A vaccine designed to tackle SIV, the monkey equivalent of HIV, may have successfully cleared the virus from infected animals, paving the way for research into a HIV vaccine for humans.

A research team at the Vaccine and Gene Therapy Institute at Oregon Health and Science University looked at an aggressive form of virus called SIVmac239, which is up to 100 times more deadly than HIV.

Infected monkeys usually die within two years, but in some inoculated primates the virus did not take hold.

The study published in the science journal Nature showed that of 16 monkeys exposed to the virus who were injected with a vaccine, nine appeared to be able to clear their body of the disease.

Prof Louis Picker, from the Vaccine and Gene Therapy Institute at Oregon Health and Science University, said: “It’s always tough to claim eradication – there could always be a cell which we didn’t analyse that has the virus in it. But for the most part, with very stringent criteria… there was no virus left in the body of these monkeys.”

The team want to examine if the same technique could be developed and made safe enough to be successful in humans. Clinical human trials could start within two years if the vaccine is approved and the team receive permission from regulatory bodies.