Multi-nozzle spray dryer, method for scale-up of spray dried inhalation powders, multi-nozzle apparatus and use of multiple nozzles in a spray dryer

Abstract

This present invention provides a spray dryer for use in preparing particles for inhalation, the spray dryer comprising a multi-nozzle apparatus comprising multiple single nozzles suitable for use in preparing inhalation powders and with a drying gas flow rate greater than about 80 kg/h. Also provided is a method for scaling-up a spray drying process for preparing particles for inhalation from a smaller scale spray dryer to a larger scale spray dryer, relative in size to each other, the method comprising the use in the larger scale spray dryer of a multi-nozzle apparatus comprising single nozzles suitable for use in preparing inhalation powders, wherein the number of nozzles in the larger spray dryer is determined by the ratio of the drying gas flow rate of the larger scale spray dryer to the drying gas flow rate of the smaller scale spray dryer. Also provided is a multi-nozzle apparatus produced from the method of the present invention, the multi-nozzle apparatus comprising multiple single nozzles suitable for use in preparing inhalation powders. Also provided is the use of multiple single nozzles suitable for use in preparing inhalation powders in a spray dryer with a drying gas flow rate greater than about 80 kg/h. The nozzles used in the present invention preferably prepare particles with a mean particle size less than about 5 microns.