Cure in sight for HIV infection

Scientists have found a way of eradicating HIV infection from the human body by “smoking” out the virus from its hideout cells. The new approach is to kill the hideout cells plus the virus.

The current anti-Aids drugs only destroy viruses circulating in the body but some manage to hide in particular immune system cells and continue replicating, hence the patient has to remain on medication throughout.

The new development by a team of American and Canadian researchers is the second indication that a cure for the disease that continues to afflict more than 1.3 million Kenyans and many more globally may finally be within reach.

In February, researchers in California developed a gene therapy with the capacity of eradicate HIV from the body and have since put 12 people on clinical trials. The study is still ongoing though it is said to involve a complex process that could make it very expensive.

Radical new therapy

Published on Sunday in the Nature Medicine journal, the new study says HIV and Aids can be treated through a combination of targeted drugs together with current anti-retrovirals.

“This radical new therapy would make it possible to destroy both the viruses circulating in the body as well as those playing hide-and-seek in immune system cells,” says Dr Rafick-Pierre Sékaly, of the University of Montreal, Canada.

Other participating groups included the universities of McGill and Minnesota and the National Institutes of Health, the latter is the US federal agency responsible for overseeing government-sponsored biomedical research.

Current anti-retroviral treatments are not able to eradicate the virus from the body because some disease agents hide in particular cells where the existing treatments cannot reach. These researchers have now identified these cells and found a way of reaching them.

The new approach, says the team, is to use drugs to kill the cell containing the virus while giving the immune system time to regenerate with new cells. This could much cheaper that the gene-therapy technology.

“Once the virus is hidden in these reservoir cells, it becomes dependent on them: if the cell lives, the virus lives, but if the cell dies, so does the virus. As such, destroying these immune cells will allow for the elimination of the resilient or hidden parts of the virus,” says Dr Sekaly.

While the team acknowledges that a product is still several years away before becoming a reality for patients, they are excited of the breakthrough which they say opens the way for therapies that are completely different from current ones.

“We now have brand new options to fight HIV,” concludes Nicolas Chomont, of Montreal University and a co-author of the study.

The next step for researchers is to begin testing their proposed treatment method using animal models and newly developed therapies. The same approach is used in the treatment of leukaemia – cancer of blood or bone marrow.

The development comes at a time when local researchers at the University of Nairobi, collaborating with those from Manitoba University of Canada, have intensified efforts to find the gene that protects some Kenyan prostitutes from HIV infections despite repeated exposure to the virus.

The study conducted at Kenyatta National Hospital’s School of Medicine hopes to come up with a new way of designing a vaccine candidate.

Since last year the researchers have opened up new centres in Korogocho and Kangemi to study more prostitutes. The research will go on until 2010 and is expected to shed more light on why they are resistant to HIV infection.

But it is the new US-Canada study that offers more and possibly closer hope for over 260,000 Kenyans living on anti-retrovirals. Some of the drugs in use in Kenya present patients with serious side effects.

The government has been considering withdrawing several brands of anti-retroviral medicine that have been found to have severe side-effects, especially on women, according to the director of the National Aids/STDs Control Programme, Dr Nicholas Muraguri.

Although the incidence of HIV in Kenya is said to have stabilised in the last few years, there are still concerns over specific groups which include couples and steady partners, male prostitutes and surprisingly enough among medical personnel.

According to a World Health Organisation sponsored study and published on The Lancet on Saturday, the incidence of HIV and Aids in the health work force in Kenya is twice the national average, and death is the main cause of attrition.

The Africa-wide study, says 43 per cent of deaths or medical retirement of health workers were known or suspected to be caused by HIV and Aids, and 37 per cent were known or suspected to be due to TB. The study does not explain this trend.