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Bei H, Zhao P, Shen L, Yang Q, Yang Y. Assembled pH-Responsive Gastric Drug Delivery Systems Based on 3D-Printed Shells. Pharmaceutics 2024; 16:717. [PMID: 38931841 PMCID: PMC11206575 DOI: 10.3390/pharmaceutics16060717] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2024] [Revised: 05/21/2024] [Accepted: 05/22/2024] [Indexed: 06/28/2024] Open
Abstract
Gastric acid secretion is closely associated with the development and treatment of chronic gastritis, gastric ulcers, and reflux esophagitis. However, gastric acid secretion is affected by complex physiological and pathological factors, and real-time detection and control are complicated and expensive. A gastric delivery system for antacids and therapeutics in response to low pH in the stomach holds promise for smart and personalized treatment of stomach diseases. In this study, pH-responsive modular units were used to assemble various modular devices for self-regulation of pH and drug delivery to the stomach. The modular unit with a release window of 50 mm2 could respond to pH and self-regulate within 10 min, which is related to its downward floatation and internal gas production. The assembled devices could stably float downward in the medium and detach sequentially at specific times. The assembled devices loaded with antacids exhibited smart pH self-regulation under complex physiological and pathological conditions. In addition, the assembled devices loaded with antacids and acid suppressors could multi-pulse or prolong drug release after rapid neutralization of gastric acid. Compared with traditional coating technology, 3D printing can print the shell layer by layer, flexibly adjust the internal and external structure and composition, and assemble it into a multi-level drug release system. Compared with traditional coating, 3D-printed shells have the advantage of the flexible adjustment of internal and external structure and composition, and are easy to assemble into a complex drug delivery system. This provides a universal and flexible strategy for the personalized treatment of diseases with abnormal gastric acid secretion, especially for delivering acid-unstable drugs.
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Affiliation(s)
| | | | | | | | - Yan Yang
- College of Pharmaceutical Science, Zhejiang University of Technology, Hangzhou 310014, China; (H.B.); (P.Z.); (L.S.); (Q.Y.)
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Kir F, Al-Sulaiti FK, Sahin S. Evaluation of in vitro dissolution profiles of modified-release metoprolol succinate tablets crushed using mortar and pestle technique. Eur J Pharm Sci 2024; 194:106694. [PMID: 38191064 DOI: 10.1016/j.ejps.2024.106694] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2023] [Revised: 12/24/2023] [Accepted: 01/04/2024] [Indexed: 01/10/2024]
Abstract
PURPOSE Clinical practice guidelines advise against crushing modified-release dosage forms. Metoprolol succinate modified-release (MS-MR) tablets are commonly crushed in clinical practice to facilitate administration to patients with swallowing difficulties or using feeding tubes. To date, the effect of this practice remains unexplored. The in vitro effects of crushing commercially available MS-MR tablets were explored using a holistic approach. METHODS Dissolution profiles of crushed versus whole MS-MR tablets were compared. Tablets were crushed to powder state using pragmatic method mimicking hospital practices. For standardization purposes, the same operator, duration (60 seconds), hand, and mortar-pestle apparatus were used. Dissolution studies were conducted per U.S. Pharmacopeia at pH 1.2, pH 4.5, and pH 6.8 with USP apparatus 2 (paddle) at rotation speed of 50 rpm at 37±0.5 °C in 500 mL dissolution media. Samples were withdrawn at predetermined time points. Percent drug dissolved was measured by validated UV-vis Spectrophotometry. Comprehensive analysis of the dissolution data was conducted using model-independent, model-dependent, and ANOVA-based approaches (SPSS v.23 at α=0.05). Similarity (f2) and difference (f1) factors were calculated to compare the dissolution profiles between crushed (CT) and whole tablets (WT). Goodness of fit (GOF) analysis examined the compliance between in vitro dissolution behaviors and several drug release models. Model selection was based on GOF plots, Akaike criteria and adjusted coefficient of determination (R2adj). Imaging and particle size distribution analysis were conducted to examine associated surface and morphologic changes. RESULTS The dissolution profiles were not similar at pH 4.5 (f2=45.43, f1=18.97) and pH 6.8 (f2=31.47, f1=32.94). CT best fitted with Higuchi (pH 1.2: R2adj=0.9990), Weibull (pH 4.5: R2adj=0.9884), and Korsmeyer-Peppas (pH 6.8: R2adj=0.9719). Contrastingly, WT best fitted with Hopfenberg (pH 1.2: R2adj=0.9986), logistic (pH 4.5: R2adj=0.9839) and first-order (pH 6.8: R2adj=0.9979) models. A significant difference in the dissolution profiles was found between CT and WT using multivariate analysis of variance per time points and between the tablet forms (p=0.004). This was confirmed by unparalleled dissolution profiles. Crushing resulted in variations in particle size and surface morphological changes to the micropellets. CONCLUSION Crushing practices change the dissolution profile of MS-MR tablets by deforming the surface morphology of embedded micropellets. Amounts of drug dissolved between CT and WT were not the same at the compared time points across gastrointestinal pH ranges. This suggests potential clinical impact on plasma-concentration profiles of critically ill patients using feeding tube.
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Affiliation(s)
- Fatma Kir
- Department of Pharmaceutical Technology, Faculty of Pharmacy, Hacettepe University, Ankara, Turkey
| | - Fatima K Al-Sulaiti
- Department of Pharmaceutical Technology, Faculty of Pharmacy, Hacettepe University, Ankara, Turkey
| | - Selma Sahin
- Department of Pharmaceutical Technology, Faculty of Pharmacy, Hacettepe University, Ankara, Turkey.
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Bapat P, Paul S, Thakral NK, Tseng YC, Taylor LS. Does Media Choice Matter When Evaluating the Performance of Hydroxypropyl Methylcellulose Acetate Succinate-Based Amorphous Solid Dispersions? Mol Pharm 2023; 20:5714-5727. [PMID: 37751517 DOI: 10.1021/acs.molpharmaceut.3c00586] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/28/2023]
Abstract
Hydroxypropyl methylcellulose acetate succinate (HPMCAS) is a weakly acidic polymer that is widely used in the formulation of amorphous solid dispersions (ASDs). While the pH-dependent solubility of HPMCAS is widely recognized, the role of other solution properties, including buffer capacity, is less well understood in the context of ASD dissolution. The goal of this study was to elucidate the rate-limiting steps for drug and HPMCAS release from ASDs formulated with two poorly water soluble model drugs, indomethacin and indomethacin methyl ester. The surface area normalized release rate of the drug and/or polymer in a variety of media was determined. The HPMCAS gel layer apparent pH was determined by incorporating pH sensitive dyes into the polymer matrix. Water uptake extent and rate into the ASDs were measured gravimetrically. For neat HPMCAS, the rate-limiting step for polymer dissolution was observed to be the polymer solubility at the polymer-solution interface. This, in turn, was impacted by the gel layer pH which was found to be substantially lower than the bulk solution pH, varying with medium buffer capacity. For the ASDs, the HPMCAS release rate was found to control the drug release rate. However, both drugs reduced the polymer release rate with indomethacin methyl ester having a larger impact. In low buffer capacity media, the presence of the drug had less impact on release rates when compared to observations in higher strength buffers, suggesting changes in the rate-limiting steps for HPMCAS dissolution. The observations made in this study can contribute to the fundamental understanding of acidic polymer dissolution in the presence and absence of a molecularly dispersed lipophilic drug and will help aid in the design of more in vivo relevant release testing experiments.
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Affiliation(s)
- Pradnya Bapat
- Department of Industrial and Physical Pharmacy, College of Pharmacy, Purdue University, West Lafayette, Indiana 47907, United States
| | - Shubhajit Paul
- Material and Analytical Sciences, Research and Development, Boehringer Ingelheim Pharmaceuticals, Inc., Ridgefield, Connecticut 06877, United States
| | - Naveen K Thakral
- Material and Analytical Sciences, Research and Development, Boehringer Ingelheim Pharmaceuticals, Inc., Ridgefield, Connecticut 06877, United States
| | - Yin-Chao Tseng
- Material and Analytical Sciences, Research and Development, Boehringer Ingelheim Pharmaceuticals, Inc., Ridgefield, Connecticut 06877, United States
| | - Lynne S Taylor
- Department of Industrial and Physical Pharmacy, College of Pharmacy, Purdue University, West Lafayette, Indiana 47907, United States
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Niederquell A, Stoyanov E, Kuentz M. Physiological Buffer Effects in Drug Supersaturation - A Mechanistic Study of Hydroxypropyl Cellulose as Precipitation Inhibitor. J Pharm Sci 2023; 112:1897-1907. [PMID: 36813134 DOI: 10.1016/j.xphs.2023.02.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Revised: 02/14/2023] [Accepted: 02/14/2023] [Indexed: 02/22/2023]
Abstract
Phosphate buffer is predominantly used instead of the more physiological bicarbonate buffer, as the latter requires a technical solution of adequate gas mixing. Recent pioneering work on how bicarbonate buffer affected drug supersaturation revealed interesting effects that call for more mechanistic understanding. Therefore, this study used hydroxypropyl cellulose as a model precipitation inhibitor and real-time desupersaturation testing was conducted with the drugs bifonazole, ezetimibe, tolfenamic acid and triclabendazole. Specific buffer effects for the different compounds were noted and overall, statistical significance was found for the precipitation induction time (p = 0.0088). Interestingly, molecular dynamics simulation revealed a conformational effect of the polymer in the presence of the different buffer types. Subsequent molecular docking trials suggested a stronger interaction energy of drug and polymer in the presence of phosphate compared to bicarbonate buffer (p =0.0010). In conclusion, a better mechanistic understanding of how different buffers affect drug-polymer interactions regarding drug supersaturation was achieved. Further mechanisms may account for the overall buffer effects and additional research on drug supersaturation is certainly needed, but it can already be concluded that bicarbonate buffering should be used more often for in vitro testing in drug development.
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Affiliation(s)
- Andreas Niederquell
- School of Life Sciences, University of Applied Sciences and Arts Northwestern Switzerland, CH 4132 Muttenz, Switzerland
| | - Edmont Stoyanov
- Nisso Chemical Europe, Berliner Allee 42, 40212, Düsseldorf, Germany
| | - Martin Kuentz
- School of Life Sciences, University of Applied Sciences and Arts Northwestern Switzerland, CH 4132 Muttenz, Switzerland.
