Patent ID: 7229645
Filing Date: 2007-06-12
Classification: A61K,A61P

Abstract:
1. A process for the preparation of a powder for transdermal particle delivery via needleless injection, which process comprises the step of spray freeze-drying an aqueous solution or suspension via atomising the aqueous solution or suspension into a liquified gas followed by freeze-drying of the liquified gas containing the resulting frozen droplets of the aqueous solution or suspension, wherein said solution or suspension comprises a pharmaceutical agent, and has a solids content of 20% by weight or more, wherein alum is either absent or at a concentration of 30 mg/ml or less, wherein said pharmaceutical agent is selected from the group consisting of a peptide, a hormone, a nucleic acid, a gene construct, an antigen, an antibiotic, an anti-viral agent, an analgesic or analgesic combination, a local or general anaesthetic, and an anti-inflammatory, wherein the drying is conducted in the absence of an organic solvent, wherein said particles have a particle mass mean aerodynamic diameter (MMAD) of from 20 to 70 μm, a particle density of 0.7 to 1.5 g/cm wherein the individual particles of the powder have a substantially spherical aerodynamic shape with a substantially uniform, non-porous surface, have a particle penetration energy suitable for transdermal delivery from a needleless syringe device, and are free-flowing under a dry environment.