEte of 0.81). Accuracy improved when solubility in PhBpH6.5 was added as a descriptor (FaSSIF, R2 = 0.76 and RMSETe of 0.65; HIF, R2 = 0.86 and RMSETe of 0.69), whereas no improvement was seen when melting point (Tm) or logDpH 6.5 were included in the models. Conclusion Computational models were developed, that reliably predicted Sapp of lipophilic compounds in intestinal fluid, from molecular structures alone. If experimentally determined pH-dependent solubility values were available, this further improved the accuracy of the predictions.
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Affiliation(s)
- Jonas H Fagerberg
- Department of Pharmacy, Uppsala University, Biomedical Centre, P.O. Box 580, SE-751 23, Uppsala, Sweden
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116
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Real time Raman imaging to understand dissolution performance of amorphous solid dispersions. J Control Release 2014; 188:53-60. [DOI: 10.1016/j.jconrel.2014.05.061] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2014] [Revised: 05/30/2014] [Accepted: 05/30/2014] [Indexed: 11/22/2022]
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117
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Nokhodchi A, Asare-Addo K. Drug release from matrix tablets: physiological parameters and the effect of food. Expert Opin Drug Deliv 2014; 11:1401-18. [DOI: 10.1517/17425247.2014.924498] [Citation(s) in RCA: 15] [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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118
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Is the full potential of the biopharmaceutics classification system reached? Eur J Pharm Sci 2014; 57:224-31. [DOI: 10.1016/j.ejps.2013.09.010] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2013] [Revised: 09/05/2013] [Accepted: 09/15/2013] [Indexed: 11/18/2022]
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119
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Madelung P, Østergaard J, Bertelsen P, Jørgensen EV, Jacobsen J, Müllertz A. Impact of sodium dodecyl sulphate on the dissolution of poorly soluble drug into biorelevant medium from drug-surfactant discs. Int J Pharm 2014; 467:1-8. [DOI: 10.1016/j.ijpharm.2014.02.043] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2013] [Revised: 02/22/2014] [Accepted: 02/27/2014] [Indexed: 11/30/2022]
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120
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Bergström CA, Holm R, Jørgensen SA, Andersson SB, Artursson P, Beato S, Borde A, Box K, Brewster M, Dressman J, Feng KI, Halbert G, Kostewicz E, McAllister M, Muenster U, Thinnes J, Taylor R, Mullertz A. Early pharmaceutical profiling to predict oral drug absorption: Current status and unmet needs. Eur J Pharm Sci 2014; 57:173-99. [DOI: 10.1016/j.ejps.2013.10.015] [Citation(s) in RCA: 192] [Impact Index Per Article: 19.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2013] [Revised: 10/17/2013] [Accepted: 10/27/2013] [Indexed: 01/17/2023]
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121
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Larsen AT, Åkesson P, Juréus A, Saaby L, Abu-Rmaileh R, Abrahamsson B, Østergaard J, Müllertz A. Bioavailability of cinnarizine in dogs: effect of SNEDDS loading level and correlation with cinnarizine solubilization during in vitro lipolysis. Pharm Res 2013; 30:3101-13. [PMID: 23949249 DOI: 10.1007/s11095-013-1145-x] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2013] [Accepted: 07/01/2013] [Indexed: 01/13/2023]
Abstract
PURPOSE To investigate the effect of increasing the loading level of the poorly soluble drug cinnarizine in a self-nanoemulsifying drug delivery system (SNEDDS) both in vitro and in vivo. METHODS A fixed dose of cinnarizine was administered orally to dogs in solution in different amounts of SNEDDS vehicle. Furthermore, the SNEDDSs were characterised using the dynamic in vitro lipolysis model. RESULTS Statistical differences in bioavailability were not obtained between the different amounts of SNEDDS vehicle, in spite of differences in the tendency of cinnarizine to precipitate during in vitro lipolysis of the treatments. Use of the SNEDDS concept decreased the variation in cinnarizine exposure observed between dogs as compared to administering cinnarizine in an aqueous suspension. CONCLUSIONS Optimization of SNEDDSs towards keeping the drug compound in solution upon in vitro lipolysis of the SNEDDSs may not be as important as previously suggested.
