Biomaterial Database

AZT toxicity and AIDS prophylaxis: is AZT beneficial for HIV+ asymptomatic persons with 500 or more T4 cells per cubic millimeter? 1995

M D Zaretsky

Department of Molecular and Cell Biology, University of California, Berkeley 94720, USA.

Analyses of the effects of prophylactic use of zidovudine (AZT) on progression to acquired immune deficiency syndrome (AIDS) in human immunodeficiency virus seropositive (HIV+) asymptomatic persons with T4 lymphocyte (CD4+) cell counts > or = 500/mm3 is reported for data obtained from two studies, the Australian European Group Collaborative Study, a multi-centered double-blind placebo-controlled clinical trial of the effects of AZT on progression to AIDS and other clinical endpoints, and the San Francisco Men's Health Study, an observational cohort. The analyses of the data of both studies demonstrate no benefit from AZT treatment in terms of progression to AIDS for those who are asymptomatic with CD4+ cell counts > or = 500/mm3. The analysis of the San Francisco study, performed with Kaplan-Meier survivorship estimates, indicates a heterogeneity in the efficacy of AZT between baseline CD4+ cell count strata, 200-499/mm3 and 500-800/mm3. Within the 200-499 stratum, 47% of those receiving AZT therapy and 62% of those not receiving AZT therapy progressed to AIDS during the study period. By contrast, within the 500-800 stratum 41% of those receiving AZT therapy and 27% of those not receiving AZT therapy progressed to AIDS during the same period. Application of the Cox proportional hazards survivorship regression model for the relative risk of progression to AIDS to these same data accounts for this heterogeneity. The model includes an interaction between AZT treatment and baseline CD4+ cell counts. The hematological toxicity of AZT, demonstrated in clinical studies and laboratory investigations, indicates a biological correlate for this interaction: the toxic effects of AZT on the more intact immune system of those with CD4+ cell counts in the 500-800/mm3 range [corrected].

