Sustained-release pharmaceutical compositions comprising of a sedative drug and uses thereof

A pharmaceutical composition, comprising

• (a) a first liposome comprising a bilayer membrane, said bilayer membrane comprises a mixture of a first lipid that is hydrogenated soy phosphatidylcholine (HSPC), 1,2-distearoyl-sn-glycero-3-phosphocholine (DSPC) or any combination thereof, cholesterol, and optionally a second lipid that is a phosphatidylethanolamine (PE), a phosphatidylglycerol (PG) or any combination thereof, wherein the mole percent of the first lipid is between 45-80%, the mole percent of cholesterol is 20-55% and the mole percent of the second lipid is 0.1-25%;
• (b) a trapping agent selected from the group consisting of triethylammonium sucrose octasulfate, ammonium sulfate, ammonium phosphate, dextran sulfate and any combination thereof;
• and
• (c) a sedative drug that is dexmedetomidine,
• wherein the molar ratio of the sedative drug to the first lipid and the second lipid is equal to or higher than about 0.19 and wherein the sedative drug is encapsulated in the first liposome.