AIDS Drug Approved for Testing in Federal Program After Delays

A promising experimental AIDS drug that has been cited as a victim of delays in the federal AIDS drug-testing program is to be tested in a federally sponsored trial that received approval this week, federal officials said Friday.

U.S. Food and Drug Administration officials confirmed that on Thursday the FDA approved a six-month trial of oral dextran sulfate, a drug that in laboratory tests has been found to prevent the AIDS virus from infecting and killing immune-system cells.

The trial, to involve 60 patients, is to begin later this month at medical centers in San Francisco and Boston, officials said. It is intended to determine the dose ranges within which to test the drug in subsequent, expanded trials of its effectiveness.

Dextran sulfate, which is available without prescription in Japan as an anti-coagulant to treat blood clots, has attracted great interest among people with AIDS in the United States, largely because studies in test tubes have found it effective against the virus.

Activists in the AIDS treatment community say many hundreds of Americans are already taking the drug without proof that it is safe or that it works. In recent months, some have said it has become increasingly difficult to buy it in Japan.

The National Institute of Allergy and Infectious Diseases had also placed the drug last November on its list of priority drugs for testing against AIDS. But institute officials have said shortages of federal manpower have delayed testing of promising drugs.

Purchasing Difficulties

Dr. Anthony S. Fauci, director of the institute, testified at a congressional hearing in Washington in April that trials of dextran sulfate were among those that had been delayed. Among the reasons he cited were difficulties purchasing and studying the drug.

Dextran sulfate will now become one of more than a dozen AIDS drugs being tested in the institute’s clinical trials program. Half of all AIDS drug testing in the United States is being done through that federal program; the other half is being done by drug manufacturers.

In late April, researchers at the National Cancer Institute reported that laboratory tests with dextran sulfate had found that it prevented the AIDS virus from infecting and killing the body’s T-cells, the main target of the deadly virus.

Researchers’ Warning

But the researchers warned it remained to be seen whether the drug would work in humans.

Last month, at the international AIDS conference in Stockholm, Dr. Donald Abrams of San Francisco General Hospital reported that dextran sulfate was “well tolerated” by patients in a preliminary, so-called phase one study sponsored by the drug’s manufacturer.

The new trial will build upon the findings made by Abrams, who will also be involved in the federal study, Brad Stone, a spokesman for the FDA, said Friday. The drug will be provided by the manufacturer, Ueno Fine Chemicals Ltd. of Osaka, Japan, which holds a patent for its use against AIDS.

To be admitted to the trial, patients will have to have evidence of AIDS virus proteins in their blood.