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O’Farrell C, Simmons MJH, Batchelor HK, Stamatopoulos K. The Effect of Biorelevant Hydrodynamic Conditions on Drug Dissolution from Extended-Release Tablets in the Dynamic Colon Model. Pharmaceutics 2022; 14:pharmaceutics14102193. [PMID: 36297627 PMCID: PMC9609852 DOI: 10.3390/pharmaceutics14102193] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2022] [Revised: 10/06/2022] [Accepted: 10/11/2022] [Indexed: 11/06/2022] Open
Abstract
The in vitro release of theophylline from an extended-release dosage form was studied under different hydrodynamic conditions in a United States Pharmacopoeial (USP) dissolution system II and a bespoke in vitro tubular model of the human colon, the Dynamic Colon Model (DCM). Five biorelevant motility patterns extracted from in vivo data were applied to the DCM, mimicking the human proximal colon under baseline conditions and following stimulation using polyethylene glycol or maltose; these represent the lower and upper bounds of motility normally expected in vivo. In the USPII, tablet dissolution was affected by changing hydrodynamic conditions at different agitation speeds of 25, 50 and 100 rpm. Applying different motility patterns in the DCM affected the dissolution profiles produced, with theophylline release at 24 h ranging from 56.74 ± 2.00% (baseline) to 96.74 ± 9.63% (maltose-stimulated). The concentration profiles of theophylline were markedly localized when measured at different segments of the DCM tube, highlighting the importance of a segmented lumen in intestine models and in generating spatial information to support simple temporal dissolution profiles. The results suggested that the shear stresses invoked by the unstimulated, healthy adult human colon may be lower than those in the USPII at 25 rpm and thus insufficient to achieve total release of a therapeutic compound from a hydroxyethyl cellulose matrix. When operated under stimulated conditions, drug release in the DCM was between that achieved at 25 and 50 rpm in the USPII.
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Affiliation(s)
- Connor O’Farrell
- School of Chemical Engineering, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
- Correspondence:
| | - Mark J. H. Simmons
- School of Chemical Engineering, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
| | - Hannah K. Batchelor
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, 161 Cathedral Street, Glasgow G4 0RE, UK
| | - Konstantinos Stamatopoulos
- School of Chemical Engineering, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
- Biopharmaceutics, DPD, MDS, GSK, David Jack Centre, Park Road, Ware, Hertfordshire SG12 0DP, UK
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Varum F, Thorne H, Bravo R, Gilgen D, Hartig C, Nicolas G, Wild D, Liakoni E, Haschke M. Targeted colonic release formulations of mesalazine – A clinical pharmaco-scintigraphic proof-of-concept study in healthy subjects and patients with mildly active ulcerative colitis. Int J Pharm 2022; 625:122055. [DOI: 10.1016/j.ijpharm.2022.122055] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2022] [Revised: 07/22/2022] [Accepted: 07/23/2022] [Indexed: 01/13/2023]
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Haznar-Garbacz D, Hoc D, Garbacz G, Lachman M, Słomińska D, Romański M. Dissolution of a Biopharmaceutics Classification System Class II Free Acid from Immediate Release Tablets Containing a Microenvironmental pH Modulator: Comparison of a Biorelevant Bicarbonate Buffering System with Phosphate Buffers. AAPS PharmSciTech 2022; 23:203. [PMID: 35882674 DOI: 10.1208/s12249-022-02310-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2022] [Accepted: 05/17/2022] [Indexed: 11/30/2022] Open
Abstract
Poor water dissolution of active pharmaceutical ingredients (API) limits the rate of absorption from the gastrointestinal tract. Increasing the pH of a solid form microenvironment can enhance the dissolution of weakly acidic drugs, but data on this phenomenon in a physiologically relevant bicarbonate media are lacking. In this paper, we examined the effect of a microenvironmental pH modulator (Na2HPO4) on the dissolution of a Biopharmaceutics Classification System (BCS) class II free weak acid (ibuprofen) at biorelevant conditions, including an automatic bicarbonate buffering system, as well as in compendial (50 mM) and low-concentration (10 mM) phosphate buffers with no external pH control. The tablets of 200 mg ibuprofen with either Na2HPO4 (phosphate formulation, PF) or NaCl (reference formulation, RF) were manufactured using a compression method. In a pH 2 simulated gastric fluid, only PF produced a transient supersaturation of ibuprofen, dissolving a fourfold higher drug amount than RF. In a bicarbonate-buffered simulated intestinal fluid with a dynamically controlled pH (5.7, 7.2, and 5.8 to 7.7 gradient), PF dissolved more drug within 30 min than RF (p ≤ 0.019). Of note, the use of a 50 mM phosphate buffer pH 7.2 provided opposite results-RF dissolved the API much faster than PF. Moreover, 10 mM phosphate buffers of pH 5.6 and 7.2 could neither maintain a constant pH nor mimic the bicarbonate buffer performance. In conclusion, the use of a bicarbonate-buffered intestinal fluid, instead of phosphate buffers, may be essential in dissolution tests of BCS class II drugs combined with pH modulators.
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Affiliation(s)
- Dorota Haznar-Garbacz
- Department of Drug Form Technology, Wroclaw Medical University, 211a Borowska St., 50-556, Wrocław, Poland
| | - Dagmara Hoc
- Physiolution Polska, 74 Piłsudskiego St., 50-020, Wrocław, Poland
| | - Grzegorz Garbacz
- Physiolution GmbH, 49a Walther-Rathenau-Straße, 17489, Greifswald, Germany
| | - Marek Lachman
- Budenheim KG, 27 Rheinstraße, 55257, Budenheim, Germany
| | - Daria Słomińska
- Department of Pharmacology, Poznan University of Medical Sciences, 3 Rokietnicka St., 60-806, Poznań, Poland
| | - Michał Romański
- Department of Physical Pharmacy and Pharmacokinetics, Poznan University of Medical Sciences, 3 Rokietnicka St., 60-806, Poznań, Poland.
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García MA, Varum F, Al-Gousous J, Hofmann M, Page S, Langguth P. In Vitro Methodologies for Evaluating Colon-Targeted Pharmaceutical Products and Industry Perspectives for Their Applications. Pharmaceutics 2022; 14:pharmaceutics14020291. [PMID: 35214024 PMCID: PMC8876830 DOI: 10.3390/pharmaceutics14020291] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Revised: 01/22/2022] [Accepted: 01/24/2022] [Indexed: 02/04/2023] Open
Abstract
Several locally acting colon-targeted products to treat colonic diseases have been recently developed and marketed, taking advantage of gastrointestinal physiology to target delivery. Main mechanisms involve pH-dependent, time-controlled and/or enzymatic-triggered release. With site of action located before systemic circulation and troublesome colonic sampling, there is room for the introduction of meaningful in vitro methods for development, quality control (QC) and regulatory applications of these formulations. A one-size-fits-all method seems unrealistic, as the selection of experimental conditions should resemble the physiological features exploited to trigger the release. This article reviews the state of the art for bio-predictive dissolution testing of colon-targeted products. Compendial methods overlook physiological aspects, such as buffer molarity and fluid composition. These are critical for pH-dependent products and time-controlled systems containing ionizable drugs. Moreover, meaningful methods for enzymatic-triggered products including either bacteria or enzymes are completely ignored by pharmacopeias. Bio-predictive testing may accelerate the development of successful products, although this may require complex methodologies. However, for high-throughput routine testing (e.g., QC), simplified methods can be used where balance is struck between simplicity, robustness and transferability on one side and bio-predictivity on the other. Ultimately, bio-predictive methods can occupy a special niche in terms of supplementing plasma concentration data for regulatory approval.
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Affiliation(s)
- Mauricio A. García
- Department of Biopharmaceutics and Pharmaceutical Technology, Johannes Gutenberg University Mainz, 55099 Mainz, Germany; (M.A.G.); (J.A.-G.)
| | - Felipe Varum
- Pharmaceutical Research and Development, F. Hoffmann-La Roche Ltd., 4070 Basel, Switzerland; (F.V.); (M.H.); (S.P.)
| | - Jozef Al-Gousous
- Department of Biopharmaceutics and Pharmaceutical Technology, Johannes Gutenberg University Mainz, 55099 Mainz, Germany; (M.A.G.); (J.A.-G.)
- Department of Pharmaceutical Sciences, University of Michigan, 428 Church Street, Ann Arbor, MI 48109, USA
| | - Michael Hofmann
- Pharmaceutical Research and Development, F. Hoffmann-La Roche Ltd., 4070 Basel, Switzerland; (F.V.); (M.H.); (S.P.)
| | - Susanne Page
- Pharmaceutical Research and Development, F. Hoffmann-La Roche Ltd., 4070 Basel, Switzerland; (F.V.); (M.H.); (S.P.)
| | - Peter Langguth
- Department of Biopharmaceutics and Pharmaceutical Technology, Johannes Gutenberg University Mainz, 55099 Mainz, Germany; (M.A.G.); (J.A.-G.)
- Correspondence:
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O'Farrell C, Stamatopoulos K, Simmons M, Batchelor H. In vitro models to evaluate ingestible devices: Present status and current trends. Adv Drug Deliv Rev 2021; 178:113924. [PMID: 34390774 DOI: 10.1016/j.addr.2021.113924] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2021] [Revised: 08/03/2021] [Accepted: 08/09/2021] [Indexed: 12/14/2022]
Abstract
Orally ingestible medical devices offer significant opportunity in the diagnosis and treatment of gastrointestinal conditions. Their development necessitates the use of models that simulate the gastrointestinal environment on both a macro and micro scale. An evolution in scientific technology has enabled a wide range of in vitro, ex vivo and in vivo models to be developed that replicate the gastrointestinal tract. This review describes the landscape of the existing range of in vitro tools that are available to characterize ingestible devices. Models are presented with details on their benefits and limitations with regards to the evaluation of ingestible devices and examples of their use in the evaluation of such devices is presented where available. The multitude of models available provides a suite of tools that can be used in the evaluation of ingestible devices that should be selected on the functionality of the device and the mechanism of its function.
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Affiliation(s)
- Connor O'Farrell
- School of Chemical Engineering, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
| | - Konstantinos Stamatopoulos
- School of Chemical Engineering, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK; Biopharmaceutics, Pharmaceutical Development, PDS, MST, RD Platform Technology & Science, GSK, David Jack Centre, Park Road, Ware, Hertfordshire SG12 0DP, UK
| | - Mark Simmons
- School of Chemical Engineering, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
| | - Hannah Batchelor
- Strathclyde Institute of Pharmacy and Biomedical Sciences, 161 Cathedral Street, Glasgow G4 0RE, UK.
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Weitschies W, Müller L, Grimm M, Koziolek M. Ingestible devices for studying the gastrointestinal physiology and their application in oral biopharmaceutics. Adv Drug Deliv Rev 2021; 176:113853. [PMID: 34192551 DOI: 10.1016/j.addr.2021.113853] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 06/22/2021] [Accepted: 06/23/2021] [Indexed: 12/17/2022]
Abstract
Ingestible sensor systems are unique tools for obtaining physiological data from an undisturbed gastrointestinal tract. Since their dimensions correspond to monolithic oral dosage forms, such as enteric coated tablets or hydrogel matrix tablets, they also allow insights into the physiological conditions experienced by non-disintegrating dosage forms on their way through the gastrointestinal tract. In this work, the different ingestible sensor systems which can be used for this purpose are described and their potential applications as well as difficulties and pitfalls with respect to their use are presented. It is also highlighted how the data on transit times, pH, temperature and pressure as well as the data from different animal models commonly used in drug product development such as dogs and pigs have contributed to a deeper mechanistic understanding of oral drug delivery.
