Designing nanoparticle-based inhaled antibiotics for the treatment of cystic fibrosis associated biofilms and infections and in vivo studies in a rat model.

• Applicants: Professorin Dr. Dagmar Fischer; Dr. Meike Müller; Professor Dr. Mathias W. Pletz
• Subject Area: Pharmacy ; Pneumology, Thoracic Surgery
• Term: from 2014 to 2020
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 256755002

• Final Report Year: 2020

Final Report Abstract

In the first funding period, we developed und optimized, by systematic variation of the formulation process, different micro- and nanoparticular formulations of polyester polymers in which different antibiotics with anti-pseudomonal activity were stably and efficiently encapsulated. Particles were extensively characterized regarding their physicochemical characteristics and storage forms were developed. In in vitro assays, we were able to demonstrate that non-encapsulated tobramycin exhibits no activity against biofilms of Pseudomonas aeruginosa and Burkholderia cepacia biofilms. In contrast, nanoparticle encapsulation restored the activity of tobramycin against these biofilms. The effectiveness of the PEG-PLGA-encapsulated tobramycin was 1000fold higher against the biofilms compared to the free drug or a blend of both components; thereby, the effective concentration of encapsulated tobramycin was even below concentrations measured during tobramycin i.v. treatment. Moreover, biofilms of B. cepacia, which is intrinsically resistant to tobramycin, could be efficiently eradicated. Both examples indicate an improved or even restored efficacy of the PEG-PLGA particles in vitro. In the second funding period, the in vitro results were transferred to a rodent model for lung infections to investigate the safety and efficacy of inhaled nanoparticle-encapsulated tobramycin in vivo. The aims were (i) the clarification of the underlying mechanism of the improved/restored efficacy of encapsulated tobramycin, (ii) the formulation of the micro- and nanoparticles applicable for inhalation and the confirmation of sufficient pulmonary deposit of the drug, (iii) the characterization of the safety profile in vivo, and (iv) the proof-of-concept of the superior efficacy of the inhaled tobramycin-encapsulated formulation compared to pure inhaled tobramycin.

Publications

• Aspects of pulmonary drug delivery strategies for infections in cystic fibrosis -- where do we stand? Expert opinion on drug delivery, 2015.12(8): 1351-1374
  M. Klinger-Strobel, C. Lautenschläger, D. Fischer, JG. Mainz, T. Bruns, L. Tuchscherr, M. W. Pletz and O. Makarewicz
  
• A blue fluorescent labeling technique utilizing micro-and nanoparticles for tracking in LIVE/DEAD stained pathogenic biofilms of Staphylococcus aureus and Burkholderia cepacia. International Journal of Nanomedicine, 2016. 11: 575
  M. Klinger-Strobel, J. Ernst, C. Lautenschläger, M. W. Pletz and D. Fischer, O. Makarewicz
  
• A Novel Computerized Cell Count Algorithm for Biofilm Analysis. PloS one, 2016. e0154937
  M. Klinger-Strobel, H. Suesse, D. Fischer, MW. Pletz, O. Makarewicz
  
• Bactericidal effect of a photoresponsive carbon monoxide releasing non-woven against Staphylococcus aureus biofilms. Antimicrobial agents and chemotherapy, 2016. AAC-00703
  M. Klinger-Strobel, S. Gläser, O. Makarewicz, R. Wyrwa, J. Weisser and M. W. Pletz, A. Schiller
  
• Chapter 2: Antibiotic resistance in respiratory infections: mechanisms and epidemiology, in ERS Monograph: Antiinfectives and the Lung. 2017
  O. Makarewicz, M. Klinger-Strobel, R. Ehricht, M. Kresken and M. W. Pletz
  
• Effects of colistin on biofilm matrices of Escherichia coli and Staphylococcus aureus. International Journal of Antimicrobial Agents, 2017. 49(4): 472-479
  M. Klinger-Strobel, C. Stein, C. Forstner, O. Makarewicz and M. W. Pletz
  
• In vitro synergism and anti-biofilm activity of ampicillin, gentamicin, ceftaroline and ceftriaxone against Enterococcus faecalis. Journal Antimicrobial Chemotherapy, 2018. 73(6): 1553-1561
  L. Thieme, M. Klinger-Strobel, A. Hartung, C. Stein, O. Makarewicz and M. W. Pletz
  
• Polyester-Based Particles to Overcome the Obstacles of Mucus and Biofilms in the Lung for Tobramycin Application under Static and Dynamic Fluidic Conditions. European Journal of Pharmaceutics Biopharmaceutics, 2018. 131: 120-129
  J. Ernst, M. Klinger-Strobel, K. Arnold, J. Thamm, A. Hartung, M. W. Pletz, O. Makarewicz and D. Fischer
  
• Breaking the Biofilm Barrier: The Role of Stabilizers in Biofilm Penetration and Pulmonary Antibiotic Delivery by Polymer Nanoparticles. Die Pharmazeutische Industrie, 2019. 81(2):248-255
  J. Ernst, M. Klinger-Strobel, J. Thamm, O. Makarewicz, M. W. Pletz and D. Fischer
  
• MBEC Versus MBIC: the Lack of Differentiation between Biofilm Reducing and Inhibitory Effects as a Current Problem in Biofilm Methodology. Biological Procedures Online, 2019. 21: 18
  L. Thieme, A. Hartung, K. Tramm, M. Klinger-Strobel, K. D. Jandt, O. Makarewicz and M. W. Pletz
  
• A shell-less hen’s egg test as infection model to determine the biocompatibility and antimicrobial efficacy of drugs and drug formulations against Pseudomonas aeruginosa. International Journal of Pharmaceutics, 2020. 585 (2020): 119557
  P. Warncke, S. Fink, C. Wiegand, U. C. Hipler and D. Fischer