Patent ID: 6436905
Filing Date: 2002-08-20
Classification: A61K,A61P

Abstract:
A lipid-containing composition having a visual appearance of a substantially clear solution comprising,a membrane-forming polar lipid dispersed in an aqueous medium together with a synthetic amphipathic polymer that interacts with the polar lipid to produce a polymer/lipid complex, whereby said polymer interacts with and solubilizes the polar lipid in the aqueous medium at a pH which is below a critical lipid-solubilizing value and at a temperature above a predetermined phase transition temperature dependant upon the polar lipid, such that said polymer/lipid complex is in the form of non-liposomal micellar particles or assemblies of discoidal form in which the polar lipid forms a bilayer core; said composition being pH variable, such that the pH can be raised from below the critical lipid-solubilizing value to above the critical lipid-solubilizing value by addition of alkaline reagent; said synthetic amphipathic polymer being a non-block copolymer having a linear backbone along which hydrophobic groups and anionic hydrophilic groups are evenly arranged, and comprising a first monomer which is an unsaturated dicarboxylic acid or anhydride thereof, and a second monomer which is a monoeneoic compound, said first and second monomers being arranged in alternating relationship along the linear backbone, with the proviso that, if the second monomer is an alkyl vinyl ether, the alkyl group thereof has from 2 to 8 carbon atoms, and, wherein the number of carbon atoms in the hydrophobic side groups of the amphipathic polymer is equal to or greater than the number of carbon atoms in the polymer backbone.