ROCKVILLE -- A new federal study has raised troubling questions about who will be helped by the AIDS drug AZT and how much.
The study, which was conducted by the Department of Veterans Affairs, found that AZT, or azidothymidine, slowed the development of symptoms in some people infected with the AIDS virus, yet people who took the drug before they had developed symptoms lived no longer than those who took it after they showed symptoms.
In addition, the researchers found that black and Hispanic patients showed little slowing in the development of symptoms.
They also fared no better when they took AZT before they developed symptoms than when they waited until they were ill.
The new study did not question the usefulness of the drug in treating acquired immune deficiency syndrome after the disease has developed.
The data were reviewed yesterday by a Food and Drug Administration committee charged with advising the agency on such matters as changing the way the drug is labeled for recommended uses.
The committee said it would be premature to change the label on AZT, which recommends its use in preventing the onset of AIDS. But it added that the data were disquieting, showed the need for further study and could not be ignored.
Several committee members said they would change the way they counseled patients in light of the new findings.
The recommendation to use AZT to prevent AIDS was first made by the Food and Drug Administration in 1989 after studies that showed the drug successfully postponed the onset of symptoms. But the studies were halted at that point, and the patients' overall survival rate was not measured.
The committee of the FDA urged extreme caution in interpreting the data from the new study relating to black and Hispanic patients, emphasizing that they could result from factors such as poverty and poor health care that could make members of minorities more sick to begin with.