Modulite: a simple solution to a difficult problem.

The development of HFA-based pMDIs has proved difficult due to differences in the physico-chemical properties of CFC and HFA propellants. However, the development of solution formulations instead of suspensions has provided a way to formulate products whose cloud characteristics can be modulated in a controlled manner by permitting different formulation and device hardware variables. The new approach has proved successful in formulating several different drugs including steroids and has now been applied to developing a formoterol Modulite solution formulation characterized by good chemical stability, delivery performance, and clinical results.