here. You have a lot of data in the material that's in your background packages. I will try to address each of the issues that the agency and Wally in his presentation here have raised, and as he indicated, some of the answers to those issues have been recently provided to the agency in a package that I do not think that you have received yet. At the end of this presentation, I do hope that the advisory committee will agree that the PTI test is a step forward.
As we heard Wally tell you, the DDU is one of several quality attributes that is tested for OINDPs, and importantly, this one combines the performance of the delivery device and the formulation which makes it a more complex thing, and DDU is there to verify delivered-dose uniformity in the batch, between containers and within containers for a multi-dose product, and, of course, closeness to the target.
So there are many types of oral inhalation and nasal drug products: pressurized metered-dose inhalers, dry powder inhalers, nasal sprays, inhalation solutions. All of them are intended to deliver a dose of aerosol to the respiratory tract to treat different diseases.