Research carried out by the European- Australian Collaborative Group found the treatment appeared to cut in half the chances that patients' conditions would get worse over the next two years.
The investigations contradict the European-based Concord study of patients carrying the HIV virus but showing no Aids symptoms, which found no significant benefit from early therapy. That study was based on a different definition of worsening disease than the latest research.
Doctors agree that AZT eventually loses its power against the virus. But the authors of the latest study said the evidence suggests that when given early, the medicine is beneficial for two to three years.
Scientists working on the latest study, conducted on 993 HIV-infected volunteers in 11 countries, found after two years of treatment there was a 19 per cent chance the disease would get worse among AZT recipients.
However, the risk of disease progression was 34 per cent in those getting inactive placebos.
Another major study, begun in 1987 on 3,200 patients in the United States, found that early treatment with AZT appeared to help.Reuse content