Some early trial data on a candidate AIDS vaccine appear promising, although an effective AIDS vaccine remains an elusive goal, researchers reported Thursday.
Scientists at the Johns Hopkins School of Public Health, Baltimore, said in the journal The Lancet that an experimental vaccine produced antibodies against two strains of HIV in nine of 10 patients who were injected with it.The problem facing researchers is developing a vaccine that works against a variety of AIDS virus strains.
The results represent a "small but valuable incremental step forward," said Dr. David Schwartz, the report's lead author.
He said much work remains to be done to develop a vaccine that produces antibodies against multiple strains of HIV and to determine how to make any immunity last, he said, but researchers are making real progress.
"By the year 2000, I think it is realistic to think there will be a vaccine in trial for efficacy," Schwartz said.
The experimental vaccine Schwartz studied, developed by Genentech Inc., of South San Francisco, uses a different approach from some earlier trial vaccines. It uses only a "subunit" - a tiny, key element - of the human immunodeficiency virus' envelope protein.
If the vaccine works, it teaches the immune system how to recognize HIV and fight it. But because it only is a fragment of the vaccine, there is no risk of infection.