Patent ID: 11918565
Assignee: PACIRA PHARMACEUTICALS, INC.
Field: Pharmaceuticals (Chemistry)
Classification: CPC A | IPC A

Claim 7:
8. The method of claim 1, wherein the multivesicular liposomes comprise:
bupivacaine or a salt thereof;
phosphoric acid;
a lipid component comprising at least one amphipathic lipid and at least one neutral lipid lacking a hydrophilic head group; and,
optionally, a cholesterol and/or a plant sterol,
wherein said multivesicular liposomes are made by a process comprising:
a) preparing a first aqueous component comprising phosphoric acid;
b) preparing a lipid component comprising at least one organic solvent, at least one amphipathic lipid, and at least one neutral lipid lacking a hydrophilic head group;
c) mixing said first aqueous component and said lipid component to form a water-in-oil emulsion, wherein at least one component comprises bupivacaine or a salt thereof;
d) mixing said water-in-oil emulsion with a second aqueous component to form solvent spherules; and
e) removing the organic solvent from the solvent spherules to form multivesicular liposomes encapsulating bupivacaine phosphate.