Breakthrough as New Vaccine Clears HIV Virus in Monkeys

Global science has finally confirmed cure for Human Immune Virus (HIV), one of the world killer diseases as new studies have proved a vaccine for the monkey equivalent of HIV can eradicate the virus.

The latest report further explained that the new vaccine which cures simian immunodeficiency virus (SIV), an infection found in monkeys similar to HIV, would ultimately help scientists create a human version for HIV.

 In recent years, spates of findings have shown that HIV can essentially be eradicated in some patients.

Since then, scientists have been scrambling to ultimately find a cure that could drastically change the lives of millions of people worldwide.

Since the beginning of the epidemic, almost 70 million people have been infected with the HIV virus and about 35 million people have died of AIDS.

Globally, 34.0 million people were living with HIV at the end of 2011. Sub-Saharan Africa remains most severely affected, with nearly one in every 20 adults (4.9 per cent) living with HIV and accounting for 69 per cent of the people living with HIV worldwide.

In Nigeria, it is estimated that 3.4 million persons live with the virus.

According to the study from the Vaccine and Gene Therapy Institute at Oregon Health and Science University, published in the journal Nature, researchers tested the vaccine on 16 monkeys infected with an aggressive form of SIV called SIVmac239.

Nine of the 16 monkeys had the infection completely eliminated from their bodies.

These monkeys were still infection-free between one-and-a-half to three years later. Further research is needed to determine why the vaccine only worked on some monkeys. Researchers also hope to test how the vaccine affects monkeys already infected with SIV, and eventually, if the vaccine could work in humans.

A potential HIV vaccine is still years away. But recent research has developed two vaccines for other infectious diseases that could be available sooner.

Acquired Immune Deficiency Syndrome (AIDS) was first recognized as a new disease in 1981 when increasing numbers of young homosexual men succumbed to unusual opportunistic infections and rare malignancies.

A retrovirus, now termed human immunodeficiency virus type 1 (HIV-1), was subsequently identified as the causative agent of what has since become one of the most devastating infectious diseases to have emerged in recent history.

HIV-1 spreads by sexual, percutaneous, and perinatal routes, however, 80 per cent of adults acquire HIV-1 following exposure at mucosal surfaces, and AIDS is thus primarily a sexually transmitted disease.

But based on the latest discovery, the authors said that they will adopt similar approach adopted for the monkeys to test a vaccine for HIV in humans. Commenting, Prof Louis Picker, from the Vaccine and Gene Therapy Institute at Oregon Health and Science University, said: “It is 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 research team 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 vaccine is based on another virus called cytomegalovirus (CMV), which belongs to the herpes family.

It used the infectious power of CMV to sweep throughout the body. But instead of causing disease, it has been modified to spur the immune system into action to fight off the SIV molecules.

“It maintains an armed force, that patrols all the tissues of the body, all the time, indefinitely,” explained Prof Picker. The researchers gave rhesus macaque monkeys the vaccine, and then exposed them to SIV.

They found that at first, the infection began to establish and spread. But then the monkeys’ bodies started to respond, searching out and destroying all signs of the virus.

Of the monkeys that successfully responded to the vaccine, they were still clear of infection between one-and-a-half and three years later.

Prof Picker said his team was still trying to work out why the vaccination worked in only about half of the monkeys. “It could be the fact that SIV is so pathogenic that this is the best you are ever going to get.

There is a battle going on, and half the time the vaccine wins and half the time it does not,” he said. The researchers are now testing the vaccine to see if it can be used after SIV exposure to treat and potentially cure infected monkeys. They also want to see if the technique could work in humans.

Prof Picker said: “In order to make a human version, we have to make sure it is absolutely safe. We have now engineered a CMV virus which generates the same immune response, but has been attenuated (modified to lose its virulence) to the point where we think it is unequivocally safe.”

 This would first have to pass through the regulatory authorities, but if it does, he said he hoped to start the first clinical trials in humans in the next two years.

Commenting on the research, Dr Andrew Freedman, from Cardiff University School of Medicine, said: “This suggests that prophylactic vaccines – vaccines designed to prevent infection – using CMV vectors may be a promising approach for HIV. While they may not prevent the initial infection, they might lead to subsequent clearance, rather than the establishment of chronic infection.”