LIPOSOME HAVING A MULTICOMPONENT BILAYER WHICH CONTAINS A BIOACTIVE AGENT AS AN INTEGRAL COMPONENT OF THE BILAYER

摘要

This invention provides a liposome having a multicomponent bilayer. This bilayer contains: a pocket-forming component which is an amphipathic lipid with asymmetric acyl chains, that is acyl chains of uneven length; a bilayer thickness component which is an amphipathic lipid with symmetric or asymmetric acyl chains, provided that any such asymmetry, or inequality of length, is less than or equal to the asymmetry of the acyl chains of the pocket-forming component; and a bioactive agent which is an integral component of the multicomponent bilayer. The multicomponent bilayer will, when necessary to inhibit phase separation of the pocket-forming and bilayer thickness components, also contain an amphipathic lipid known as a phase separation prevention component. The bioactive agent may be a therapeutic agent such as antibacterial, antifungal, antiviral and antiparasitic agents, and is likely to be an anticancer agent such as taxol, camptothecin or nogalamycin. Accordingly, pharmaceutical compositions containing the liposome of this invention may be administered to animals for the treatment or prevention of diseases such as antimicrobial infections and cancers.