In a recent study, a new HIV-1 vaccine regimen protected vaccinated monkeys against the primate version of the AIDS virus.

A recently completed study has bolstered hopes that a vaccine might soon be available for people infected with HIV.

A protein-boosted HIV-1 vaccine regimen provided complete protection in half of vaccinated monkeys, according to researchers who oversaw the study.

The experimental vaccine protected the monkeys against a series of episodes of simian immunodeficiency virus (SIV), the primate version of HIV.

The research was led by scientists at Beth Israel Deaconess Medical Center (BIDMC) and published today in the journal Science.

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The data from the study shows that adding a protein boost improved protection by increasing the magnitude of antibody responses, said Dr. Dan Barouch, lead author of the study and director of the Center for Virology and Vaccine Research at BIDMC as well as a professor of medicine at Harvard Medical School.

Barouch said he and his colleagues were encouraged by the results of the preclinical study, labeling them as “substantially better” than prior vaccines tested in this model.

The antibody responses “paves a path forward for future HIV-1 vaccine strategies for humans,” he added.

The HIV-1 version of this vaccine regimen is now being evaluated in an ongoing international clinical study sponsored by Crucell Holland B.V., one of the Janssen Pharmaceutical companies of Johnson & Johnson.

“It’s an exciting finding,” said Dr. Mary Marovich, director of the Vaccine Research Program at the National Institute of Allergy and Infectious Diseases. “Although this was an animal study — and more research must be done before we will know if this can work in humans — the researchers used a rigorous approach to testing the vaccine regimen.”

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