As a nasal drug delivery company, Kurve's goal is to get close to 100% of the drug into the nasal cavity and onto the nasal mucosa. To accomplish this, ViaNase delivers droplets ≥8 μm in order to avoid pulmonary deposition. In fact, ViaNase is capable of generating narrow droplet distributions from 3-50 μm. However, for optimal nasal drug delivery device, Kurve uses a size range between 10 and 30 μm.
The upper limit of 30 μm was determined because larger droplets are more difficult to control in vortical flow and deposition is reduced. CPD's ability to generate a range of droplets in tight distribution curves allows for small incremental changes in the mass median aerodynamic diameter (MMAD), so slight adjustments can be made to optimise performance of a particular formulation.
In early tests, droplet sizes of 15-20 μm consistently performed well across many compounds. CPD produces a droplet distribution curve with droplets at a Dv10 of 9 μm, a Dv50 of 19 μm and a Dv90 of 29 μm. This distribution not only leaves all of the droplets within a controllable range, but virtually eliminates peripheral deposition in the stomach and lungs.
Figure 2 compares droplet sizes from CPD, nebulizers, and spray bottles.