Stabilized Extracellular Vesicle Formulations for Inhalable Dry Powder Development

Area of Science:

• Biotechnology
• Regenerative Medicine
• Pulmonary Medicine

Background:

• Chronic obstructive pulmonary disease (COPD) is a major global health challenge, particularly impacting low- and middle-income countries.
• Extracellular vesicles (EVs) show promise for COPD treatment but require ultra-low temperature storage (-80°C), limiting accessibility.
• Developing accessible EV-based therapies is crucial for global health equity.

Purpose of the Study:

• To investigate alternative storage methods for extracellular vesicles (EVs) to enhance stability and accessibility.
• To evaluate the efficacy of inulin and mannitol as stabilizers for EVs.
• To develop a practical, inhalable EV formulation for COPD treatment.

Main Methods:

• EVs from lung fibroblasts were subjected to freezing, freeze-drying, and spray-drying with inulin or mannitol.
• Biophysical properties and functionality were assessed using lung organoid formation assays.
• Stability was evaluated after storage at various temperatures and humidity levels.
• Inhalable powder formulation and lung deposition were tested.

Main Results:

• Inulin effectively stabilized EVs, preserving functionality after freezing at -20°C for 12 weeks.
• Freeze-drying EVs with inulin maintained stability at 20°C and 43% relative humidity.
• Spray-dried EVs with inulin and leucine formed a stable, inhalable powder with good lung deposition.
• Mannitol led to EV aggregation and reduced bio-functionality.

Conclusions:

• Inulin is a promising stabilizer for extracellular vesicles (EVs), enabling ambient temperature storage.
• This approach eliminates the need for ultra-low temperature storage, significantly improving the accessibility of EV therapies.
• Inulin-based inhalable EV powders offer a practical and effective new treatment strategy for COPD.