The MDI delivery system represents about 85 % of the relevant drug application in the EU and about 90 % worldwide. The main barriers for alternative delivery systems like dry powder inhalers (DPIs) are cost and usability (acceptance by patients). Typically the cost for a DPI is 2 1/2 fold compared to the cost for the corresponding MDI.
It is expected that by 2005 all drugs delivered by MDIs today will be available with HFC propellant in the EU. This ongoing transition from CFCs (chlorofluorocarbons) to HFCs (hydrofluorocarbons) as MDI propellants will reduce the global warming impact of MDI emissions by at least 75 % from 2000 to 2010.
In a business-as-usual scenario MDI emissions in the EU in 2010 are predicted to 5 to 6 Mtonnes CO2 equivalents corresponding to 0.13 % of total emissions, compared to a contribution of 1 % in 1995.