Results of drug trial cut short Thai AIDS experiment Short course of AZT halves transmission of virus from mother to baby

A headline in yesterday's editions incorrectly characterized the results of an AIDS drug trial in Thailand. The trial was completed, not cut short.

The Sun regrets the error.


The U.S. Centers for Disease Control and Prevention announced yesterday that a short course of the drug AZT sharply reduced transmission of the AIDS virus from mothers to babies in a Thailand experiment -- offering hope to impoverished countries that cannot offer expensive therapies.

The finding could end months of rancorous debate over the ethics of medical trials in the Third World, in which U.S. researchers provide the anti-AIDS drug to some women and placebos to others.


Critics have charged that the dummy pills needlessly deny a proven AIDS treatment to women and endanger the lives of their infants.

Citing the new findings, the CDC said yesterday that it would suspend the use of placebos in a continuing trial in the Ivory Coast and administer AZT to all participants.

Meanwhile, the Johns Hopkins School of Public Health announced it would similarly alter plans for AIDS-prevention trials in Ethiopia and Uganda.

"In light of these results, our investigators will have to take a long and hard look at the design of our studies," said the dean, Dr. Alfred Sommer.

An international meeting will soon be held to discuss the policy implications of the findings, according to a joint statement by the National Institutes of Health, the United Nations AIDS program and the French National Agency for AIDS Research.

There, officials are expected to recommend that placebos not be used in any of the trials involving mothers and infants.

Controversy over a series of U.S.-sponsored experiments erupted last April, when the watchdog organization, Public Citizen Health Research Group, said placebos would never be tolerated in the United States because AZT has already been shown to reduce mother-to-infant transmission.

Scientists, meanwhile, maintained that the placebos were the only way they could assess the drugs' effectiveness in societies where sick patients commonly receive little or no health care.


The studies -- some in progress and others in the planning stages -- aim to find cheap and effective alternatives to a $1,000 regimen that cuts transmission by two-thirds in the United States and other industrialized nations.

Women are given AZT orally during pregnancy and intravenously during delivery, and their babies receive it during the first few weeks of life.

Yesterday, the CDC announced that interim evidence from its Thailand study showed "conclusively" that a shortened course of AZT -- given orally to the mother in the late stages of pregnancy -- cut transmission in half.

About 19 percent of the babies got the AIDS virus from their mothers when no drug was given, compared with 9.2 percent when AZT was used.

The simplified regimen costs about one-tenth as much as the therapy being used in Western nations.

It also does not involve intravenous equipment, which requires medical facilities that many countries cannot afford and spreads disease when sanitation is poor.


"Now, we're a step closer to seeing the kind of progress that we've made at home extended to the developing world," said Health and Human Services Secretary Donna E. Shalala.

Dr. Peter Lurie, a researcher with Public Citizen, said the new data merely confirm what he and other critics of the experiments have said all along.

"I think it certainly settles the debate in that there should be no more trials in which people are denied access to AZT," he said.

"The broader question is whether people have learned that trials for HIV or any other disease need to adhere to the very same ethical principles they would if conducted in an industrialized country."

Sommer said researchers remained in a difficult position because they cannot -- on the basis of one study -- conclude that the shortened treatment will be equally effective everywhere.

"We'll have to look for ingenious ways not to use placebos but still come up with confirming data," Sommer said.


To do this, scientists might compare the short courses with longer courses -- or, perhaps, with even more simplified regimens.

Pub Date: 2/19/98

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