Particle Deposition in Respiratory Tract: Where are the Limits?

Abstract

In last two decades in silico biopharmaceutics modelling has become increasingly important in all stages of drug development. One of the widely used pharmacokinetic modelling software is Gastro Plus that, with its additional dosage routes modules, enables creation of pharmacokinetic models, amongst others, for pulmonary dosage route. Medicines that are applied via that route have specific methods for characterization and analysis. However, drug that is target of in silico method in Gastro Plus is not characterized in full extent with such parameters. In this work we created various models of size distributions and depositions of two pMDI preparations containing beclomethasone dipropionate in 4 respiratory compartments of Gastro Plus Pulmonary model. Those data were compared with results of in vivo studies and model with best correlation was obtained. Such model with defined cut-off limits between each compartment enables better prediction of pharmacokinetic properties in generated Gastro Plus in silico model.