Ground-breaking research aimed at using short courses of anti-retroviral drugs to boost the long-term immunity of babies with HIV is due to begin within weeks at St Mary’s Hospital in Marianhill, outside Durban.  

If this world-first clinical trial works, it offers huge advantages for Africa as it will mean that the cost of anti-retroviral treatment to keep   HIV in check will be greatly reduced and there is less danger of drug toxicity.

Sixty babies will be given anti-retroviral drugs at set intervals — called structured treatment interruption — in the hope that this will permanently enhance their bodies’ ability to fight HIV.

The experiment is based on the idea that, in the early stages of HIV infection, the immune system can hold HIV in check if there is enough virus in the bloodstream (viral load) for the infection-fighting white cells (CD4 cells) to recognise and destroy it.

Later, however, the virus usually gains the upper hand by destroying these white blood cells. But in the St Mary’s experiment, the scientists aim to prevent the virus from reaching dangerous levels by re-introducing anti-retroviral drugs as soon as the babies’ viral loads rise above a certain level.

The trial is a collaboration between the Nelson R Mandela Medical School, represented by Professor Jerry Coovadia and Dr Photini Kiepiela, and Harvard Medical School, represented by Dr Bruce Walker and Dr Philip Goulder  

“Our research has shown that structured treatment interruption for adults newly infected with HIV can prevent the worst effects of the disease by boosting their immune responses so that they can live for long periods without the drugs,” said Dr Walker during a recent visit to South Africa.  

However, the results in adults are still inconclusive and there is a danger of drug resistance developing.  

“Structured treatment interruption only works if the HIV infection is caught early and hit hard,” says Professor Coovadia. “The beauty about working with babies is that their immune systems are still so pristine.”  

The trial will involve three sets of babies: those infected in the womb (HIV positive at birth), those infected during birth (HIV negative at birth but HIV positive at six weeks) and those infected by breastfeeding (HIV negative at birth and at six weeks, but HIV positive at 13 weeks).

The babies will be given a drug cocktail of AZT, 3TC, Nevirapine and Nelfinavir, all of which have been used on children (but not newborns) in the US “for a long time”, says Prof Coovadia.

Drug treatment will be interrupted once the scientists are satisfied that the babies’ viral load is undetectable (less than 400 copies of the virus per millilitre of blood) for at least two weeks before treatment is interrupted, says Dr Kiepiela.

“The babies will be monitored every fortnight and kept off the treatment until their viral loads increase to 5 000 copies whereupon treatment will be restarted,” she adds.

“The absolute cherry on the top would be for the drugs to knock out the virus altogether, but that is more a dream,” says Prof Coovadia.  

“The next best result would be that, for protracted periods after treatment, the babies are able to attain normal growth and development and are free from the usual illnesses that come with HIV infection.  

“The treatment would prolong the life span of HIV-infected children beyond the brief and troubled years that usually characterise such kids,” says Prof Coovadia. “Maybe things will change in their lifetime and we will get a vaccine or anti-retroviral drugs will become more affordable.”

Significantly, the scientists have also committed themselves to giving anti-retroviral treatment to the babies and those in their immediate families who need it for five years, even though results are expected within three years.

“The study is ethically faultless,” says Prof Coovadia. “We are not simply narrowly focusing on the glamorous scientific aspects. We are offering anti-retroviral treatment to the mothers, fathers and siblings if they need it.”

The Medicines Control Council and a Harvard ethics committee have both given the trial the go-ahead, and the scientists will begin setting up the clinic next week.

The US-based Doris Duke Charitable Foundation is contributing $2,5-million (about R27,5-million) to the study, while Bristol-Myers Squibb’s “Secure the Future” has given R7-million.

Doris Duke is also contributing $1,5-million (R16,5-million) to building a new centre at the Nelson R. Mandela Medical School to house the research, the first new building on the campus since 1950.

“Dr Walker is one of the most outstanding scientists in the US,” said Doris Duke’s Dr Elaine Gallin. “We met the group he was working with in South Africa and were very impressed, as they are doing first class HIV research. “We are thrilled to be contributing to the fight against HIV in South Africa.”

Dr Walker believes that the Harvard-Mandela collaboration “should help to reverse the brain drain” by ensuring that promising young South African   scientists have the opportunity to do “cutting edge research” in their own country.