Vaccine cocktail will cure HIV, experts hope

A VACCINE that prevents HIV spreading could be on the horizon after scientists discovered a combination of injections that cuts the infection rate in monkeys by four-fifths.

Scientists said a combination of three vaccines protected monkeys which were repeatedly exposed to the SIV virus – the simian version of the human immunodeficiency virus.

A study published in the journal Nature found that a mixture of injections cut the chances of monkeys contracting SIV by more than 80 per cent.

And in animals that did end up infected, the combination of vaccines “substantially” reduced levels of SIV in the blood, minimising its impact on their health.

The study is the first to uncover a vaccine that actively stops the virus from being acquired.

Most drugs that have been developed so far have merely been able to control levels of the virus post-infection, with previous studies that claimed to prevent infections dismissed as inaccurate or too small-scale.

Researchers from Harvard University believe they have some insight into how the combination of chemicals worked.

They think special “Env” antibodies that work against the outer “envelope” of the virus are most likely to help prevent it from entering the body.

Other approaches aimed at T cells – white blood cells that help mediate infection – were found to help manage levels of the virus in the body, rather than prevent infection.

Results of the study offer a glimmer of hope to scientists who have been trying to find a cure since HIV was first identified 30 years ago.

While the virus can now be effectively managed using powerful drugs, scientists have so far been unable to come up with a cure or vaccine to prevent transmission in the first place.

Study author Dr Dan Barouch said: “This study allowed us to evaluate the protective efficacy of several ‘prime-boost’ vaccine combinations, and this data will help guide the advancement of the most promising candidates into clinical trials.

“We have clearly shown that including Env in the vaccine is beneficial. The findings also suggest that a substantial degree of protection can be achieved against stringent virus challenges.”

A spokesman for the Terrence Higgins Trust Scotland said any research that would help prevent HIV infection was to be welcomed, but warned it could be many years before a vaccine for humans was developed.

He said: “Terrence Higgins Trust welcomes this promising development in vaccine research to prevent HIV infection. This particular research is at an early stage of development and it will be some years off before the findings can be taken forward to trials on human subjects.

“But it is encouraging that there have been a number of recent developments in HIV vaccine research after decades of disappointment on this front.

“Canadian researchers have recently been given the go-ahead by regulators to start human trials on an HIV vaccine there, so there is significant progress in this field and hope for a vaccine that works effectively in humans in the not-too-distant future.”