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Affiliation(s)
- Anne T Larsen
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, 2100, Copenhagen, Denmark
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122
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Wuyts B, Brouwers J, Mols R, Tack J, Annaert P, Augustijns P. Solubility profiling of HIV protease inhibitors in human intestinal fluids. J Pharm Sci 2013; 102:3800-7. [PMID: 23939880 DOI: 10.1002/jps.23698] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2013] [Revised: 07/17/2013] [Accepted: 07/22/2013] [Indexed: 01/13/2023]
Abstract
The present study pursued to profile the intestinal solubility of nine HIV protease inhibitors (PIs) in fasted- and fed-state human intestinal fluids (FaHIF, FeHIF) aspirated from four volunteers. In addition, the ability of fasted- and fed-state simulated intestinal fluids (FaSSIF, FeSSIF) to predict the intestinal solubility was evaluated. All PIs were poorly soluble in FaHIF (from 7 μM for ritonavir to 327 μM for darunavir) and FeHIF (from 15 μM for atazanavir to 409μM for darunavir). For four of nine PIs, food intake significantly enhanced the solubilizing capacity of intestinal fluids (up to 18.4-fold increase for ritonavir). The intersubject variability (average coefficient of variance CVfed = 60.6%, CVfasted = 40.4%) was higher as compared with the intrasubject variability (CVfed = 41.3%, CVfasted = 20.5%). PI solubilities correlated reasonably well between FaSSIF and FaHIF (R = 0.817), but not between FeSSIF and FeHIF (R = 0.617). To conclude, postprandial conditions increased the inter- and intrasubject variability of the PIs. The inability of FeSSIF to accurately predict the FeHIF solubility emphasizes the need for a multivariate approach to determine solubility profiles, taking into account solid-state characteristics, pH, mixed bile acid/phospholipid micelles, and digestive products.
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Affiliation(s)
- Benjamin Wuyts
- Drug Delivery and Disposition, Department of Pharmaceutical and Pharmacological Sciences, KU Leuven, Belgium
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123
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Takács-Novák K, Szőke V, Völgyi G, Horváth P, Ambrus R, Szabó-Révész P. Biorelevant solubility of poorly soluble drugs: rivaroxaban, furosemide, papaverine and niflumic acid. J Pharm Biomed Anal 2013; 83:279-85. [PMID: 23770783 DOI: 10.1016/j.jpba.2013.05.011] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2013] [Revised: 05/09/2013] [Accepted: 05/10/2013] [Indexed: 11/25/2022]
Abstract
In this work the biorelevant solubility of four drugs representing different acid-base property, wide range of lipohilicity and low aqueous solubility was studied. The equilibrium solubility of rivaroxaban (non-ionizable), furosemide (acid), papaverine (base) and niflumic acid (ampholyte) was determined in simulated gastric fluid (SGF pH 1.2), in simulated intestinal fluid fasted state (FaSSIF pH 6.5) and fed state (FeSSIF pH 5.0) and their corresponding blank buffers at a temperature of 37 °C using saturation shake-flask method. The concentration was measured by optimized HPLC analysis. The solubilizing effect of bile acid/lipid micelles as additive components of biorelevent media (BRM) is expressed with the solubility ratio (SR: SBRM/Sblank buffer) and the food effect was estimated from SFeSSIF/SFaSSIF coefficient. It was revealed that ionization plays primarily role in solubility of compounds which undergo ionization in BRM. The solubilizing effect in FaSSIF was marginal for the neutral compound (rivaroxaban) and for molecules are anionic at pH 6.5 (furosemide and niflumic acid). The higher concentration of solubilizing agents in FeSSIF improved the solubility of papaverine carrying positive charge and niflumic acid being partially zwitterionic at pH 5.0.
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Affiliation(s)
- Krisztina Takács-Novák
- Department of Pharmaceutical Chemistry, Semmelweis University, H-1092 Hőgyes Endre street 9, Budapest, Hungary.
