(This document has been abbreviated unchanged from the original document except for the bold emphasis editing by Stuart Thomson, Director, the Gaia Research Institute. S.T.) (We are keen to determine whether this research has been taken into consideration by the Medicines Control Council in its recent re-endorsement of this deadly toxic agent. S.T.)

TR-469
Toxicology and Carcinogenesis Studies of AZT (CAS No. 30516-87-1) and AZT/a-Interferon A/D B6C3F1 Mice (Gavage Studies)

3'-Azido-3'-deoxythymidine (AZT) is the most widely used and evaluated chemotherapeutic agent for the treatment of persons with acquired immune deficiency syndrome (AIDS) and persons seropositive for human immunodeficiency virus (HIV). The National Cancer Institute nominated AZT for toxicity and carcinogenicity studies because of the impending large-scale use of AZT in the treatment of adult patients with AIDS or AIDS-related complex.

Exposure to AZT was toxic to the bone marrow, resulting in significant changes in the peripheral blood (decreased hematocrit values, erythrocyte counts, and hemoglobin concentrations, and increased mean cell volume and mean cell hemoglobin) and bone marrow (erythroid hypoplasia) characteristic of a dose- and time-dependent, minimal to moderate, poorly regenerative macrocytic anemia.

Hematology and Bone Marrow Analyses

All groups of male and female mice receiving AZT exhibited changes in peripheral blood and bone marrow characteristic of a dose- and time-dependent, minimal to mild, macrocytic, nonresponsive anemia. In females, these changes were evident throughout the study. In males, the macrocytic anemia had resolved by week 80 in the 30 mg/kg group; at study termination erythrocyte macrocytosis was present only in males receiving 60 or 120 mg/kg AZT.

Pathology Findings

Incidences of squamous cell carcinoma and squamous cell papilloma or carcinoma (combined) of the vagina occurred with a positive trend and were significantly increased in groups of female mice receiving 60 or 120 mg/kg AZT. Epithelial hyperplasia was observed in all dosed groups of females, and the incidence was significantly increased in the 120 mg/kg AZT group.

Three renal tubule adenomas and one renal tubule carcinoma were observed in male mice receiving 120 mg/kg AZT; the combined incidence in this group exceeded the range in historical controls. Evaluation of step sections revealed a few more renal tubule hyperplasias.

The incidence of harderian gland adenoma was increased in male mice receiving 120 mg/kg AZT and exceeded the range in historical controls.

AZT is mutagenic in vitro and in vivo. It induced gene mutations in Salmonella typhimurium strain TA102. AZT induced sister chromatid exchanges in cultured Chinese hamster ovary cells. In vivo studies with male mice administered AZT by gavage showed highly significant increases in micronucleated erythrocytes in bone marrow and peripheral blood after exposure periods that ranged from 72 hours to 14 weeks.

Under the conditions of these 2-year gavage studies there was equivocal evidence of carcinogenic activity of AZT in male mice based on increased incidences of renal tubule and harderian gland neoplasms in groups receiving AZT alone. There was clear evidence of carcinogenic activity of AZT in female mice based on increased incidences of squamous cell neoplasms of the vagina in groups that received AZT.

Hematotoxicity occurred in all groups that received AZT.

Treatment with AZT resulted in increased incidences of epithelial hyperplasia of the vagina in all dosed groups of females.

Synonyms: AZT; 3'-azido-2',3'-dideoxythymidine; azidodeoxythymidine; azidothymidine; 3'-azidothymidine; 3'-deoxy-3'-azidothymidine; 3'-deoxy-(8CI) (9CI); BW A509U; Compound S; ZDV; zidovudine
Trade name: Retrovir®

Report Date: February 1999

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(Editor’s Comment: Preliminary data has for several years indicated that AZT represented unacceptable risks. Responsible scientists accordingly called for comprehensive testing such as that reported above, which is always mandatory prior to the approval of all other drugs before licensing. AZT (as is Fluoride) is unique in that it alone was approved for “human experimentation” prior to such animal studies having been conducted, and this for the treatment of a disease of widely scientifically disputed etiology. Existing pro-AZT studies are fraudulent in that they have been subject to serious methodological flaws and or were strategically terminated prematurely, prior to the drug revealing it’s true unacceptable risk / benefit profile and the paradoxical inevitable suppression of immunity, not similarly prevented by experimental termination in real-life applications of this drug. For insight into the fraudulent trials see: http://www.virusmyth.net/aids/data/jlfraud.htm S.T.)