Solid state of inhalable high dose powders

High dose inhaled powders have received increased attention for treating lung infections. These powders can be prepared using techniques such as spray drying, spray-freeze drying, crystallization, and milling. The selected preparation technique is known to influence the solid state of the powders, which in turn can potentially modulate aerosolization and aerosolization stability.

Highlights

Preparation techniques play an important role in defining solid state of powders.

Amorphous powders exhibit both poor physical and chemical stability.

The impact of solid state on aerosolization of high dose powder is still unclear.

Aerosolization stability of amorphous powders can be improved via surface enrichment or co-amorphization with hydrophobic excipient/API.

Solid dispersions, mesoporous systems, or co-amorphous systems might be prepared to stabilize amorphous states.

This review focuses on how and to what extent the change in solid state of high dose powders can influence aerosolization. It also discusses the commonly used solid state characterization techniques and the application of potential strategies to improve the physical and chemical stability of the amorphous powders for high dose delivery.

Bishal Raj Adhikari, Keith C. Gordon, Shyamal C. Das, Solid state of inhalable high dose powders, Advanced Drug Delivery Reviews, Volume 189, 2022, 114468, ISSN 0169-409X,
https://doi.org/10.1016/j.addr.2022.114468.