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Affiliation(s)
- Werner Weitschies
- Institute of Pharmacy, Center of Drug Absorption and Transport, University of Greifswald, Greifswald, Germany.
| | - Laura Müller
- Institute of Pharmacy, Center of Drug Absorption and Transport, University of Greifswald, Greifswald, Germany
| | - Michael Grimm
- Institute of Pharmacy, Center of Drug Absorption and Transport, University of Greifswald, Greifswald, Germany
| | - Mirko Koziolek
- NCE Formulation Sciences, AbbVie Deutschland GmbH & Co. KG, Ludwigshafen, Germany
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Wagner C, Kesisoglou F, Pepin XJH, Parrott N, Emami Riedmaier A. Use of Physiologically Based Pharmacokinetic Modeling for Predicting Drug-Food Interactions: Recommendations for Improving Predictive Performance of Low Confidence Food Effect Models. AAPS JOURNAL 2021; 23:85. [PMID: 34142242 DOI: 10.1208/s12248-021-00601-0] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2021] [Accepted: 04/20/2021] [Indexed: 11/30/2022]
Abstract
Food can alter drug absorption and impact safety and efficacy. Besides conducting clinical studies, in vitro approaches such as biorelevant solubility and dissolution testing and in vivo dog studies are typical approaches to estimate a drug's food effect. The use of physiologically based pharmacokinetic models has gained importance and is nowadays a standard tool for food effect predictions at preclinical and clinical stages in the pharmaceutical industry. This manuscript is part of a broader publication from the IQ Consortium's food effect physiologically based pharmacokinetic model (PBPK) modeling working group and complements previous publications by focusing on cases where the food effect was predicted with low confidence. Pazopanib-HCl, trospium-Cl, and ziprasidone-HCl served as model compounds to provide insights into why several food effect predictions failed in the first instance. Furthermore, the manuscript depicts approaches whereby PBPK-based food effect predictions may be improved. These improvements should focus on the PBPK model functionality, especially better reflecting fasted- and fed-state gastric solubility, gastric re-acidification, and complex mechanisms related to gastric emptying of drugs. For improvement of in vitro methodologies, the focus should be on the development of more predictive solubility, supersaturation, and precipitation assays. With regards to the general PBPK modeling methodology, modelers should account for the full solubility profile when modeling ionizable compounds, including common ion effects, and apply a straightforward strategy to account for drug precipitation.
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Affiliation(s)
- Christian Wagner
- Pharmaceutical Technologies, Chemical and Pharmaceutical Development, Merck KGaA, Frankfurter Str. 250, 64293, Darmstadt, Germany.
| | | | - Xavier J H Pepin
- New Modalities and Parenteral Development, Pharmaceutical Technology & Development, Operations, AstraZeneca, Macclesfield, UK
| | - Neil Parrott
- Pharmaceutical Sciences, Roche Pharmaceutical Research and Early Development, Roche Innovation Center, Basel, Switzerland
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Freerks L, Zielke C, Tarnow MJ, Arien T, Mackie C, Inghelbrecht S, Klein S. A Toolbox for Mimicking Gastrointestinal Conditions in Children: Simulated Paediatric Breakfast Media (SPBM) for Addressing the Variability of Gastric Contents After Typical Paediatric Breakfasts. J Pharm Sci 2021; 111:51-61. [PMID: 34019904 DOI: 10.1016/j.xphs.2021.05.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Revised: 05/04/2021] [Accepted: 05/04/2021] [Indexed: 12/18/2022]
Abstract
Since co-administration of dosage forms with food can impact drug exposure, food effect studies became an integral part of oral drug product development. Studies are usually performed in healthy adults and the dosage form is co-administered with a high-fat high-calorie standard breakfast meal to mimic worst-case dosing conditions. A corresponding study design for children is lacking but would be essential for a proper risk-assessment in this vulnerable patient group. To protect healthy children from unnecessary in vivo studies, it would be even more desirable to predict food effects based on other than in vivo studies in the target age group. In the present study, typical children's breakfasts in different parts of the world were identified, prepared and physicochemical properties were assessed. Subsequently, Simulated Paediatric Breakfast Media (SPBM) resembling breakfast composition and properties were designed and applied in in vitro dissolution experiments mimicking the initial composition of the postprandial stomach after breakfast ingestion. Study results indicate the impact of different simulated gastric conditions on drug release. SPBM enabled to better estimate the variability of in vivo drug release in fed dosing conditions and their use will aid in better assessing food effects in children in different parts of the world.
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Affiliation(s)
- Lisa Freerks
- Department of Pharmacy, University of Greifswald, Institute of Biopharmaceutics and Pharmaceutical Technology, Center of Drug Absorption and Transport, 3 Felix Hausdorff Street, Greifswald 17489, Germany
| | - Carolin Zielke
- Department of Pharmacy, University of Greifswald, Institute of Biopharmaceutics and Pharmaceutical Technology, Center of Drug Absorption and Transport, 3 Felix Hausdorff Street, Greifswald 17489, Germany
| | - Marie-Josefin Tarnow
- Department of Pharmacy, University of Greifswald, Institute of Biopharmaceutics and Pharmaceutical Technology, Center of Drug Absorption and Transport, 3 Felix Hausdorff Street, Greifswald 17489, Germany
| | - Tina Arien
- Janssen Pharmaceutica NV, Turnhoutseweg 30, B-2340 Beerse, Belgium
| | - Claire Mackie
- Janssen Pharmaceutica NV, Turnhoutseweg 30, B-2340 Beerse, Belgium
| | | | - Sandra Klein
- Department of Pharmacy, University of Greifswald, Institute of Biopharmaceutics and Pharmaceutical Technology, Center of Drug Absorption and Transport, 3 Felix Hausdorff Street, Greifswald 17489, Germany.
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Vinarov Z, Abrahamsson B, Artursson P, Batchelor H, Berben P, Bernkop-Schnürch A, Butler J, Ceulemans J, Davies N, Dupont D, Flaten GE, Fotaki N, Griffin BT, Jannin V, Keemink J, Kesisoglou F, Koziolek M, Kuentz M, Mackie A, Meléndez-Martínez AJ, McAllister M, Müllertz A, O'Driscoll CM, Parrott N, Paszkowska J, Pavek P, Porter CJH, Reppas C, Stillhart C, Sugano K, Toader E, Valentová K, Vertzoni M, De Wildt SN, Wilson CG, Augustijns P. Current challenges and future perspectives in oral absorption research: An opinion of the UNGAP network. Adv Drug Deliv Rev 2021; 171:289-331. [PMID: 33610694 DOI: 10.1016/j.addr.2021.02.001] [Citation(s) in RCA: 64] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2020] [Revised: 01/12/2021] [Accepted: 02/01/2021] [Indexed: 02/06/2023]
Abstract
Although oral drug delivery is the preferred administration route and has been used for centuries, modern drug discovery and development pipelines challenge conventional formulation approaches and highlight the insufficient mechanistic understanding of processes critical to oral drug absorption. This review presents the opinion of UNGAP scientists on four key themes across the oral absorption landscape: (1) specific patient populations, (2) regional differences in the gastrointestinal tract, (3) advanced formulations and (4) food-drug interactions. The differences of oral absorption in pediatric and geriatric populations, the specific issues in colonic absorption, the formulation approaches for poorly water-soluble (small molecules) and poorly permeable (peptides, RNA etc.) drugs, as well as the vast realm of food effects, are some of the topics discussed in detail. The identified controversies and gaps in the current understanding of gastrointestinal absorption-related processes are used to create a roadmap for the future of oral drug absorption research.
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Affiliation(s)
- Zahari Vinarov
- Department of Pharmaceutical and Pharmacological Sciences, KU Leuven, Leuven, Belgium; Department of Chemical and Pharmaceutical Engineering, Sofia University, Sofia, Bulgaria
| | - Bertil Abrahamsson
- Oral Product Development, Pharmaceutical Technology & Development, Operations, AstraZeneca, Gothenburg, Sweden
| | - Per Artursson
- Department of Pharmacy, Uppsala University, Uppsala, Sweden
| | - Hannah Batchelor
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow, United Kingdom
| | - Philippe Berben
- Pharmaceutical Development, UCB Pharma SA, Braine- l'Alleud, Belgium
| | - Andreas Bernkop-Schnürch
- Department of Pharmaceutical Technology, Institute of Pharmacy, University of Innsbruck, Innsbruck, Austria
| | - James Butler
- GlaxoSmithKline Research and Development, Ware, United Kingdom
| | | | - Nigel Davies
- Advanced Drug Delivery, Pharmaceutical Sciences, R&D, AstraZeneca, Gothenburg, Sweden
| | | | - Gøril Eide Flaten
- Department of Pharmacy, UiT The Arctic University of Norway, Tromsø, Norway
| | - Nikoletta Fotaki
- Department of Pharmacy and Pharmacology, University of Bath, Bath, United Kingdom
| | | | | | | | | | | | - Martin Kuentz
- Institute for Pharma Technology, University of Applied Sciences and Arts Northwestern Switzerland, Basel, Switzerland
| | - Alan Mackie
- School of Food Science & Nutrition, University of Leeds, Leeds, United Kingdom
| | | | | | - Anette Müllertz
- Department of Pharmacy, University of Copenhagen, Copenhagen, Denmark
| | | | | | | | - Petr Pavek
- Faculty of Pharmacy, Charles University, Hradec Králové, Czech Republic
| | | | - Christos Reppas
- Department of Pharmacy, National and Kapodistrian University of Athens, Athens, Greece
| | | | - Kiyohiko Sugano
- College of Pharmaceutical Sciences, Ritsumeikan University, Shiga, Japan
| | - Elena Toader
- Faculty of Medicine, University of Medicine and Pharmacy of Iasi, Romania
| | - Kateřina Valentová
- Institute of Microbiology of the Czech Academy of Sciences, Prague, Czech Republic
| | - Maria Vertzoni
- Department of Pharmacy, National and Kapodistrian University of Athens, Athens, Greece
| | - Saskia N De Wildt
- Department of Pharmacology and Toxicology, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Clive G Wilson
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow, United Kingdom
| | - Patrick Augustijns
- Department of Pharmaceutical and Pharmacological Sciences, KU Leuven, Leuven, Belgium.
