The invention provides lipid-based dispersion comprising comprising, a) phosphatidyl choline; b) an anionic phospholipid; optionally c) up to 1% cholesterol by weight of total lipids; and optionally d) a therapeutic agent; wherein the mean particle size measured by dynamic light scattering is less than 100 nm. The invention also provides pharmaceutical compositions comprising such a dispersion as well as methods of producing a therapeutic effect in a mammal comprising administering an effective amount of such a dispersion.
