The present invention provides a manufacturing process for liposomal preparations comprising water-insoluble or hydrophobic active principals. In accordance with one aspect of the inventive method, at least one active principal and lipid fraction are dissolved in an organic solvent. This solution is then subjected to reduced pressure (vacuum) in a container with or with out inert packing to remove the organic solvent, thereby forming a puffy cake comprising the active principal or principals and lipid fraction. This puffy cake is then mixed with an aqueous solution, under controlled conditions suitable to form a bulk liposomal preparation. Because the active principal is imbedded in the lipid bilayer, removal of the aqueous solution is optional.