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14
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Preparation of delayed-release multiparticulate formulations of diclofenac sodium and evaluation of their dissolution characteristics using biorelevant dissolution methods. J Drug Deliv Sci Technol 2020. [DOI: 10.1016/j.jddst.2020.101986] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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15
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Freerks L, Sommerfeldt J, Löper PC, Klein S. Safe, swallowable and palatable paediatric mini-tablet formulations for a WHO model list of essential medicines for children compound – A promising starting point for future PUMA applications. Eur J Pharm Biopharm 2020; 156:11-19. [DOI: 10.1016/j.ejpb.2020.08.014] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2020] [Revised: 07/21/2020] [Accepted: 08/14/2020] [Indexed: 12/24/2022]
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16
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Amaral Silva D, Davies NM, Doschak MR, Al-Gousous J, Bou-Chacra N, Löbenberg R. Mechanistic understanding of underperforming enteric coated products: Opportunities to add clinical relevance to the dissolution test. J Control Release 2020; 325:323-334. [DOI: 10.1016/j.jconrel.2020.06.031] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2020] [Accepted: 06/26/2020] [Indexed: 02/04/2023]
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17
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Regulating the pH of bicarbonate solutions without purging gases: Application to dissolution testing of enteric coated tablets, pellets and microparticles. Int J Pharm 2020; 585:119562. [PMID: 32565282 DOI: 10.1016/j.ijpharm.2020.119562] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Revised: 06/14/2020] [Accepted: 06/15/2020] [Indexed: 12/14/2022]
Abstract
Dissolution media based on bicarbonate buffers closely mimic the environment of intestinal fluids and thus improve in vitro in vivo correlation compared to phosphate buffers. Purging gases into the medium is used as a method to stabilise bicarbonate buffers; however, this causes issues due to the disturbance of the hydrodynamics in the dissolution vessel. The aim of this study was to develop a novel system to regulate and stabilise the pH of bicarbonate buffers without purging gases for the application of dissolution testing of enteric coated products. A novel enclosure system was applied to the USP II dissolution vessel to supply N2 and CO2 gases above the dissolution medium without purging into the solution. Drug release from enteric coated predinisolone microparticles (216.9 µm), pellets (1.25 mm) and commercially available tablets was determined in 0.1 M HCl and subsequently in pH 6.8 phosphate buffer or pH 6.2-6.8 bicarbonate buffers generated by titration of the acidic medium in situ using USP II apparatus. Supplying N2 at 3-4 bar and CO2 at 0.1 bar were able to increase the pH of the bicarbonate buffer from pH 6.2 to 6.8 within 45 min and subsequently stabilise the medium pH at 6.8 ± 0.05 pH units. Enteric coated microparticles showed much faster drug release in the physiological bicarbonate buffers than tablets and pellets. The novel bicarbonate-based dissolution system moves forward the application of the physiological bicarbonate buffers for testing pharmaceutical products to meet compendial requirements.
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18
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Broesder A, Woerdenbag HJ, Prins GH, Nguyen DN, Frijlink HW, Hinrichs WLJ. pH-dependent ileocolonic drug delivery, part I: in vitro and clinical evaluation of novel systems. Drug Discov Today 2020; 25:1362-1373. [PMID: 32554060 DOI: 10.1016/j.drudis.2020.06.011] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Revised: 05/18/2020] [Accepted: 06/08/2020] [Indexed: 02/07/2023]
Abstract
After the pH dependency of novel pH-dependent ileocolonic drug delivery systems is confirmed in vitro, their performance should be evaluated in human volunteers.
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Affiliation(s)
- Annemarie Broesder
- University of Groningen, Groningen Research Institute of Pharmacy, Department of Pharmaceutical Technology and Biopharmacy, Antonius Deusinglaan 1, 9713 AV Groningen, The Netherlands
| | - Herman J Woerdenbag
- University of Groningen, Groningen Research Institute of Pharmacy, Department of Pharmaceutical Technology and Biopharmacy, Antonius Deusinglaan 1, 9713 AV Groningen, The Netherlands
| | - Grietje H Prins
- University of Groningen, Groningen Research Institute of Pharmacy, Department of Pharmaceutical Technology and Biopharmacy, Antonius Deusinglaan 1, 9713 AV Groningen, The Netherlands
| | - Duong N Nguyen
- University of Groningen, Groningen Research Institute of Pharmacy, Department of Pharmaceutical Technology and Biopharmacy, Antonius Deusinglaan 1, 9713 AV Groningen, The Netherlands
| | - Henderik W Frijlink
- University of Groningen, Groningen Research Institute of Pharmacy, Department of Pharmaceutical Technology and Biopharmacy, Antonius Deusinglaan 1, 9713 AV Groningen, The Netherlands
| | - Wouter L J Hinrichs
- University of Groningen, Groningen Research Institute of Pharmacy, Department of Pharmaceutical Technology and Biopharmacy, Antonius Deusinglaan 1, 9713 AV Groningen, The Netherlands.
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19
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Bermejo M, Sanchez-Dengra B, Gonzalez-Alvarez M, Gonzalez-Alvarez I. Oral controlled release dosage forms: dissolution versus diffusion. Expert Opin Drug Deliv 2020; 17:791-803. [DOI: 10.1080/17425247.2020.1750593] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Affiliation(s)
- Marival Bermejo
- Department of Engineering, Pharmacokinetics and Pharmaceutical Technology Area, Miguel Hernandez University, Elche, Spain
| | - Barbara Sanchez-Dengra
- Department of Engineering, Pharmacokinetics and Pharmaceutical Technology Area, Miguel Hernandez University, Elche, Spain
| | - Marta Gonzalez-Alvarez
- Department of Engineering, Pharmacokinetics and Pharmaceutical Technology Area, Miguel Hernandez University, Elche, Spain
| | - Isabel Gonzalez-Alvarez
- Department of Engineering, Pharmacokinetics and Pharmaceutical Technology Area, Miguel Hernandez University, Elche, Spain
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20
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Maderuelo C, Lanao JM, Zarzuelo A. Enteric coating of oral solid dosage forms as a tool to improve drug bioavailability. Eur J Pharm Sci 2019; 138:105019. [DOI: 10.1016/j.ejps.2019.105019] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2019] [Revised: 07/10/2019] [Accepted: 07/28/2019] [Indexed: 02/07/2023]
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21
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Hamed R. Physiological parameters of the gastrointestinal fluid impact the dissolution behavior of the BCS class IIa drug valsartan. Pharm Dev Technol 2019; 23:1168-1176. [PMID: 30320540 DOI: 10.1080/10837450.2018.1536996] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
The objective of this study was to investigate the effect of the physiological parameters (pH, buffer capacity, and ionic strength) of the gastrointestinal (GI) fluid on the dissolution behavior of the class II weakly acidic (BCS class IIa) drug valsartan. A series of in vitro dissolution studies was carried out on Diovan® immediate release tablets using media that cover the physiological range of pH (1.2-7.8), buffer capacity (0-0.047 M/ΔpH), and ionic strength (0-0.4 mol/L) of the GI fluid during fasted and fed states using the conventional USP II apparatus. Valsartan exhibited pH- and buffer capacity-dependent dissolution behavior, where valsartan release was slow and incomplete in media simulating gastric fluid with low pH, and fast and complete in media simulating intestinal fluid with high pH. In addition, the rate of valsartan release increased with increasing the buffer capacity of the dissolution medium. In water and NaCl solutions, valsartan release was incomplete and the dissolution profiles were similar regardless of the ionic strength of the medium, indicating an ionic strength-independent dissolution behavior. These results highlight the significant effect of the physiological parameters of the GI fluid on the dissolution behavior of BCS class IIa drugs.
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Affiliation(s)
- Rania Hamed
- a Department of Pharmacy, Faculty of Pharmacy , Al-Zaytoonah University of Jordan , Amman , Jordan
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22
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Jede C, Wagner C, Kubas H, Weigandt M, Weber C, Lecomte M, Badolo L, Koziolek M, Weitschies W. Improved Prediction of in Vivo Supersaturation and Precipitation of Poorly Soluble Weakly Basic Drugs Using a Biorelevant Bicarbonate Buffer in a Gastrointestinal Transfer Model. Mol Pharm 2019; 16:3938-3947. [PMID: 31335153 DOI: 10.1021/acs.molpharmaceut.9b00534] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The characterization of intestinal dissolution of poorly soluble drugs represents a key task during the development of both new drug candidates and drug products. The bicarbonate buffer is considered as the most biorelevant buffer for simulating intestinal conditions. However, because of its complex nature, being the volatility of CO2, it has only been rarely used in the past. The aim of this study was to investigate the effect of a biorelevant bicarbonate buffer on intestinal supersaturation and precipitation of poorly soluble drugs using a gastrointestinal (GI) transfer model. Therefore, the results of ketoconazole, pazopanib, and lapatinib transfer model experiments using FaSSIFbicarbonate were compared with the results obtained using standard FaSSIFphosphate. Additionally, the effect of hydroxypropyl methylcellulose acetate succinate (HPMCAS) as a precipitation inhibitor was investigated in both buffer systems and compared to rat pharmacokinetic (PK) studies with and without coadministration of HPMCAS as a precipitation inhibitor. While HPMCAS was found to be an effective precipitation inhibitor for all drugs in FaSSIFphosphate, the effect in FaSSIFbicarbonate was much less pronounced. The PK studies revealed that HPMCAS did not increase the exposure of any of the model compounds significantly, indicating that the transfer model employing bicarbonate-buffered FaSSIF has a better predictive power compared to the model using phosphate-buffered FaSSIF. Hence, the application of a bicarbonate buffer in a transfer model set-up represents a promising approach to increase the predictive power of this in vitrotool and to contribute to the development of drug substances and drug products in a more biorelevant way.
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Affiliation(s)
- Christian Jede
- Institute of Pharmacy, Department of Biopharmaceutics and Pharmaceutical Technology , University of Greifswald , Felix-Hausdorff-Straße 3 , 17489 Greifswald , Germany
| | | | | | | | | | | | | | - Mirko Koziolek
- Institute of Pharmacy, Department of Biopharmaceutics and Pharmaceutical Technology , University of Greifswald , Felix-Hausdorff-Straße 3 , 17489 Greifswald , Germany
| | - Werner Weitschies
- Institute of Pharmacy, Department of Biopharmaceutics and Pharmaceutical Technology , University of Greifswald , Felix-Hausdorff-Straße 3 , 17489 Greifswald , Germany
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23
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Amaral Silva D, Al-Gousous J, Davies NM, Bou Chacra N, Webster GK, Lipka E, Amidon G, Löbenberg R. Simulated, biorelevant, clinically relevant or physiologically relevant dissolution media: The hidden role of bicarbonate buffer. Eur J Pharm Biopharm 2019; 142:8-19. [PMID: 31195131 DOI: 10.1016/j.ejpb.2019.06.006] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2019] [Revised: 06/04/2019] [Accepted: 06/08/2019] [Indexed: 01/15/2023]
Abstract
In-vitro dissolution testing of pharmaceutical formulations has been used as a quality control test for many years. At early drug product development, in vivo predictive dissolution testing can be used for guidance in the rational selection of candidate formulations that best fit the desired in vivo dissolution characteristics. At present, the most widely applied dissolution media are phosphate-based buffers and, in some cases, the result of dissolution tests performed in such media have demonstrated reasonable/acceptable IVIVCs. However, the presence of phosphates in human GI luminal fluids is insignificant, which makes the use of such media poorly representative of the in vivo environment. The gastrointestinal lumen has long been shown to be buffered by bicarbonate. Hence, much interest in the development of suitable biorelevant in vitro dissolution media based on bicarbonate buffer systems has evolved. However, there are inherent difficulties associated with these buffers, such as maintaining the pH throughout the dissolution test, as CO2 tends to leave the system. Various mathematical models have been proposed to analyze bicarbonate buffers and they are discussed in this review. Approaches such as using simpler buffer systems instead of bicarbonate have been proposed as surrogate buffers to produce an equivalent buffer effect on drug dissolution on a case-by-case basis. There are many drawbacks related to simpler buffers systems including their poor in vivo predictability. Considerable discrepancies between phosphate and bicarbonate buffer dissolution results have been reported for certain dosage forms, e.g. enteric coated formulations. The role and need of bicarbonate-based buffers in quality control testing requires scientific analysis. This review also encompasses on the use of bicarbonate-based buffers as a potentially in vivo predictive dissolution medium for enteric coated dosage forms.
