The pharmacological efficacy of a rigid non-phospholipid liposome drug delivery system.

Hydration of an ethoxylate derivative of cholesterol, triethoxycholesterol, results in the formation of stable, rigid, bilayer-like structures capable of encapsulating polar compounds. Studies on the stability and tissue distribution of these liposomes in mice indicate that they are suitable as a drug delivery system. Intraperitoneal injection of triethoxycholesterol encapsulated methotrexate into mice bearing hepatoma ascites tumor results in a doubling of the survival time, relative to untreated mice and those receiving unencaptulated drug. These studies show that fluid, acyl chains are not required for the formation of pharmacologically useful vesicles and that such formulations need not be limited to phospholipid-containing systems.