UI	MeSH Term	Description	Entries
D007107	Immune System	The body's defense mechanism against foreign organisms or substances and deviant native cells. It includes the humoral immune response and the cell-mediated response and consists of a complex of interrelated cellular, molecular, and genetic components.	Immune Systems,System, Immune,Systems, Immune
D008297	Male		Males
D004311	Double-Blind Method	A method of studying a drug or procedure in which both the subjects and investigators are kept unaware of who is actually getting which specific treatment.	Double-Masked Study,Double-Blind Study,Double-Masked Method,Double Blind Method,Double Blind Study,Double Masked Method,Double Masked Study,Double-Blind Methods,Double-Blind Studies,Double-Masked Methods,Double-Masked Studies,Method, Double-Blind,Method, Double-Masked,Methods, Double-Blind,Methods, Double-Masked,Studies, Double-Blind,Studies, Double-Masked,Study, Double-Blind,Study, Double-Masked
D005260	Female		Females
D006679	HIV Seropositivity	Development of neutralizing antibodies in individuals who have been exposed to the human immunodeficiency virus (HIV/HTLV-III/LAV).	AIDS Seroconversion,AIDS Seropositivity,Anti-HIV Positivity,HIV Antibody Positivity,HIV Seroconversion,HTLV-III Seroconversion,HTLV-III Seropositivity,AIDS Seroconversions,AIDS Seropositivities,Anti HIV Positivity,Anti-HIV Positivities,Antibody Positivities, HIV,Antibody Positivity, HIV,HIV Antibody Positivities,HIV Seroconversions,HIV Seropositivities,HTLV III Seroconversion,HTLV III Seropositivity,HTLV-III Seroconversions,HTLV-III Seropositivities,Positivities, Anti-HIV,Positivities, HIV Antibody,Positivity, Anti-HIV,Positivity, HIV Antibody,Seroconversion, AIDS,Seroconversion, HIV,Seroconversion, HTLV-III,Seroconversions, AIDS,Seroconversions, HIV,Seroconversions, HTLV-III,Seropositivities, AIDS,Seropositivities, HIV,Seropositivities, HTLV-III,Seropositivity, AIDS,Seropositivity, HIV,Seropositivity, HTLV-III
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000163	Acquired Immunodeficiency Syndrome	An acquired defect of cellular immunity associated with infection by the human immunodeficiency virus (HIV), a CD4-positive T-lymphocyte count under 200 cells/microliter or less than 14% of total lymphocytes, and increased susceptibility to opportunistic infections and malignant neoplasms. Clinical manifestations also include emaciation (wasting) and dementia. These elements reflect criteria for AIDS as defined by the CDC in 1993.	AIDS,Immunodeficiency Syndrome, Acquired,Immunologic Deficiency Syndrome, Acquired,Acquired Immune Deficiency Syndrome,Acquired Immuno-Deficiency Syndrome,Acquired Immuno Deficiency Syndrome,Acquired Immuno-Deficiency Syndromes,Acquired Immunodeficiency Syndromes,Immuno-Deficiency Syndrome, Acquired,Immuno-Deficiency Syndromes, Acquired,Immunodeficiency Syndromes, Acquired,Syndrome, Acquired Immuno-Deficiency,Syndrome, Acquired Immunodeficiency,Syndromes, Acquired Immuno-Deficiency,Syndromes, Acquired Immunodeficiency
D015215	Zidovudine	A dideoxynucleoside compound in which the 3'-hydroxy group on the sugar moiety has been replaced by an azido group. This modification prevents the formation of phosphodiester linkages which are needed for the completion of nucleic acid chains. The compound is a potent inhibitor of HIV replication, acting as a chain-terminator of viral DNA during reverse transcription. It improves immunologic function, partially reverses the HIV-induced neurological dysfunction, and improves certain other clinical abnormalities associated with AIDS. Its principal toxic effect is dose-dependent suppression of bone marrow, resulting in anemia and leukopenia.	AZT (Antiviral),Azidothymidine,3'-Azido-2',3'-Dideoxythymidine,3'-Azido-3'-deoxythymidine,AZT Antiviral,AZT, Antiviral,BW A509U,BWA-509U,Retrovir,3' Azido 2',3' Dideoxythymidine,3' Azido 3' deoxythymidine,Antiviral AZT,BWA 509U,BWA509U
D015331	Cohort Studies	Studies in which subsets of a defined population are identified. These groups may or may not be exposed to factors hypothesized to influence the probability of the occurrence of a particular disease or other outcome. Cohorts are defined populations which, as a whole, are followed in an attempt to determine distinguishing subgroup characteristics.	Birth Cohort Studies,Birth Cohort Study,Closed Cohort Studies,Cohort Analysis,Concurrent Studies,Historical Cohort Studies,Incidence Studies,Analysis, Cohort,Cohort Studies, Closed,Cohort Studies, Historical,Studies, Closed Cohort,Studies, Concurrent,Studies, Historical Cohort,Analyses, Cohort,Closed Cohort Study,Cohort Analyses,Cohort Studies, Birth,Cohort Study,Cohort Study, Birth,Cohort Study, Closed,Cohort Study, Historical,Concurrent Study,Historical Cohort Study,Incidence Study,Studies, Birth Cohort,Studies, Cohort,Studies, Incidence,Study, Birth Cohort,Study, Closed Cohort,Study, Cohort,Study, Concurrent,Study, Historical Cohort,Study, Incidence
D015496	CD4-Positive T-Lymphocytes	A critical subpopulation of T-lymphocytes involved in the induction of most immunological functions. The HIV virus has selective tropism for the T4 cell which expresses the CD4 phenotypic marker, a receptor for HIV. In fact, the key element in the profound immunosuppression seen in HIV infection is the depletion of this subset of T-lymphocytes.	T4 Cells,T4 Lymphocytes,CD4-Positive Lymphocytes,CD4 Positive T Lymphocytes,CD4-Positive Lymphocyte,CD4-Positive T-Lymphocyte,Lymphocyte, CD4-Positive,Lymphocytes, CD4-Positive,T-Lymphocyte, CD4-Positive,T-Lymphocytes, CD4-Positive,T4 Cell,T4 Lymphocyte