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124
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Mateus A, Matsson P, Artursson P. Rapid Measurement of Intracellular Unbound Drug Concentrations. Mol Pharm 2013; 10:2467-78. [DOI: 10.1021/mp4000822] [Citation(s) in RCA: 119] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Affiliation(s)
- André Mateus
- Department of Pharmacy, Uppsala University, Box 580, SE-751 23 Uppsala, Sweden
- Research Institute for Medicines
and Pharmaceutical Sciences (iMed.UL), Faculty of Pharmacy, University
of Lisbon, 1649-003 Lisbon, Portugal
| | - Pär Matsson
- Department of Pharmacy, Uppsala University, Box 580, SE-751 23 Uppsala, Sweden
- Uppsala University Drug Optimization
and Pharmaceutical Profiling Platform (UDOPP)—a node of the
Chemical Biology Consortium Sweden (CBCS), Department of Pharmacy, Uppsala University, 751 23 Uppsala, Sweden
| | - Per Artursson
- Department of Pharmacy, Uppsala University, Box 580, SE-751 23 Uppsala, Sweden
- Uppsala University Drug Optimization
and Pharmaceutical Profiling Platform (UDOPP)—a node of the
Chemical Biology Consortium Sweden (CBCS), Department of Pharmacy, Uppsala University, 751 23 Uppsala, Sweden
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125
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Tehler U, Fagerberg JH, Svensson R, Larhed M, Artursson P, Bergström CAS. Optimizing Solubility and Permeability of a Biopharmaceutics Classification System (BCS) Class 4 Antibiotic Drug Using Lipophilic Fragments Disturbing the Crystal Lattice. J Med Chem 2013; 56:2690-4. [DOI: 10.1021/jm301721e] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Ulrika Tehler
- Uppsala University Drug Optimization
and Pharmaceutical Profiling Platform, Department of Pharmacy, Uppsala
Biomedical Center, Uppsala University,
P.O. Box 580, SE-751 23 Uppsala, Sweden
| | - Jonas H. Fagerberg
- Uppsala University Drug Optimization
and Pharmaceutical Profiling Platform, Department of Pharmacy, Uppsala
Biomedical Center, Uppsala University,
P.O. Box 580, SE-751 23 Uppsala, Sweden
| | - Richard Svensson
- Uppsala University Drug Optimization
and Pharmaceutical Profiling Platform, Department of Pharmacy, Uppsala
Biomedical Center, Uppsala University,
P.O. Box 580, SE-751 23 Uppsala, Sweden
| | - Mats Larhed
- Organic Pharmaceutical Chemistry,
Department of Medicinal Chemistry, Uppsala Biomedical Center, Uppsala University, P.O. Box 574, SE-751 23 Uppsala,
Sweden
| | - Per Artursson
- Uppsala University Drug Optimization
and Pharmaceutical Profiling Platform, Department of Pharmacy, Uppsala
Biomedical Center, Uppsala University,
P.O. Box 580, SE-751 23 Uppsala, Sweden
| | - Christel A. S. Bergström
- Uppsala University Drug Optimization
and Pharmaceutical Profiling Platform, Department of Pharmacy, Uppsala
Biomedical Center, Uppsala University,
P.O. Box 580, SE-751 23 Uppsala, Sweden
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126
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SNEDDS Containing Poorly Water Soluble Cinnarizine; Development and in Vitro Characterization of Dispersion, Digestion and Solubilization. Pharmaceutics 2012; 4:641-65. [PMID: 24300374 PMCID: PMC3834928 DOI: 10.3390/pharmaceutics4040641] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2012] [Revised: 11/30/2012] [Accepted: 12/03/2012] [Indexed: 11/16/2022] Open
Abstract
Self-Nanoemulsifying Drug Delivery Systems (SNEDDSs) were developed using well-defined excipients with the objective of mimicking digested SNEDDSs without the use of enzymes and in vitro lipolysis models and thereby enabling studies of the morphology and size of nanoemulsions as well as digested nanoemulsions by Cryo-TEM imaging and Dynamic Light Scattering. Four SNEDDSs (I-IV) were developed. Going from SNEDDS I to IV lipid content and solubility of the model drug cinnarizine decreased, which was also the case for dispersion time and droplet size. Droplet size of all SNEDDS was evaluated at 1% (w/w) dispersion under different conditions. Cinnarizine incorporation increased the droplet size of SNEDDSs I and II whereas for SNEDDSs III and IV no difference was observed. At low pH cinnarizine had no effect on droplet size, probably due to increased aqueous solubility and partitioning into the aqueous phase. Dispersion of the SNEDDSs in Simulated Intestinal Media (SIM) containing bile salts and phospholipids resulted in a decrease in droplet size for all SNEDDS, as compared to dispersion in buffer. Increasing the bile salt/phospholipid content in the SIM decreased the droplet sizes further. Mimicked digested SNEDDS with highest lipid content (I and II) formed smaller nanoemulsion droplet sizes upon dispersion in SIM, whereas droplet size from III and IV were virtually unchanged by digestion. Increasing the bile acid/phosphatidylcholine content in the SIM generally decreased droplet size, due to the solubilizing power of the endogenous surfactants. Digestion of SNEDDSs II resulted in formation of vesicles or micelles in fasted and fed state SIM, respectively. The developed and characterized SNEDDS provide for a better knowledge of the colloid phases generated during digestion of SNEDDS and therefore will enable studies that may yield a more detailed understanding of SNEDDS performance.
