Spray Dry Formulations
The levitated drop experiments outlined above are simulations of spray drying where the solvent evaporates from a droplet leaving a solid particle. Thus the translation from the levitated drop experiments to spray drying is expected to be routine in typical cases. Scale-up of manufacturing using spray drying is provided by Improved Pharma through its collaboration with the Purdue University Industrial Pharmacy Services Laboratory. The formulation is then hand filled into capsules for further study. If needed, GMP manufacturing can be provided in either the Purdue GMP Center or at the University of Minnesota GMP laboratory. In this way, formulations can be scaled up to prepare clinical supplies in a rapid, efficient manner.
A range of parameters needs to be controlled to optimize formulations prepared by spray drying. These parameters include solvent, polymer, polymer to drug ratio, salt formation, and the inclusion of surfactants. Typically, a design of experiments matrix is utilized to guide these experiments. Pair distribution function (PDF), stability, and/or dissolution profile are utilized to evaluate the various formulations. Improved pharma can provide a complete optimization study following these general procedures. The exact parameters optimized are determined on a case-by-case basis. Of particular interest is the utilization of salt-forming polymers to prepare especially stable formulations. Once the methods are optimized, they can be scaled up to prepare clinical supplies.