In Vitro/In Vivo Correlations for Respiratory Drug Delivery

This is the authors' abstract. We don't add key points for this paper.

In vitro drug delivery data for pulmonary and nasal drug products have great importance, particularly for quality control and product release. However, in vitro tests which measure emitted dose and particle size distribution of both pulmonary and nasal aerosols, as well as the spray pattern and plume geometry of nasal sprays, do not take into account the interactions between the aerosol particles and the airways when inhalers are used by patients. While agreement between in vitro and in vivo data is sometimes good, in vitro data may not predict in vivo drug delivery adequately in some situations. In vivo tests of drug delivery, using either radionuclide imaging or appropriate pharmacokinetic methods, may be a useful adjunct to in vitro testing in early product development.