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Development of Predictive Tools for Amorphous Solid Dosage Forms

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Development of Predictive Tools for Amorphous Solid Dosage Forms __________________________________________________________ Development of predictive tools for amorphous solid dosage forms Dissertation zur Erlangung des Grades „Doktor der Naturwissenschaften” im Promotionsfach Pharmazie am Fachbereich Chemie, Pharmazie und Geowissenschaften Institut für Pharmazie und Biochemie Abteilung Biopharmazie und Pharmazeutische Technologie der Johannes Gutenberg Universität Mainz Matthias Manne Knopp geboren in Glostrup, Dänemark Mainz, 2016 D77 – Mainzer Dissertation Dekan: Univ.-Prof. Dr. Dirk Schneider 1. Berichterstatter: 2. Berichterstatter: Tag der mündlichen Prüfung: 4. November 2016 “The value of an education is not learning facts, but training the mind to think something that cannot be learned from textbooks” – Albert Einstein Acknowledgements i Abbreviations list ANOVA Analysis of variance AUC Area under the curve BCS Biopharmaceutics classification system BDDCS Biopharmaceutics drug disposition classification system Cmax Maximum concentration CAP Chloramphenicol CCX Celecoxib COX Cyclooxygenase Cp Heat capacity DCS Developability classification system DSC Differential scanning calorimetry EDTA Ethylenediaminetetraacetic acid FaSSIF Fasted state simulated intestinal fluid FeSSIF Fed state simulated intestinal fluid FDA Food and Drug Administration (USA) FDP Felodipine FTIR Fourier transform infrared Hm Melting enthalpy (enthalpy of fusion) HPC Hydroxypropyl cellulose HPLC High-performance liquid chromatography HPMC Hydroxypropyl methylcellulose HPMCAS Hydroxypropyl methylcellulose acetate succinate IMC Indomethacin IVIVC In vitro–in vivo correlation LOD Limit of detection Log P Partition coefficient LOQ Limit of quantification MV Molecular volume ii Mw Molecular weight NSAID Nonsteroidal anti-inflammatory drug NVP N-vinylpyrrolidone PAA Polyacrylic acid PCM Paracetamol (acetaminophen) PEG Polyethylene glycol PVP Polyvinylpyrrolidone PVP/VA Polyvinylpyrrolidone/vinyl acetate copolymer PVA Polyvinyl acetate PTFE Polytetrafluoroethylene (Teflon) r2 Coefficient of determination RSD Relative standard deviation SD Standard deviation SEDDS Self-emulsifying drug delivery system SEM Standard error of the mean SOL Soluplus® (polyvinyl caprolactam – PVA – PEG graft copolymer) SSR Sum of squared residuals Ta Annealing temperature Tc Crystallization temperature Tend Melting temperature (end point) Tg Glass transition temperature Tm Melting temperature (onset) tmax Time to reach maximum concentration (Cmax) USP United States Pharmacopoeia UV Ultraviolet VA Vinyl acetate VP Vinylpyrrolidone XRPD X-ray powder diffraction iii Table of contents Acknowledgements .......................................................................................................................... i Abbreviations list ............................................................................................................................ ii Background ..................................................................................................................................... 1 1. Poorly water-soluble drugs ......................................................................................................... 2 1.1 Classification and definitions ................................................................................................ 3 1.2 Model compounds ................................................................................................................. 4 2. Amorphous solid dispersions ...................................................................................................... 6 2.1 Thermodynamics of amorphous materials ............................................................................ 6 2.2 Classification and definitions ................................................................................................ 8 2.3 Historical overview ............................................................................................................. 10 2.4 Methods of preparation ....................................................................................................... 13 2.4.1 Melting/fusion .............................................................................................................. 14 2.4.2 Solvent evaporation ...................................................................................................... 14 2.4.3 Co-precipitation ............................................................................................................ 16 2.4.4 Mechanical force .......................................................................................................... 16 3. Development considerations ..................................................................................................... 18 3.1 Methods to predict maximum drug–polymer ratio ............................................................. 20 3.1.1 Melting point depression method ................................................................................. 24 3.1.2 Liquid analogue solubility method ............................................................................... 25 3.1.3 Dissolution method ....................................................................................................... 26 3.1.4 Recrystallization method .............................................................................................. 27 3.1.5 Zero enthalpy extrapolation method ............................................................................. 30 3.2 Assessing in vitro supersaturation behavior ........................................................................ 31 Aims of the dissertation ................................................................................................................ 34 4. Evaluation of drug–polymer solubility curves through formal statistical analysis: Comparison of preparation techniques .............................................................................................................. 35 4.1 Abstract ............................................................................................................................... 35 4.2 Introduction ......................................................................................................................... 35 4.3 Experimental ....................................................................................................................... 37 4.4 Results ................................................................................................................................. 39 4.5 Discussion ........................................................................................................................... 47 4.6 Conclusion ........................................................................................................................... 49 iv 5. Influence of polymer molecular weight on drug–polymer solubility: A comparison between experimentally determined solubility in PVP and prediction derived from solubility in monomer ....................................................................................................................................................... 51 5.1 Abstract ............................................................................................................................... 51 5.2 Introduction ......................................................................................................................... 51 5.3 Experimental section ........................................................................................................... 53 5.4 Theoretical considerations................................................................................................... 55 5.5 Results ................................................................................................................................. 56 5.6 Discussion ........................................................................................................................... 62 5.7 Conclusion ........................................................................................................................... 65 6. A comparative study of different methods for the prediction of drug–polymer solubility ....... 66 6.1 Abstract ............................................................................................................................... 66 6.2 Introduction ......................................................................................................................... 66 6.3 Experimental section ........................................................................................................... 68 6.4 Theoretical considerations................................................................................................... 72 6.5 Results and discussion ......................................................................................................... 76 6.6 Conclusions ......................................................................................................................... 87 7. Influence of PVP/VA copolymer composition on drug–polymer solubility ............................ 89 7.1 Abstract ............................................................................................................................... 89 7.2 Introduction ......................................................................................................................... 89 7.3 Experimental section ..........................................................................................................
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