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Affiliation(s)
- Daniela Amaral Silva
- Faculty of Pharmacy & Pharmaceutical Sciences, University of Alberta, Edmonton, Alberta, Canada
| | - Jozef Al-Gousous
- College of Pharmacy, University of Michigan, Ann Arbor, MI, United States
| | - Neal M Davies
- Faculty of Pharmacy & Pharmaceutical Sciences, University of Alberta, Edmonton, Alberta, Canada
| | - Nadia Bou Chacra
- Faculty of Pharmaceutical Sciences, University of Sao Paulo, Sao Paulo, SP, Brazil
| | - Gregory K Webster
- Research and Development, AbbVie Inc., North Chicago, IL, United States
| | | | - Gordon Amidon
- College of Pharmacy, University of Michigan, Ann Arbor, MI, United States
| | - Raimar Löbenberg
- Faculty of Pharmacy & Pharmaceutical Sciences, University of Alberta, Edmonton, Alberta, Canada.
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24
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Al-Gousous J, Salehi N, Amidon GE, Ziff RM, Langguth P, Amidon GL. Mass Transport Analysis of Bicarbonate Buffer: Effect of the CO 2-H 2CO 3 Hydration-Dehydration Kinetics in the Fluid Boundary Layer and the Apparent Effective p K a Controlling Dissolution of Acids and Bases. Mol Pharm 2019; 16:2626-2635. [PMID: 31013101 DOI: 10.1021/acs.molpharmaceut.9b00187] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The main buffering system influencing ionizable drug dissolution in the human intestinal fluid is bicarbonate-based; however, it is rarely used in routine pharmaceutical practice due to the volatility of dissolved CO2. The typical pharmaceutical buffers used fail to capture the unique aspects of the hydration-dehydration kinetics of the bicarbonate-CO2 system. In particular, CO2 is involved in a reversible interconversion with carbonic acid (H2CO3), which is the actual conjugate acid of the system, as follows CO2 + H2O ⇌ H2CO3. In contrast to ionization reactions, this interconversion does not equilibrate very rapidly compared to the diffusional processes through a typical fluid diffusion boundary layer at a solid-liquid interface. In this report, a mathematical mass transport analysis was developed for ionizable drug dissolution in bicarbonate using the rules of conservation of mass and electric charge in addition to accounting for the diffusional times and reaction rate constants of the CO2-H2CO3 interconversion. This model, which includes both the hydration reaction rate and dehydration reaction rate, we called the "reversible non-equilibrium" (RNE) model. The predictions made by this RNE approach for ionizable drug dissolution rates were compared to the experimental data generated by an intrinsic dissolution method for three ionizable drugs, indomethacin, ibuprofen, and haloperidol. The results demonstrate the superiority of predictions for the RNE approach compared to the predictions of a model assuming equilibrium between CO2 and H2CO3, as well as models ignoring reactions. The analysis also shows that bicarbonate buffer can be viewed as having an effective p Ka in the boundary layer that is different from that in bulk and is hydrodynamics-dependent.
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Affiliation(s)
- Jozef Al-Gousous
- Department of Pharmaceutical Sciences , University of Michigan , 428 Church Street , Ann Arbor , Michigan 48109 , United States
| | - Niloufar Salehi
- Department of Chemical Engineering , University of Michigan , 2300 Hayward Street , Ann Arbor , Michigan 48109 , United States
| | - Gregory E Amidon
- Department of Pharmaceutical Sciences , University of Michigan , 428 Church Street , Ann Arbor , Michigan 48109 , United States
| | - Robert M Ziff
- Department of Chemical Engineering , University of Michigan , 2300 Hayward Street , Ann Arbor , Michigan 48109 , United States
| | - Peter Langguth
- Institute of Pharmacy and Biochemistry , Johannes Gutenberg University Mainz , Staudingerweg 5 , 55128 Mainz , Germany
| | - Gordon L Amidon
- Department of Pharmaceutical Sciences , University of Michigan , 428 Church Street , Ann Arbor , Michigan 48109 , United States
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25
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Mahasti NN, Shih YJ, Huang YH. Removal of iron as oxyhydroxide (FeOOH) from aqueous solution by fluidized-bed homogeneous crystallization. J Taiwan Inst Chem Eng 2019. [DOI: 10.1016/j.jtice.2018.12.022] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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26
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Karkossa F, Klein S. Individualized in vitro and in silico methods for predicting in vivo performance of enteric-coated tablets containing a narrow therapeutic index drug. Eur J Pharm Biopharm 2018; 135:13-24. [PMID: 30529296 DOI: 10.1016/j.ejpb.2018.12.004] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2018] [Revised: 10/23/2018] [Accepted: 12/04/2018] [Indexed: 12/26/2022]
Abstract
The efficacy of narrow therapeutic index (NTI) drugs is closely related to their plasma concentration-time profile. Particularly for these compounds interindividual variability of gastrointestinal (GI) parameters relevant to in vivo drug release may result in fluctuations of the plasma concentration. The present study focused on assessing the influence of individual GI pH- and transit profiles on drug release of enteric valproate tablet formulations by means of individualized in vitro dissolution experiments. After initial experiments simulating GI passages in average healthy adults, a novel in vitro dissolution model was used to simulate individual GI pH- and transit profiles with physiologically relevant dissolution media. Based on the dissolution profiles obtained in these experiments, individual in silico plasma profiles were generated and compared to fasted in vivo data applying a mean Euclidean distance approach. Simulated individual gastric residence time was identified as crucial parameter determining the onset of absorption, whereas the shape of the plasma profile is mainly influenced by individual valproate pharmacokinetics. The novel in vitro and in silico methods used in this study are promising tools for estimating in vivo drug release and plasma concentration in individual subjects and thus may contribute to a prospective risk assessment for NTI formulations.
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Affiliation(s)
- Frank Karkossa
- University of Greifswald, Department of Pharmacy, Institute of Biopharmaceutics and Pharmaceutical Technology, Center of Drug Absorption and Transport (C_DAT), Felix-Hausdorff-Straße 3, 17489 Greifswald, Germany
| | - Sandra Klein
- University of Greifswald, Department of Pharmacy, Institute of Biopharmaceutics and Pharmaceutical Technology, Center of Drug Absorption and Transport (C_DAT), Felix-Hausdorff-Straße 3, 17489 Greifswald, Germany.
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27
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Al-Gousous J, Sun KX, McNamara DP, Hens B, Salehi N, Langguth P, Bermejo M, Amidon GE, Amidon GL. Mass Transport Analysis of the Enhanced Buffer Capacity of the Bicarbonate-CO 2 Buffer in a Phase-Heterogenous System: Physiological and Pharmaceutical Significance. Mol Pharm 2018; 15:5291-5301. [PMID: 30362350 DOI: 10.1021/acs.molpharmaceut.8b00783] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The bicarbonate buffer capacity is usually considered in a phase-homogeneous system, at equilibrium, with no CO2 transfer between the liquid buffer phase and another phase. However, typically, an in vitro bicarbonate buffer-based system is a phase-heterogeneous system, as it entails continuously sparging (bubbling) the dissolution medium with CO2 in a gas mixture, at constant ratio, to maintain a constant partial pressure of CO2 (g) and CO2(aq) molarity at a prescribed value, with CO2 diffusing freely between the gas and the aqueous phases. The human gastrointestinal tract is also a phase-heterogeneous system, with CO2 diffusing across the mucosal membrane into the mesenteric arterial blood, which serves as a sink for CO2 from the intestinal lumen. In this report, a mass transport analysis of the apparent buffer capacity of a phase-heterogeneous bicarbonate-CO2 system is developed. It is shown that, most significantly, a phase-heterogeneous bicarbonate-CO2 system can have a much higher buffer capacity than a phase-homogeneous system such that the buffer capacity is dependent on the bicarbonate concentration. It is double that of a phase-homogeneous system at the pH = p Ka for a monoprotic buffer at the same concentration. This buffer capacity enhancement increases hyperbolically with pH above the p Ka, thus providing a much stronger buffering to keep the pH in the physiologically neutral range. The buffer capacity will be dependent on the bicarbonate molarity (which in vivo will depend on the bicarbonate secretion rate) and not the pH of the luminal fluid. Further, there is no conjugate acid accumulation as a result of bicarbonate neutralization, since the resulting carbonic acid (H2CO3) rapidly dehydrates producing CO2 and H2O. The mass transport analysis developed in this report is further supported by in vitro experimental results. This enhanced bicarbonate buffer capacity in a phase-heterogeneous system is of physiological significance as well as significant for the dissolution and absorption of ionizable drugs.