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127
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Juhnke M, John E. Wet-Media Milling of Colloidal Drug Suspensions Stabilized by Means of Charged Nanoparticles. Chem Eng Technol 2012. [DOI: 10.1002/ceat.201200139] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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128
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Fagerberg JH, Al-Tikriti Y, Ragnarsson G, Bergström CA. Ethanol Effects on Apparent Solubility of Poorly Soluble Drugs in Simulated Intestinal Fluid. Mol Pharm 2012; 9:1942-52. [DOI: 10.1021/mp2006467] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Jonas H. Fagerberg
- Uppsala University
Drug Optimization
and Pharmaceutical Profiling Platform, Department of Pharmacy, Uppsala
University, Uppsala Biomedical Center, P.O. Box 580, SE-751 23 Uppsala,
Sweden
| | - Yassir Al-Tikriti
- Uppsala University
Drug Optimization
and Pharmaceutical Profiling Platform, Department of Pharmacy, Uppsala
University, Uppsala Biomedical Center, P.O. Box 580, SE-751 23 Uppsala,
Sweden
| | - Gert Ragnarsson
- Medical Products
Agency, P.O.
Box 26, SE-751 03, Uppsala, Sweden
| | - Christel A.S. Bergström
- Uppsala University
Drug Optimization
and Pharmaceutical Profiling Platform, Department of Pharmacy, Uppsala
University, Uppsala Biomedical Center, P.O. Box 580, SE-751 23 Uppsala,
Sweden
- Drug Delivery, Disposition and
Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University,
381 Royal Parade, Parkville, Victoria 3052, Australia
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129
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Paixão P, Gouveia LF, Morais JA. Prediction of the human oral bioavailability by using in vitro and in silico drug related parameters in a physiologically based absorption model. Int J Pharm 2012; 429:84-98. [DOI: 10.1016/j.ijpharm.2012.03.019] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2012] [Revised: 03/08/2012] [Accepted: 03/09/2012] [Indexed: 12/13/2022]
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130
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Dickschen K, Willmann S, Thelen K, Lippert J, Hempel G, Eissing T. Physiologically Based Pharmacokinetic Modeling of Tamoxifen and its Metabolites in Women of Different CYP2D6 Phenotypes Provides New Insight into the Tamoxifen Mass Balance. Front Pharmacol 2012; 3:92. [PMID: 22661948 PMCID: PMC3357105 DOI: 10.3389/fphar.2012.00092] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2012] [Accepted: 04/27/2012] [Indexed: 12/15/2022] Open
Abstract
Tamoxifen is a first-line endocrine agent in the mechanism-based treatment of estrogen receptor positive (ER+) mammary carcinoma and applied to breast cancer patients all over the world. Endoxifen is a secondary and highly active metabolite of tamoxifen that is formed among others by the polymorphic cytochrome P450 2D6 (CYP2D6). It is widely accepted that CYP2D6 poor metabolizers exert a pronounced decrease in endoxifen steady-state plasma concentrations compared to CYP2D6 extensive metabolizers. Nevertheless, an in-depth understanding of the chain of cause and effect between CYP2D6 genotype, endoxifen steady-state plasma concentration, and subsequent tamoxifen treatment benefit still remains to be evolved. In this study, physiologically based pharmacokinetic (PBPK)-modeling was applied to mechanistically investigate the impact of CYP2D6 phenotype on endoxifen formation in female breast cancer patients undergoing tamoxifen therapy. A PBPK-model of tamoxifen and its pharmacologically important metabolites N-desmethyltamoxifen (NDM-TAM), 4-hydroxytamoxifen (4-OH-TAM), and endoxifen was developed and validated. This model is able to simulate the pharmacokinetics (PK) after single and repeated oral tamoxifen doses in female breast cancer patients in dependence of the CYP2D6 phenotype. A detailed model-based analysis of the mass balance offered support for a recent hypothesis stating a more prominent role for endoxifen formation from 4-OH-TAM. In the future this model provides a good basis to further investigate the linkage of PK, mode of action, and treatment outcome in dependence of factors such as phenotype, ethnicity, or co-treatment with CYP2D6 inhibitors.
