LIPID CARRIER COMPOSITIONS WITH REDUCED POLY-DISPERSITY
The invention relates to a method for reducing the polydispersity of a population of gel-phase lipid-based delivery vehicles.
1 . A method for reducing the polydispersity of a suspension of gel-phase lipid-based delivery vehicles which method comprises the step of extruding a suspension of said vehicles at a temperature below the phase transition temperature of said vehicles.
2 . The method of claim 1 , which further comprises, prior to said step, extruding said suspension at a temperature above the phase transition temperature of said vehicles.
3 . The method of claim 1 or 2 wherein the delivery vehicles are liposomes.
4 . The method of claim 3 wherein the liposomes comprise a membrane-rigidifying agent.
5 . The method of claim 4 wherein the membrane-rigidifying agent comprises cholesterol.
6 . The method of claim 3 wherein the liposomes comprise less than 25 mol % cholesterol.
7 . A composition of gel-phase lipid-based delivery vehicles prepared by the methods of any of claims 1 - 6 .
8 . A composition of gel-phase lipid-based delivery vehicles that is sufficiently size-controlled that a suspension of said vehicles can be effectively filter sterilized.
9 . The composition of claim 8 wherein the vehicles are liposomes.
10 . The composition of claim 9 wherein the liposomes comprise a membrane-rigidifying agent.
11 . The composition of claim 10 wherein the membrane-rigidifying agent comprises cholesterol.
12 . The composition of claim 9 wherein the liposomes comprise less than 25 mol % cholesterol.