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Affiliation(s)
- Jozef Al-Gousous
- University of Michigan , College of Pharmacy, Department of Pharmaceutical Sciences , 428 Church Street, Room 4002 , Ann Arbor , Michigan 48109 , United States
| | - Kathy X Sun
- University of Michigan , College of Pharmacy, Department of Pharmaceutical Sciences , 428 Church Street, Room 4002 , Ann Arbor , Michigan 48109 , United States
| | - Daniel P McNamara
- Drug Product Science and Technology , Bristol-Myers Squibb , 1 Squibb Drive , New Brunswick , New Jersey 08903 , United States
| | - Bart Hens
- University of Michigan , College of Pharmacy, Department of Pharmaceutical Sciences , 428 Church Street, Room 4002 , Ann Arbor , Michigan 48109 , United States
| | - Niloufar Salehi
- University of Michigan , College of Pharmacy, Department of Pharmaceutical Sciences , 428 Church Street, Room 4002 , Ann Arbor , Michigan 48109 , United States
| | - Peter Langguth
- Johannes Gutenberg Universität Mainz, Fachbereich Chemie Pharmazie und Geowissenschaften , Department of Biopharmaceutics and Pharmaceutical Technology , D-55099 Mainz , Germany
| | - Marival Bermejo
- Universidad Miguel Hernández , Ingenieria: Area Farmacia , Ctra. Alicante-Valencia N 332 , 03550 Sant Joan d'Alacant , Spain
| | - Gregory E Amidon
- University of Michigan , College of Pharmacy, Department of Pharmaceutical Sciences , 428 Church Street, Room 4002 , Ann Arbor , Michigan 48109 , United States
| | - Gordon L Amidon
- University of Michigan , College of Pharmacy, Department of Pharmaceutical Sciences , 428 Church Street, Room 4002 , Ann Arbor , Michigan 48109 , United States
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28
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Karkossa F, Klein S. A Biopredictive In Vitro Comparison of Oral Locally Acting Mesalazine Formulations by a Novel Dissolution Model for Assessing Intraluminal Drug Release in Individual Subjects. J Pharm Sci 2018; 107:1680-1689. [DOI: 10.1016/j.xphs.2018.02.016] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2018] [Revised: 02/12/2018] [Accepted: 02/21/2018] [Indexed: 01/07/2023]
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29
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Hens B, Talattof A, Paixão P, Bermejo M, Tsume Y, Löbenberg R, Amidon GL. Measuring the Impact of Gastrointestinal Variables on the Systemic Outcome of Two Suspensions of Posaconazole by a PBPK Model. AAPS JOURNAL 2018; 20:57. [DOI: 10.1208/s12248-018-0217-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2018] [Accepted: 03/07/2018] [Indexed: 01/08/2023]
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Hens B, Tsume Y, Bermejo M, Paixao P, Koenigsknecht MJ, Baker JR, Hasler WL, Lionberger R, Fan J, Dickens J, Shedden K, Wen B, Wysocki J, Loebenberg R, Lee A, Frances A, Amidon G, Yu A, Benninghoff G, Salehi N, Talattof A, Sun D, Amidon GL. Low Buffer Capacity and Alternating Motility along the Human Gastrointestinal Tract: Implications for in Vivo Dissolution and Absorption of Ionizable Drugs. Mol Pharm 2017; 14:4281-4294. [PMID: 28737409 DOI: 10.1021/acs.molpharmaceut.7b00426] [Citation(s) in RCA: 85] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
In this study, we determined the pH and buffer capacity of human gastrointestinal (GI) fluids (aspirated from the stomach, duodenum, proximal jejunum, and mid/distal jejunum) as a function of time, from 37 healthy subjects after oral administration of an 800 mg immediate-release tablet of ibuprofen (reference listed drug; RLD) under typical prescribed bioequivalence (BE) study protocol conditions in both fasted and fed states (simulated by ingestion of a liquid meal). Simultaneously, motility was continuously monitored using water-perfused manometry. The time to appearance of phase III contractions (i.e., housekeeper wave) was monitored following administration of the ibuprofen tablet. Our results clearly demonstrated the dynamic change in pH as a function of time and, most significantly, the extremely low buffer capacity along the GI tract. The buffer capacity on average was 2.26 μmol/mL/ΔpH in fasted state (range: 0.26 and 6.32 μmol/mL/ΔpH) and 2.66 μmol/mL/ΔpH in fed state (range: 0.78 and 5.98 μmol/mL/ΔpH) throughout the entire upper GI tract (stomach, duodenum, and proximal and mid/distal jejunum). The implication of this very low buffer capacity of the human GI tract is profound for the oral delivery of both acidic and basic active pharmaceutical ingredients (APIs). An in vivo predictive dissolution method would require not only a bicarbonate buffer but also, more significantly, a low buffer capacity of dissolution media to reflect in vivo dissolution conditions.
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Affiliation(s)
- Bart Hens
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Michigan , Ann Arbor, Michigan 48109, United States
| | - Yasuhiro Tsume
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Michigan , Ann Arbor, Michigan 48109, United States
| | - Marival Bermejo
- Department of Engineering, Pharmacy Section, Miguel Hernandez University , San Juan de Alicante, 03550 Alicante, Spain
| | - Paulo Paixao
- Research Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy, Universidade de Lisboa , Avenida Professor Gama Pinto, 1649-003 Lisboa, Portugal
| | - Mark J Koenigsknecht
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Michigan , Ann Arbor, Michigan 48109, United States
| | - Jason R Baker
- Department of Internal Medicine, Division of Gastroenterology, University of Michigan , Ann Arbor, Michigan 48109, United States
| | - William L Hasler
- Department of Internal Medicine, Division of Gastroenterology, University of Michigan , Ann Arbor, Michigan 48109, United States
| | - Robert Lionberger
- Office of Generic Drugs, Center for Drug Evaluation and Research, U.S. Food and Drug Administration , Silver Spring, Maryland 20993, United States
| | - Jianghong Fan
- Office of Generic Drugs, Center for Drug Evaluation and Research, U.S. Food and Drug Administration , Silver Spring, Maryland 20993, United States
| | - Joseph Dickens
- Department of Statistics, University of Michigan , Ann Arbor, Michigan 48109, United States
| | - Kerby Shedden
- Department of Statistics, University of Michigan , Ann Arbor, Michigan 48109, United States
| | - Bo Wen
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Michigan , Ann Arbor, Michigan 48109, United States
| | - Jeffrey Wysocki
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Michigan , Ann Arbor, Michigan 48109, United States
| | - Raimar Loebenberg
- Faculty of Pharmacy & Pharmaceutical Sciences, University of Alberta , Edmonton, Alberta, Canada T6G 2H7
| | - Allen Lee
- Department of Engineering, Pharmacy Section, Miguel Hernandez University , San Juan de Alicante, 03550 Alicante, Spain
| | - Ann Frances
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Michigan , Ann Arbor, Michigan 48109, United States
| | - Greg Amidon
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Michigan , Ann Arbor, Michigan 48109, United States
| | - Alex Yu
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Michigan , Ann Arbor, Michigan 48109, United States
| | - Gail Benninghoff
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Michigan , Ann Arbor, Michigan 48109, United States
| | - Niloufar Salehi
- Center for the Study of Complex Systems and Department of Chemical Engineering, University of Michigan , Ann Arbor, Michigan 48109-2136, United States
| | - Arjang Talattof
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Michigan , Ann Arbor, Michigan 48109, United States
| | - Duxin Sun
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Michigan , Ann Arbor, Michigan 48109, United States
| | - Gordon L Amidon
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Michigan , Ann Arbor, Michigan 48109, United States
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Karkossa F, Klein S. Assessing the influence of media composition and ionic strength on drug release from commercial immediate-release and enteric-coated aspirin tablets. J Pharm Pharmacol 2017; 69:1327-1340. [DOI: 10.1111/jphp.12777] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Accepted: 05/28/2017] [Indexed: 12/01/2022]
Abstract
Abstract
Objectives
The objective of this test series was to elucidate the importance of selecting the right media composition for a biopredictive in-vitro dissolution screening of enteric-coated dosage forms.
Methods
Drug release from immediate-release (IR) and enteric-coated (EC) aspirin formulations was assessed in phosphate-based and bicarbonate-based media with different pH, electrolyte composition and ionic strength.
Key findings
Drug release from aspirin IR tablets was unaffected by media composition. In contrast, drug release from EC aspirin formulations was affected by buffer species and ionic strength. In all media, drug release increased with increasing ionic strength, but in bicarbonate-based buffers was delayed when compared with that in phosphate-based buffers. Interestingly, the cation species in the dissolution medium had also a clear impact on drug release. Drug release profiles obtained in Blank CarbSIF, a new medium simulating pH and average ionic composition of small intestinal fluid, were different from those obtained in all other buffer compositions studied.
Conclusions
Results from this study in which the impact of various media parameters on drug release of EC aspirin formulations was systematically screened clearly show that when developing predictive dissolution tests, it is important to simulate the ionic composition of intraluminal fluids as closely as possible.
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Affiliation(s)
- Frank Karkossa
- Department of Pharmacy, Institute of Biopharmaceutics and Pharmaceutical Technology, Center of Drug Absorption and Transport (C_DAT), University of Greifswald, Greifswald, Germany
| | - Sandra Klein
- Department of Pharmacy, Institute of Biopharmaceutics and Pharmaceutical Technology, Center of Drug Absorption and Transport (C_DAT), University of Greifswald, Greifswald, Germany
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Kos P, Pavli M, Baumgartner S, Kogej K. Release mechanism of doxazosin from carrageenan matrix tablets: Effect of ionic strength and addition of sodium dodecyl sulphate. Int J Pharm 2017. [PMID: 28648579 DOI: 10.1016/j.ijpharm.2017.06.067] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
The polyelectrolyte matrix tablets loaded with an oppositely charged drug exhibit complex drug-release mechanisms. In this study, the release mechanism of a cationic drug doxazosin mesylate (DM) from matrix tablets based on an anionic polyelectrolyte λ-carrageenan (λ-CARR) is investigated. The drug release rates from λ-CARR matrices are correlated with binding results based on potentiometric measurements using the DM ion-sensitive membrane electrode and with molecular characteristics of the DM-λ-CARR-complex particles through hydrodynamic size measurements. Experiments are performed in solutions with different ionic strength and with the addition of an anionic surfactant sodium dodecyl sulphate (SDS). It is demonstrated that in addition to swelling and erosion of tablets, the release rates depend strongly on cooperative interactions between DM and λ-CARR. Addition of SDS at concentrations below its critical micelle concentration (CMC) slows down the DM release through hydrophobic binding of SDS to the DM-λ-CARR complex. On the contrary, at concentrations above the CMC SDS pulls DM from the complex by forming mixed micelles with it and thus accelerates the release. Results involving SDS show that the concentration of surfactants that are naturally present in gastrointestinal environment may have a great impact on the drug release process.
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Affiliation(s)
- Petra Kos
- Faculty of Pharmacy, University of Ljubljana, Aškerčeva 7, SI-1000 Ljubljana, Slovenia
| | - Matej Pavli
- Faculty of Pharmacy, University of Ljubljana, Aškerčeva 7, SI-1000 Ljubljana, Slovenia; Krka d.d., Novo mesto, Šmarješka cesta 6, SI-8501 Novo mesto, Slovenia
| | - Saša Baumgartner
- Faculty of Pharmacy, University of Ljubljana, Aškerčeva 7, SI-1000 Ljubljana, Slovenia
| | - Ksenija Kogej
- Department of Chemistry and Biochemistry, Faculty of Chemistry and Chemical Technology, University of Ljubljana, Večna pot 113, SI-1000 Ljubljana, Slovenia.
