Scale-Up of Liposome Manufacturing

The study provides a comprehensive overview on different
stabilization techniques for liposomal formulations. The selection
of the appropriate technology for a particular formulation can
thereby be based on several considerations. If free flowable
particulate bulk material is desired the spraying-technologies are
preferred over lyophilization. Another advantage of spraying-based
technologies is the possibility to combine the liposome formation
step and the drying step within the same process. It is a
prerequisite for the selection of the stabilization technique that
the integrity of the liposomes is preserved with the incorporated
drug after the process. Spray-drying is related to a thermal stress
for the formulation but only for a short time. For heat labile
drugs processes with low process temperatures, e.g. freeze-drying,
spray freeze-drying, inert-spray drying or supercritical drying are
most adequate. However, for technologies with a freezing step a
sufficient stabilization against freezing induced stress e.g. by
the selection of appropriate cryoprotectors is needed.