Formulation of inhaled medicines

Description

Different types of dosage forms are used to deliver drugs to the lung and among these, inhalations powders are common due to their patient friendly properties. In order for particles to be inhalable and to be deposited in the lung, they have to be very fine with an aerodynamic particle diameter typically below 5 µm, resulting in a highly cohesive powder that is difficult to handle. The most common means to impart adequate powder properties is to use carrier-based formulations (adhesive mixtures), in which fine drug particles are adhered to the surface of considerably larger carrier particles.

In the research group, physical and formulation properties of such adhesive mixtures are studied. A classification system, denoted a blend state theory, has for example been introduced. With this conceptual description as starting position work is on-going how the blend state can be controlled as well as the possibility to affect the interparticulate forces acting in the blend. Carrier-free formulations, comprising loose agglomerates of fines, have gained increased popularity, especially for biopharmaceutical drugs and drugs that require high doses such as certain antibiotics.

Work in the group currently uses spray drying to prepare inhalation powders, and our aim is to improve the stability and performance of inhalation powders comprising biologics.