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Bou-Chacra N, Melo KJC, Morales IAC, Stippler ES, Kesisoglou F, Yazdanian M, Löbenberg R. Evolution of Choice of Solubility and Dissolution Media After Two Decades of Biopharmaceutical Classification System. AAPS JOURNAL 2017; 19:989-1001. [DOI: 10.1208/s12248-017-0085-5] [Citation(s) in RCA: 55] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2016] [Accepted: 04/11/2017] [Indexed: 11/30/2022]
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34
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Hamed R, AlJanabi R, Sunoqrot S, Abbas A. The effect of pH, buffer capacity and ionic strength on quetiapine fumarate release from matrix tablets prepared using two different polymeric blends. Drug Dev Ind Pharm 2017; 43:1330-1342. [DOI: 10.1080/03639045.2017.1318897] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Affiliation(s)
- Rania Hamed
- Department of Pharmacy, Faculty of Pharmacy, Al-Zaytoonah University of Jordan, Amman, Jordan
| | - Reem AlJanabi
- Department of Pharmacy, Faculty of Pharmacy, Al-Zaytoonah University of Jordan, Amman, Jordan
| | - Suhair Sunoqrot
- Department of Pharmacy, Faculty of Pharmacy, Al-Zaytoonah University of Jordan, Amman, Jordan
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Al-Gousous J, Tsume Y, Fu M, Salem II, Langguth P. Unpredictable Performance of pH-Dependent Coatings Accentuates the Need for Improved Predictive in Vitro Test Systems. Mol Pharm 2017; 14:4209-4219. [PMID: 28199791 DOI: 10.1021/acs.molpharmaceut.6b00877] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
First introduced in the second half of the 19th century, enteric coatings are commonly used to protect acid-labile drugs, reduce the risk of gastric side effects due to irritating drugs, or for local drug delivery to the lower gastrointestinal (GI) tract. The currently available enteric-coatings are based on pH-sensitive weakly acidic polymers. Despite the long history of their use, the causes behind their performance often being unpredictable have not been properly investigated with most of the attention being focused only on the gastric emptying. However, little attention has been given to the postgastric emptying disintegration and dissolution of these dosage forms. This lack of attention has contributed to the difficulty in predicting the in vivo behavior of these dosage forms and to cases of bioavailability problems with some enteric-coated products. Therefore, increased attention needs to be given to this issue.
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Affiliation(s)
- Jozef Al-Gousous
- Institute of Pharmacy and Biochemistry, Johannes Gutenberg University Mainz , Staudinger Weg 5, 55099 Mainz, Germany
| | - Yasuhiro Tsume
- Department of Pharmaceutical Sciences, University of Michigan , Ann Arbor, Michigan 48109, United States
| | - Maoqi Fu
- Institute of Pharmacy and Biochemistry, Johannes Gutenberg University Mainz , Staudinger Weg 5, 55099 Mainz, Germany
| | - Isam I Salem
- International Pharmaceutical Research Center , 1 Queen Rania Street, Amman 11196, Jordan
| | - Peter Langguth
- Institute of Pharmacy and Biochemistry, Johannes Gutenberg University Mainz , Staudinger Weg 5, 55099 Mainz, Germany
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36
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Karkossa F, Krueger A, Urbaniak J, Klein S. Simulating Different Dosing Scenarios for a Child-Appropriate Valproate ER Formulation in a New Pediatric Two-Stage Dissolution Model. AAPS PharmSciTech 2017; 18:309-316. [PMID: 27909943 DOI: 10.1208/s12249-016-0671-3] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2016] [Accepted: 11/13/2016] [Indexed: 11/30/2022] Open
Abstract
Predictive in vitro test methods addressing the parameters relevant to drug release in the pediatric gastrointestinal tract could be an appropriate means for reducing the number of in vivo studies in children. However, dissolution models addressing the particular features of pediatric gastrointestinal physiology and typical pediatric dosing scenarios have not yet been described. The objective of the present study was to combine the knowledge on common vehicle types and properties and current information on pediatric gastrointestinal physiology to design a dissolution model that enables a biorelevant simulation of the gastrointestinal conditions in young children. The novel dissolution setup consists of a miniaturized dissolution system allowing the use of small fluid volumes, physiological bicarbonate-based test media, and a proper pH control during the experiment using a pHysio-stat® device. Following design and assembly of the novel in vitro setup, a set of experiments screening in vitro drug release from a valproate-extended release formulation under typical dosing conditions in infants was performed. In vitro drug release profiles indicated a controlled drug release of the test product over 12 h and were in good agreement with information given in the Summary of Product Characteristics and the Patient Information Leaflet, as well as with results from an in vivo food effect study performed with the same product and reported in the literature. The new dissolution setup thus represents a promising in vitro screening tool in the development of pediatric dosage forms and may help to reduce the number of pharmacokinetic studies in children.
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Koziolek M, Grimm M, Schneider F, Jedamzik P, Sager M, Kühn JP, Siegmund W, Weitschies W. Navigating the human gastrointestinal tract for oral drug delivery: Uncharted waters and new frontiers. Adv Drug Deliv Rev 2016; 101:75-88. [PMID: 27037063 DOI: 10.1016/j.addr.2016.03.009] [Citation(s) in RCA: 113] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2016] [Revised: 03/17/2016] [Accepted: 03/20/2016] [Indexed: 02/07/2023]
Abstract
Many concepts of oral drug delivery are based on our comprehension of human gastrointestinal physiology. Unfortunately, we tend to oversimplify the complex interplay between the various physiological factors in the human gut and, in particular, the dynamics of these transit conditions to which oral dosage forms are exposed. Recent advances in spatial and temporal resolution of medical instrumentation as well as improved access to these technologies have facilitated clinical trials to characterize the dynamic processes within the human gastrointestinal tract. These studies have shown that highly relevant parameters such as fluid volumes, dosage form movement, and pH values in the lumen of the upper GI tract are very dynamic. As a result of these new insights into the human gastrointestinal environment, some common concepts and ideas of oral drug delivery are no longer valid and have to be reviewed in order to ensure efficacy and safety of oral drug therapy.
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Abstract
The aim of this work was to develop a phosphate buffer based dissolution method for enteric-coated formulations with improved biopredictivity for fasted conditions. Two commercially available enteric-coated aspirin products were used as model formulations (Aspirin Protect 300 mg, and Walgreens Aspirin 325 mg). The disintegration performance of these products in a physiological 8 mM pH 6.5 bicarbonate buffer (representing the conditions in the proximal small intestine) was used as a standard to optimize the employed phosphate buffer molarity. To account for the fact that a pH and buffer molarity gradient exists along the small intestine, the introduction of such a gradient was proposed for products with prolonged lag times (when it leads to a release lower than 75% in the first hour post acid stage) in the proposed buffer. This would allow the method also to predict the performance of later-disintegrating products. Dissolution performance using the accordingly developed method was compared to that observed when using two well-established dissolution methods: the United States Pharmacopeia (USP) method and blank fasted state simulated intestinal fluid (FaSSIF). The resulting dissolution profiles were convoluted using GastroPlus software to obtain predicted pharmacokinetic profiles. A pharmacokinetic study on healthy human volunteers was performed to evaluate the predictions made by the different dissolution setups. The novel method provided the best prediction, by a relatively wide margin, for the difference between the lag times of the two tested formulations, indicating its being able to predict the post gastric emptying onset of drug release with reasonable accuracy. Both the new and the blank FaSSIF methods showed potential for establishing in vitro-in vivo correlation (IVIVC) concerning the prediction of Cmax and AUC0-24 (prediction errors not more than 20%). However, these predictions are strongly affected by the highly variable first pass metabolism necessitating the evaluation of an absorption rate metric that is more independent of the first-pass effect. The Cmax/AUC0-24 ratio was selected for this purpose. Regarding this metric's predictions, the new method provided very good prediction of the two products' performances relative to each other (only 1.05% prediction error in this regard), while its predictions for the individual products' values in absolute terms were borderline, narrowly missing the regulatory 20% prediction error limits (21.51% for Aspirin Protect and 22.58% for Walgreens Aspirin). The blank FaSSIF-based method provided good Cmax/AUC0-24 ratio prediction, in absolute terms, for Aspirin Protect (9.05% prediction error), but its prediction for Walgreens Aspirin (33.97% prediction error) was overwhelmingly poor. Thus it gave practically the same average but much higher maximum prediction errors compared to the new method, and it was strongly overdiscriminating as for predicting their performances relative to one another. The USP method, despite not being overdiscriminating, provided poor predictions of the individual products' Cmax/AUC0-24 ratios. This indicates that, overall, the new method is of improved biopredictivity compared to established methods.
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Affiliation(s)
- J Al-Gousous
- Institute of Pharmacy and Biochemistry, Johannes Gutenberg University Mainz , Staudinger Weg 5, 55099 Mainz, Germany
| | - G L Amidon
- Department of Pharmaceutical Sciences, University of Michigan , Ann Arbor, Michigan 48109, United States
| | - P Langguth
- Institute of Pharmacy and Biochemistry, Johannes Gutenberg University Mainz , Staudinger Weg 5, 55099 Mainz, Germany
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Hamed R, Awadallah A, Sunoqrot S, Tarawneh O, Nazzal S, AlBaraghthi T, Al Sayyad J, Abbas A. pH-Dependent Solubility and Dissolution Behavior of Carvedilol--Case Example of a Weakly Basic BCS Class II Drug. AAPS PharmSciTech 2016. [PMID: 26202065 DOI: 10.1208/s12249-015-0365-2] [Citation(s) in RCA: 97] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
The objective of this study was to investigate the pH-dependent solubility and dissolution of weakly basic Biopharmaceutical Classification Systems (BCS) class II drugs, characterized by low solubility and high permeability, using carvedilol, a weak base with a pK a value of 7.8, as a model drug. A series of solubility and in vitro dissolution studies was carried out using media that simulate the gastric and intestinal fluids and cover the physiological pH range of the GI from 1.2 to 7.8. The effect of ionic strength, buffer capacity, and buffer species of the dissolution media on the solubility and dissolution behavior of carvedilol was also investigated. The study revealed that carvedilol exhibited a typical weak base pH-dependent solubility profile with a high solubility at low pH (545.1-2591.4 μg/mL within the pH range 1.2-5.0) and low solubility at high pH (5.8-51.9 μg/mL within the pH range 6.5-7.8). The dissolution behavior of carvedilol was consistent with the solubility results, where carvedilol release was complete (95.8-98.2% released within 60 min) in media simulating the gastric fluid (pH 1.2-5.0) and relatively low (15.9-86.2% released within 240 min) in media simulating the intestinal fluid (pH 6.5-7.8). It was found that the buffer species of the dissolution media may influence the solubility and consequently the percentage of carvedilol released by forming carvedilol salts of varying solubilities. Carvedilol solubility and dissolution decreased with increasing ionic strength, while lowering the buffer capacity resulted in a decrease in carvedilol solubility and dissolution rate.
