Potent activity of 2'-beta-fluoro-2',3'-dideoxyadenosine against human immunodeficiency virus type 1 infection in hu-PBL-SCID mice.
A new antiretroviral agent, 2'-beta-fluoro-2',3'-dideoxyadenosine (FddA), is an acid-stable compound whose triphosphate form is a potent reverse transcriptase inhibitor with in vitro anti-human immunodeficiency virus (HIV) activity and a favorable pharmacokinetic profile. Severe combined immunodeficiency (SCID) mice reconstituted with human peripheral blood leukocytes (hu-PBL-SCID mice) provide a useful small-animal model for HIV research. In the present study we utilized this experimental system for the in vivo evaluation of the anti-HIV activity of this new compound when administered prior to infection. Initial studies revealed that, following a challenge with 50 100% tissue culture infective doses of HIV type 1 lymphadenopathy-associated virus, 39 of 42 (93%) control mice developed HIV infection, as evidenced by positive coculture or positive PCR. Administration of zidovudine decreased the infection rate to 5 of 16 (31%), while administration of FddA decreased the infection rate to 0 of 44 (0%). In follow-up controlled studies, the anti-HIV activity of FddA was confirmed, with 18 of 20 control mice showing evidence of HIV infection, compared with 4 of 20 FddA-treated mice. In addition to having direct anti-HIV effects, FddA was found to have a protective effect on human CD4+ T cells in the face of HIV infection. Mice treated with FddA were found to have a significantly higher percentage of CD4+ T cells than controls (10.3% +/- 3.4% versus 0.27% +/- 0.21%; P = 0.01). Thus, FddA, with its potent anti-HIV activity in vivo, high oral bioavailability, long intracellular half-life, and ability to preserve CD4+ cells in the presence of HIV, appears to be a promising agent for clinical investigation.
Ruxrungtham
K
K
Laboratory of Immunoregulation, National Institute of Allergy and Infectious Diseases, Bethesda, Maryland 20892, USA.
Boone
E
E
Ford
H
H
Driscoll
J S
JS
Davey
R T
RT
Lane
H C
HC
D000818:Animals; D019380:Anti-HIV Agents / Q000493:pharmacokinetics / Q000494:pharmacology*; D018791:CD4 Lymphocyte Count; D004279:DNA, Viral / Q000096:biosynthesis / Q000302:isolation & purification; D016048:Dideoxyadenosine / Q000031:analogs & derivatives* / Q000493:pharmacokinetics / Q000494:pharmacology; D005260:Female; D005434:Flow Cytometry; D015658:HIV Infections / Q000188:drug therapy* / Q000821:virology; D015497:HIV-1; D006207:Half-Life; D006801:Humans; D007120:Immunochemistry; D007074:Immunoglobulin G / Q000032:analysis; D051379:Mice; D016513:Mice, SCID; D016133:Polymerase Chain Reaction
D019380:Anti-HIV Agents; D004279:DNA, Viral; D007074:Immunoglobulin G; C055502:2-fluoro-2',3'-dideoxyadenosine; D016048:Dideoxyadenosine