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Affiliation(s)
- Kristin Dickschen
- Klinische Pharmazie, Institut für Pharmazeutische und Medizinische Chemie, Westfälische Wilhelms-Universität Münster Münster, Germany
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131
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Solution Behavior of PVP-VA and HPMC-AS-Based Amorphous Solid Dispersions and Their Bioavailability Implications. Pharm Res 2012; 29:2765-76. [DOI: 10.1007/s11095-012-0695-7] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2011] [Accepted: 01/24/2012] [Indexed: 10/14/2022]
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132
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Buckley ST, Fischer SM, Fricker G, Brandl M. In vitro models to evaluate the permeability of poorly soluble drug entities: Challenges and perspectives. Eur J Pharm Sci 2012; 45:235-50. [DOI: 10.1016/j.ejps.2011.12.007] [Citation(s) in RCA: 96] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2011] [Revised: 11/26/2011] [Accepted: 12/02/2011] [Indexed: 11/16/2022]
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133
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Vithlani S, Sarraf S, Chaw CS. Formulation and in vitro evaluation of self-emulsifying formulations of Cinnarizine. Drug Dev Ind Pharm 2011; 38:1188-94. [PMID: 22196372 DOI: 10.3109/03639045.2011.643895] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
The main objectives of this study were to improve the aqueous solubility and to modify in vitro dissolution profile of hydrophobic drug using self-emulsifying drug delivery systems (SEDDS). SEDDS were formulated using Capmul PG-12, Cremophor RH 40 and Tween 20 at different weight ratios and incorporated with Cinnarizine. The drug incorporation into pre-concentrate and drug solubility in phosphate buffer (pH 7.2) were investigated. In addition, the mean droplet size and drug release profile of the SEDDS were also determined. The drug incorporation was over 120 mg per 0.5 g pre-concentrate regardless of the composition of the formulations. The solubility of Cinnarizine in phosphate buffer (pH 7.2) was at least 1500 μM in the SEDDS. Formulations with only 10% w/w Capmul PG-12 were less than 20 nm in mean diameter while those produced with at least 20% w/w Capmul PG-12 were more than 100 nm regardless of the ratios of Cremophor RH 40 to Tween 20. SEDDS showed a significant increase of the mean percentage drug release than pure drug (p < 0.0001). In general, the SEDDS with 30% w/w of Capmul PG-12 provided the greatest enhancement in drug solubility in phosphate buffer as well as rapid drug release despite forming larger droplets upon emulsification. The combination of Capmul PG-12, Tween 20 and Cremophor RH 40 can produce SEDDS which can be used as an alternative dosage form for poorly water soluble drug.
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Affiliation(s)
- Shyam Vithlani
- Department of Pharmacy, Health and Well Being, University of Sunderland, Sunderland, UK
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134
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Fancher RM, Zhang H, Sleczka B, Derbin G, Rockar R, Marathe P. Development of a Canine Model to Enable the Preclinical Assessment of Ph-dependent Absorption of Test Compounds. J Pharm Sci 2011; 100:2979-88. [DOI: 10.1002/jps.22486] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2010] [Revised: 11/12/2010] [Accepted: 12/21/2010] [Indexed: 11/10/2022]
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135
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Sun N, Avdeef A. Biorelevant pK(a) (37 °C) predicted from the 2D structure of the molecule and its pK(a) at 25 °C. J Pharm Biomed Anal 2011; 56:173-82. [PMID: 21652160 DOI: 10.1016/j.jpba.2011.05.007] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2011] [Revised: 05/09/2011] [Accepted: 05/10/2011] [Indexed: 11/25/2022]
Abstract
Values of the ionization constants at 37 °C, which are scarcely reported, are more meaningful for interpreting mechanisms of cellular transport by ionizable molecules and in mechanistic dissolution studies, which are often performed at the biorelevant temperature. An equation was developed where the pK(a) values of drug-like molecules determined at 25 °C can be simply converted to values at 37 °C, without additional measurement. The differences between the values, ΔpK(a)=pK(a)³⁷-pK(a)²⁵, were linearly fitted to a function of pK(a)²⁵ and the standard entropy of ionization, ΔS°, where the latter term was approximated by the five Abraham linear free energy solvation descriptors using multiple linear regression. The Abraham descriptors (H-bond donor and acceptor strengths, dipolar solute-solvent interactions potential, the pi- and n-electrons dispersion force, and molar volume) were determined from the 2-dimensional structure of the molecules. A total of 143 mostly drug-like molecules (207 pK(a) values at 25 °C and at 37 °C) were chosen for the study. The pK(a) values of many were determined here for the first time. Included were 34 weak acids, 85 weak bases, and 24 amphoteric compounds (6 ordinary ampholytes, 18 zwitterions).
