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CYCLODEXTRINS AS Excyclodextrins As Excipients in Drying of Proteins and Controlled Ice Nucleation in Freeze-Drying

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CYCLODEXTRINS AS Excyclodextrins As Excipients in Drying of Proteins and Controlled Ice Nucleation in Freeze-Drying Dissertation zur Erlangung des Doktorgrades der Fakultät für Chemie und Pharmazie der Ludwig-Maximilians-Universität München CYCLODEXTRINS AS EXCIPIENTS IN DRYING OF PROTEINS AND CONTROLLED ICE NUCLEATION IN FREEZE-DRYING Raimund Michael Geidobler Aus Rosenheim, Deutschland 2014 Erklärung Diese Dissertation wurde im Sinne von § 7 der Promotionsordnung vom 28. November 2011 von Herrn Prof. Dr. Gerhard Winter betreut. Eidesstattliche Versicherung Diese Dissertation wurde eigenständig und ohne unerlaubte Hilfe erarbeitet. München, den 03.03.2014 Raimund Michael Geidobler Dissertation eingereicht am: 28.01.2014 1. Gutachter: Prof. Dr. G. Winter 2. Gutachter: Prof. Dr. W. Frieß Mündliche Prüfung am: 27.02.2014 2 3 4 FOR MY PARENTS 5 Acknowledgements ACKNOWLEDGEMENTS Finally, after three and a half year, uncounted number of vials analyzed and buffers prepared, it is time to say thank you. First and foremost, I want to thank Prof. Dr. Gerhard Winter for accepting me into his research group and for his continuous guidance and encouragement throughout the years in which this thesis was created. Thanks also for creating a constructive atmosphere, for challenging tasks and questions and for providing a perfect workspace and an overall good atmosphere. I am most grateful for his idea to look into controlled ice nucleation, which, in my opinion, became a quite successful story. Under his supervision, I did not only improve as a scientist but I could learn a lot for my personal development. Special thanks go to Prof. Dr. Wolfgang Frieß, not only for being part of my thesis committee but also for his interest in my research work. Thanks also for sharing scientific expertise, especially the little tweaks for the spray drier. He is also responsible for the warm atmosphere in the research groups I was always happy to be part of. With Yibin Deng, I shared a nice atmosphere in our lab during the time we spent together. You did not only always participate in football together with me, but you broadened my mind by sharing the Chinese culture with me. I also like the time when we were skiing and you really impressed me with your fast advance in skiing and for completing a thesis without consuming coffee. Furthermore, I want to say thanks to all the nice people in both research groups, for also creating a nice atmosphere and for always finding a solution when problems occurred. It is difficult to mention someone in particular, but I am most grateful for all the (scientific) discussions with Thomas Bosch. Angelika Freitag, Sebastian Hertel, Markus Hofer, Elsa Etzl and Gerhard Sax, you gave me the feeling of being a part of the team from the first day on. Special thanks go to my students, who supported this work with a Bachelor’s thesis or internships, namely Sabrina Nesslinger, Stefanie Mannschedel, Elena Ilyukhina, Verena Seitz, Katharina Geh, Lucia Auchtor, Michaela Breitsamer and Martin Schubert. You all did a very good job, I really liked to work with you. Sarah Coultas from Kratos analytical, Christian Minke and Mona Calik from the LMU are kindly acknowledged for helping me with measurements of certain samples. When caring for science all the time, someone needs some balance off work. Here I want to say thanks to Cihad Anamur, who had to listen to all the roadbike-stuff I told him until finally, he bought his own bike. Since then, we have shared a lot of kilometres together. I am looking forward to even more! 6 Acknowledgements To all my friends from the studies of pharmacy also goes a warm thank you. Without you and the fun we had together, the time with exams and practical work would have been a lot less endurable. Thank you for becoming and still staying friends, Christian Behrens, Michael Hornburger, Anja Müller, Geoffrey Grünwald, Orhan Causevic, Peter Schweiberger, Florian Schmid, Maren Ketterle, Veronika Schmitt, Martin Bubik, Benjamin Schwenk and Christiane Pauli. I really appreciate the support from my friends from school, thank you Christoph Traunsteiner, Franz Angerer, Martin Höchstetter, Florian Wimmer and Mark Read. Of course I want to deeply thank my parents Maria and Raimund for supporting me through all the years until the first job. Without you, I even couldn’t have started this work. Hence, this thesis is devoted to you. Of course I want to thank my sister Carolin and my brother Maximilian. Finally, I want to say thanks to Verena for her support during the last phase of the thesis, for her love and patience and for having become such an important person in my life in the last year. 7 Table of contents TABLE OF CONTENTS I. Objectives of the thesis ...................................................................................................... 11 II. Cyclodextrins in freeze-drying and spray-drying of proteins ......................................... 13 II.1 Introduction .......................................................................................................................... 13 II.1.1 General mechanisms of stabilization by excipients during freezing, drying and in the dried state ........................................................................................................................................... 13 II.1.2 Possible mechanisms of stabilization provided by cyclodextrins ...................................... 14 II.1.3 Tabular overview of cyclodextrins used as excipients for drying of proteins .................... 15 II.1.4 Protein stabilization by cyclodextrins at low CD-concentrations – non-ionic surfactant-like behaviour ....................................................................................................................................... 18 II.1.5 Protein stabilization by cyclodextrins used at high concentrations – water replacement and vitrification ...................................................................................................................................... 20 II.1.6 Protein stabilization by cyclodextrins during storage of lyophilizates ................................ 21 II.1.7 Conclusions ....................................................................................................................... 22 II.1.8 Rational use Of cyclodextrins in parenteral protein formulations ...................................... 22 II.1.9 Aim of the study ................................................................................................................. 24 II.2 Material and methods .......................................................................................................... 25 II.2.1 Materials ............................................................................................................................ 25 II.2.2 Preparation of formulations ............................................................................................... 25 II.2.3 Lyophilization processes ................................................................................................... 25 II.2.4 Sample preparation for freeze-thaw studies ...................................................................... 26 II.2.5 Spray-drying process ......................................................................................................... 26 II.2.6 Preparation of atomization-control samples ...................................................................... 27 II.2.7 Reconstitution of dried products ........................................................................................ 27 II.2.8 Turbidity ............................................................................................................................. 27 II.2.9 Light obscuration ............................................................................................................... 27 II.2.10 Size exclusion chromatography (SE-HPLC) ................................................................. 28 II.2.11 Asymmetrical flow-field-flow separation (AF4) .............................................................. 28 II.2.12 Fourier-transform infrared spectroscopy (FTIR) ............................................................ 29 II.2.13 Residual moisture content (headspace method) ........................................................... 29 II.2.14 Residual moisture content (direct injection method) ..................................................... 29 II.2.15 Dynamic scanning calorimetry (T g’) ............................................................................... 29 II.2.16 Dynamic scanning calorimetry (T g) ................................................................................ 30 II.2.17 Specific surface area ..................................................................................................... 30 II.2.18 X-ray powder diffraction ................................................................................................. 30 II.2.19 Electron spectroscopy for chemical analysis (ESCA) ................................................... 31 II.3 Results .................................................................................................................................. 32 II.3.1 Cyclodextrins as replacement for polysorbates - Formulation development for the model protein MabR1 ............................................................................................................................... 32 II.3.2 Further screening of formulations for the model protein MabR1 ....................................... 41 II.3.3 Collapse freeze-drying of MabR1 .....................................................................................
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