ATLANTA (AP) _ Cocaine speeded the growth of the AIDS virus in laboratory tests, prompting concern that it could increase infected people's chances of developing the deadly disease, researchers reported Monday.

Microbiologists at the University of Minnesota Medical School exposed cells that are the primary target for the AIDS virus to doses of cocaine. The virus, HIV, was found to grow as much as three times faster in the cocaine-laced tests than in control studies.

If what happened in the test tube happens in HIV-infected cocaine users, it could increase their risk of developing AIDS, said Dr. Ronald Schut, the lead researcher.

''In persons who are infected, if they continue to abuse this drug it may have a significant impact on the development of clinical AIDS,'' Schut said.

While about 150,000 AIDS cases have been reported in the United States, researchers say a million or more other Americans are infected and at risk of developing AIDS.

Test-tube tests, however, don't always mimic what happens in the human body. The question now for researchers is whether drug use somehow modifies the immune system to enhance HIV growth in humans.

''The initial in-vitro (test-tube) studies suggest that it's possible,'' Schut said.

Schut presented the findings at the Interscience Conference on Antimicrobial Agents and Chemotherapy, sponsored by the American Society for Microbiology.

Further studies are under way using immune cells from drug users in a methadone program, where cocaine use is high, ''to see if the virus grows easier,'' Schut said.

Dr. James Curran, director of the Division of HIV-AIDS at the U.S. Centers for Disease Control, said little if any solid information is available concerning the AIDS risk of cocaine users. He added that drug users are notoriously difficult to study and many cocaine users are involved in injectable drug abuse, which can spread HIV by dirty needles.

Nearly one-fourth of the AIDS cases reported in this country stem from intravenous drug use, according to the CDC.

Curran said that while the Minnesota test results may be correct, of greater concern is the practice of trading cocaine for sex, leading to the spread of the AIDS virus by sexual contact.

Still, as far as cocaine is concerned, Curran said, ''I think it's safe to recommend don't do it.''

Also at the microbiology conference Monday:

- Curran predicted that homosexual men will still make up ''a large proportion'' of AIDS cases five years from now, despite the increase in AIDS among intravenous drug users and their sex partners. Half of last year's AIDS cases in the United States involved gay men, he said.

- Dr. Douglas Richman, an AIDS specialist at the University of California, San Diego, predicted that even without an AIDS vaccine, combination drug treatments will enable infected people to live ''normal'' lives and approach normal lifespans.

''A patient with HIV will be treated similarly to a patient with diabetes or hypertension - prevent the progression of disease and maintain the quality of life,'' Richman said.

Complications from high blood pressure and diabetes can be controlled and reduced with drug treatment, and so will various complications of HIV infection, he said.

- Development of an AIDS vaccine is ''a concept that is achievable,'' said Dr. Lawrence Corey, an AIDS specialist at the University of Washington in Seattle. But ''cocktail'' vaccines, combating various HIV strains, aren't at the human trial stage yet, and the protection offered by some vaccines tested in animals has tended so far to be quite short in duration, he said.

Because of the risk involved in testing a whole-virus AIDS vaccine, it's more likely that researchers will aim for development of a ''sub-unit'' vaccine, utilizing only pieces of the AIDS virus, he said.