Engineering multi-component delivery systems for the transcellular transport of inhalation therapeutics

The aim of the proposed project is to investigate the formulation behaviour and control the deposition of active pharmaceutical ingredient (API) multiplets to facilitate their interaction with in vitro respiratory epithelial cell layers. The controlled delivery of API particles to epithelial cell layers will enable investigation of the influence of co-deposition on the rates of API transepithelial transport, and ultimately API bioavailability. This project is funded by Pfizer Global Research and a BBSRC Doctoral Training CASE Award at King's College London

Many patients with asthma and chronic obstructive pulmonary disease are treated with multiple drug agents, and it is desirable to include two or more drug types in one inhaler product (a combination product). However the effects on the aerosol formed of one drug type when a second type of drug particle is difficult to predict. The potential different biological response of presenting two particles together on the cells or separately also require investigation.

We have developed a new analytical method to investigate the agglomerate formation of micronized particles

We have shown that adding a second drug particle changes the emission, powder entrainement and deagglomeration of micronized powders, in a similar manner to the use of excipient fines.

We have shown that agglomates of drug are likely to deposit in patients' lungs from dry powder inhalers.

We have shown that the size of these agglomerates is determined by the bulk and surface disorder of the particles.