Non-CFC metered dose inhalers: the patent landscape.

There have been many patent applications to the European Patent Office over the past decade involving the transition of pressurised metered dose inhalers from the CFCs to non-CFC propellants. In addition to those where formulations are changed, there are those relating to specific drugs or drug classes, processes of manufacture and modifications to the container/closure system. Many of these have been opposed, usually on the grounds of obviousness. However, due to the length of time for the opposition process and the fact that there are few non-CFC pressurised inhalers on the market yet, the complete picture of which patents are valid has yet to unfold.