From the BBC: New antibody attacks 99% of HIV strains

"Scientists have engineered an antibody that attacks 99% of HIV strains and can prevent infection in primates.

It is built to attack three critical parts of the virus - making it harder for HIV to resist its effects.
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The study, published in the journal Science, combines three such antibodies into an even more powerful "tri-specific antibody".

Dr Gary Nabel, the chief scientific officer at Sanofi and one of the report authors, told the BBC News website: "They are more potent and have greater breadth than any single naturally occurring antibody that's been discovered."

The best naturally occurring antibodies will target 90% of HIV strains.

"We're getting 99% coverage, and getting coverage at very low concentrations of the antibody," said Dr Nabel.

Experiments on 24 monkeys showed none of those given the tri-specific antibody developed an infection when they were later injected with the virus."