A potential HIV vaccine has been developed.

The new drug candidate was found to block every strain of HIV isolated from humans, including the variants of the virus hardest to stop.

The drug was found to protect against higher doses of the human immunodeficiency virus (HIV) than would happen in most human to human transmission and lasts up to eight months after injection, a study at the Scripps Research Institute claimed.

Data from the study showed the drug candidate bound to two sites on the surface of the virus, preventing entry of HIV into the host cell.

HIV is a virus that attacks the immune system, affecting an individual’s ability to fight infections and disease. Acquired immune deficiency syndrome (AIDS) is the final stage of HIV.

The virus is transmitted through unprotected sex with someone who is HIV-positive or by sharing infected needles.

“Our compound is the broadest and most potent entry inhibitor described so far,” said lead researcher, Michael Farzan.

“Unlike antibodies, which fail to neutralise a large fraction of HIV-1 strains, our protein has been effective against all strains tested, raising the possibility of an effective HIV vaccine alternative.”

Delivery vehicles - in the form of a non-infective virus - were designed to carry the drug into the body. It is claimed once injected into muscle tissue, the cells are turned into “factories” that could produce enough of the new protective protein to last for ßdecades, according to Farzan.