Liposomes as carriers of the antiretroviral agent dideoxycytidine-5 '-triphosphate

The presence and replication of the human immunodeficiency virus (HIV) in c ells of the mononuclear phagocyte system (MPS) together with the preferenti al uptake of liposomes in macrophages suggest that liposomes can become a v aluable carrier of anti-HIV agents. Moreover, liposomes reduce toxicity of encapsulated drugs and protect encapsulated drugs against rapid degradation in the blood circulation. To overcome problems associated with the adminis tration of fret: nucleosides and to improve targeting to the MPS, dideoxycy tidine-5'-triphosphate (ddCTP) was encapsulated in liposomes. Liposomes wer e stable with regard to retention of the entrapped drug, particle size and chemical stability of ddCTP. Results obtained with liposome encapsulated dd CTP in the murine acquired immunodeficiency syndrome (MAIDS) model indicate that ddCTP encapsulated in liposomes can reduce proviral DNA in cells of t he mononuclear phagocyte system (MPS) in both spleen and bone marrow. (C) 1 999 Elsevier Science B.V. All rights reserved.