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40
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Shibata H, Yoshida H, Izutsu KI, Goda Y. Use of bicarbonate buffer systems for dissolution characterization of enteric-coated proton pump inhibitor tablets. ACTA ACUST UNITED AC 2016; 68:467-74. [PMID: 27019275 DOI: 10.1111/jphp.12540] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2015] [Accepted: 01/30/2016] [Indexed: 12/25/2022]
Abstract
OBJECTIVES The aim of this study was to assess the effects of buffer systems (bicarbonate or phosphate at different concentrations) on the in vitro dissolution profiles of commercially available enteric-coated tablets. METHODS In vitro dissolution tests were conducted using an USP apparatus II on 12 enteric-coated omeprazole and rabeprazole tablets, including innovator and generic formulations in phosphate buffers, bicarbonate buffers and a media modified Hanks (mHanks) buffer. KEY FINDINGS Both omeprazole and rabeprazole tablets showed similar dissolution profiles among products in the compendial phosphate buffer system. However, there were large differences between products in dissolution lag time in mHanks buffer and bicarbonate buffers. All formulations showed longer dissolution lag times at lower concentrations of bicarbonate or phosphate buffers. The dissolution rank order of each formulation differed between mHanks buffer and bicarbonate buffers. A rabeprazole formulation coated with a methacrylic acid copolymer showed the shortest lag time in the high concentration bicarbonate buffer, suggesting varied responses depending on the coating layer and buffer components. CONCLUSION Use of multiple dissolution media during in vitro testing, including high concentration bicarbonate buffer, would contribute to the efficient design of enteric-coated drug formulations.
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Affiliation(s)
- Hiroko Shibata
- National Institute of Health Sciences, Setagaya-ku, Tokyo, Japan
| | - Hiroyuki Yoshida
- National Institute of Health Sciences, Setagaya-ku, Tokyo, Japan
| | - Ken-Ichi Izutsu
- National Institute of Health Sciences, Setagaya-ku, Tokyo, Japan
| | - Yukihiro Goda
- National Institute of Health Sciences, Setagaya-ku, Tokyo, Japan
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41
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Wulff R, Rappen GM, Koziolek M, Garbacz G, Leopold C. Controlled release of acidic drugs in compendial and physiological hydrogen carbonate buffer from polymer blend-coated oral solid dosage forms. Eur J Pharm Sci 2015; 77:246-53. [DOI: 10.1016/j.ejps.2015.06.015] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2015] [Revised: 06/10/2015] [Accepted: 06/16/2015] [Indexed: 01/16/2023]
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González-García I, Mangas-Sanjuán V, Merino-Sanjuán M, Bermejo M. In vitro–in vivocorrelations: general concepts, methodologies and regulatory applications. Drug Dev Ind Pharm 2015; 41:1935-47. [DOI: 10.3109/03639045.2015.1054833] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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43
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In-vitro simulation of luminal conditions for evaluation of performance of oral drug products: Choosing the appropriate test media. Eur J Pharm Biopharm 2015; 93:173-82. [DOI: 10.1016/j.ejpb.2015.03.009] [Citation(s) in RCA: 128] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2015] [Revised: 03/03/2015] [Accepted: 03/05/2015] [Indexed: 11/21/2022]
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Krieg BJ, Taghavi SM, Amidon GL, Amidon GE. In Vivo Predictive Dissolution: Comparing the Effect of Bicarbonate and Phosphate Buffer on the Dissolution of Weak Acids and Weak Bases. J Pharm Sci 2015; 104:2894-904. [PMID: 25980464 DOI: 10.1002/jps.24460] [Citation(s) in RCA: 56] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2014] [Revised: 03/29/2015] [Accepted: 04/01/2015] [Indexed: 01/16/2023]
Abstract
Bicarbonate is the main buffer in the small intestine and it is well known that buffer properties such as pKa can affect the dissolution rate of ionizable drugs. However, bicarbonate buffer is complicated to work with experimentally. Finding a suitable substitute for bicarbonate buffer may provide a way to perform more physiologically relevant dissolution tests. The dissolution of weak acid and weak base drugs was conducted in bicarbonate and phosphate buffer using rotating disk dissolution methodology. Experimental results were compared with the predicted results using the film model approach of (Mooney K, Mintun M, Himmelstein K, Stella V. 1981. J Pharm Sci 70(1):22-32) based on equilibrium assumptions as well as a model accounting for the slow hydration reaction, CO2 + H2 O → H2 CO3 . Assuming carbonic acid is irreversible in the dehydration direction: CO2 + H2 O ← H2 CO3 , the transport analysis can accurately predict rotating disk dissolution of weak acid and weak base drugs in bicarbonate buffer. The predictions show that matching the dissolution of weak acid and weak base drugs in phosphate and bicarbonate buffer is possible. The phosphate buffer concentration necessary to match physiologically relevant bicarbonate buffer [e.g., 10.5 mM (HCO3 (-) ), pH = 6.5] is typically in the range of 1-25 mM and is very dependent upon drug solubility and pKa .
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Affiliation(s)
- Brian J Krieg
- College of Pharmacy, University of Michigan, Ann Arbor, Michigan, 48109
| | - Seyed Mohammad Taghavi
- Department of Chemical Engineering, Laval University, Quebec, Quebec City, G1V 0A6, Canada
| | - Gordon L Amidon
- College of Pharmacy, University of Michigan, Ann Arbor, Michigan, 48109
| | - Gregory E Amidon
- College of Pharmacy, University of Michigan, Ann Arbor, Michigan, 48109
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45
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Liu F, Shokrollahi H. In vitro dissolution of proton-pump inhibitor products intended for paediatric and geriatric use in physiological bicarbonate buffer. Int J Pharm 2015; 485:152-9. [DOI: 10.1016/j.ijpharm.2015.03.008] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2014] [Revised: 03/02/2015] [Accepted: 03/04/2015] [Indexed: 12/24/2022]
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46
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Garbacz G, Rappen GM, Koziolek M, Weitschies W. Dissolution of mesalazine modified release tablets under standard and bio-relevant test conditions. ACTA ACUST UNITED AC 2014; 67:199-208. [PMID: 25557626 DOI: 10.1111/jphp.12332] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2014] [Accepted: 09/09/2014] [Indexed: 01/28/2023]
Abstract
OBJECTIVES For the treatment of inflammatory bowel disease, the development of pH responsive modified release dosage forms is one of the most common approaches to achieve targeted drug delivery. In this study, the dissolution behaviour of eight different modified release (MR) products containing 800 mg mesalazine was investigated. METHODS The performance of the products was compared under simulated fasted state conditions using the paddle apparatus as well as the dissolution stress test device mimicking mechanical stress events of bio-relevant intensity. KEY FINDINGS The dissolution behaviour of the eight tested different pH-responsive MR tablets containing 800 mg mesalazine was dependent on the test conditions. Phases of mechanical stress with physiological intensity influenced the dissolution characteristics and caused in some cases accelerated drug release indicating possible dose dumping. CONCLUSION The study demonstrates that besides the investigation of the pH dependency of drug release, the characterisation of the mechanical robustness of the dosage forms is an essential factor determining the dissolution characteristics of such pH-dependent targeted modified release tablets. The susceptibility of 800 mg mesalazine MR tablets towards mechanical stress may be one reason for undesired drug delivery in vivo.
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Wulff R, Leopold C. Coatings from blends of Eudragit® RL and L55: A novel approach in pH-controlled drug release. Int J Pharm 2014; 476:78-87. [DOI: 10.1016/j.ijpharm.2014.09.023] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2014] [Revised: 09/11/2014] [Accepted: 09/12/2014] [Indexed: 10/24/2022]
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Koziolek M, Grimm M, Becker D, Iordanov V, Zou H, Shimizu J, Wanke C, Garbacz G, Weitschies W. Investigation of pH and Temperature Profiles in the GI Tract of Fasted Human Subjects Using the Intellicap(®) System. J Pharm Sci 2014; 104:2855-63. [PMID: 25411065 DOI: 10.1002/jps.24274] [Citation(s) in RCA: 273] [Impact Index Per Article: 27.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2014] [Revised: 10/29/2014] [Accepted: 10/29/2014] [Indexed: 12/20/2022]
Abstract
Gastrointestinal (GI) pH and temperature profiles under fasted-state conditions were investigated in two studies with each 10 healthy human subjects using the IntelliCap(®) system. This telemetric drug delivery device enabled the determination of gastric emptying time, small bowel transit time, and colon arrival time by significant pH and temperature changes. The study results revealed high variability of GI pH and transit times. The gastric transit of IntelliCap(®) was characterized by high fluctuations of the pH with mean values ranging from pH 1.7 to pH 4.7. Gastric emptying was observed after 7-202 min (median: 30 min). During small bowel transit, which had a duration of 67-532 min (median: 247 min), pH values increased slightly from pH 5.9-6.3 in proximal parts to pH 7.4-7.8 in distal parts. Colonic pH conditions were characterized by values fluctuating mainly between pH 5 and pH 8. The pH profiles and transit times described in this work are highly relevant for the comprehension of drug delivery of solid oral dosage forms comprising ionizable drugs and excipients with pH-dependent solubility.
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Affiliation(s)
- Mirko Koziolek
- Department of Biopharmaceutics and Pharmaceutical Technology, Center of Drug Absorption and Transport (C_DAT), Ernst Moritz Arndt University of Greifswald, Greifswald, D-17487, Germany
| | - Michael Grimm
- Department of Biopharmaceutics and Pharmaceutical Technology, Center of Drug Absorption and Transport (C_DAT), Ernst Moritz Arndt University of Greifswald, Greifswald, D-17487, Germany
| | - Dieter Becker
- Vivo Drug Delivery GmbH, Wollerau, CH-8832, Switzerland
| | - Ventzeslav Iordanov
- Medimetrics Personalized Drug Delivery B.V, NL, 5656, AE Eindhoven, The Netherlands
| | - Hans Zou
- Medimetrics Personalized Drug Delivery Inc., Briarcliff Manor, New York, 10510-2059
| | - Jeff Shimizu
- Medimetrics Personalized Drug Delivery Inc., Briarcliff Manor, New York, 10510-2059
| | - Christoph Wanke
- Medimetrics Personalized Drug Delivery B.V, NL, 5656, AE Eindhoven, The Netherlands
| | | | - Werner Weitschies
- Department of Biopharmaceutics and Pharmaceutical Technology, Center of Drug Absorption and Transport (C_DAT), Ernst Moritz Arndt University of Greifswald, Greifswald, D-17487, Germany
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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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Drechsler M, Garbacz G, Thomann R, Schubert R. Development and evaluation of chitosan and chitosan/Kollicoat® Smartseal 30 D film-coated tablets for colon targeting. Eur J Pharm Biopharm 2014; 88:807-15. [DOI: 10.1016/j.ejpb.2014.09.006] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2014] [Revised: 08/19/2014] [Accepted: 09/18/2014] [Indexed: 10/24/2022]
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