Human lung deposition data: the bridge between in vitro and clinical evaluations for inhaled drug products?

Regulatory dossiers for new inhaled drug products generally contain in vitr o data, which assess delivered dose and particle size distribution, togethe r with clinical efficacy and safety data. Human lung deposition data may be generated using radionuclide imaging techniques or appropriate pharmacokin etic methods, and can act as a 'bridge' via which a seamless transition can be made between in vitro testing in the laboratory and efficacy/safety tes ting in the clinic. By enabling informed decisions to be made about the eva luation of new devices or formulations in man, lung deposition data permit a long and expensive clinical trials programme to be commenced with much gr eater certainty of a successful outcome. Human lung deposition data should be considered for supplementing the information required For regulatory dos siers. (C) 2000 Elsevier Science B.V. All rights reserved.