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Affiliation(s)
- Na Sun
- pION INC, 5 Constitution Way, Woburn, MA 01801, USA.
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136
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Zhang Z, Huang Y, Gao F, Bu H, Gu W, Li Y. Daidzein-phospholipid complex loaded lipid nanocarriers improved oral absorption: in vitro characteristics and in vivo behavior in rats. NANOSCALE 2011; 3:1780-7. [PMID: 21350765 DOI: 10.1039/c0nr00879f] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
A nano-based delivery system was developed to improve the oral absorption of daidzein, which has poor hydrophilicity and lipophilicity. A daidzein-phospholipid complex (DPC) was firstly prepared to improve its lipophilicity, and then encapsulated into lipid nanocarriers (DLNs) to verify the effectiveness of the strategy in enhancing the oral delivery of daidzein. DLNs were spherical nanosized particles with evidently increased dissolution. DLNs were mainly distributed in stomach and proximal intestine of mice after oral administration, and the intestinal permeability of DLNs in rats was significantly improved when compared with that of daidzein solution. The peak concentration of daidzein in rats after oral administration of DPC and DLNs was 6833 ± 1112 ng mL(-1) and 14,512 ± 2390 ng mL(-1), respectively, which was improved over 10-fold and 21-fold than that of free daidzein. Moreover, the areas under the concentration-time curve (AUC(0-t)) of DPC and DLNs were enhanced by 3.62-fold and 6.87-fold compared with that of free daidzein. These results suggested that DLNs could be an effective strategy to improve the oral absorption of poor hydrophilic and lipophilic drugs like daidzein.
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Affiliation(s)
- Zhiwen Zhang
- Center of Pharmaceutics, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 501 Haike Road, Shanghai, 201203, China
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137
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A new in situ brain perfusion flow correction method for lipophilic drugs based on the pH-dependent Crone-Renkin equation. Pharm Res 2010; 28:517-30. [PMID: 21042838 DOI: 10.1007/s11095-010-0298-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2010] [Accepted: 09/28/2010] [Indexed: 09/29/2022]
Abstract
PURPOSE To determine the flow-corrected luminal permeability, P(c), of lipophilic drugs measured by the in situ brain perfusion method under circumstances where the traditional Crone-Renkin equation (CRE) method, using diazepam as a flow marker, often fails. METHODS The pH-dependent rate of brain penetration of five lipophilic drugs (amitriptyline, atomoxetine, imipramine, indomethacin, maprotiline, sertraline), as well as of atenolol and antipyrine, were measured in Sprague-Dawley rats. A new pH-dependent CRE was derived and applied to remove the hydrodynamic component of effective permeability, P(e), to produce P(c) values. RESULTS It was shown by the analysis of the in situ data in the pH 6.5-8.5 interval for the lipophilic bases that the average vascular flow F(pf) = 0.036 mL∙g(-1)∙s(-1), centered in a "flow-limit window" (FLW) bounded by P (e) (min) = 170 and P (e) (max) = 776 (10(-6) cm∙s(-1) units). It was shown that the traditional CRE is expected not to work for half of the molecules in the FLW and is expected to underestimate (up to 64-fold) the other half of the molecules. CONCLUSION The new pH-CRE flow correction method applied to lipophilic ionizable drugs, based on the pH partition hypothesis, can overcome the limitations of the traditional CRE.
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