Johannesburg - A fourth case that could potentially bring a breakthrough in research seeking an HIV cure has come to light.

After the case of a Mississippi baby in March last year, where a newborn was put on high doses of three antiretroviral drugs only 31 hours after birth, the same approach, which is believed to have cured the baby, has shown similar results on an adult this time.

During the International Congress on Infectious Diseases in Cape Town last week, Deborah Persaud, a virologist and pediatric HIV expert at Johns Hopkins University, said that last month Hiroyu Hatano’s team at the University of California San Francisco had conducted a pre-exposure prophylaxis trial on an adult, who after contracting HIV, was put on highly active antiretroviral therapy (Haart) and now scientists cannot find traces of the virus in her CD4 blood cells.

Persaud, who last month broke the news that a second baby born with HIV had also shown no HIV traces after the same intervention as with the Mississippi baby, said scientists saw a very promising path in very early therapy.

While presenting her topic about the pathways to cure HIV at the congress, Persaud said there were many approaches under consideration to cure HIV.

She said if they could identify and try this approach of enrolling more recently infected adults on pre-exposure prophylaxis trials, perhaps a few more individuals could have the same outcome.

“The data emerging on very early treatment – curing early infection – those are promising leads in terms of one approach that may get us to some finishing line faster than others.

“We are still in the infancy stage but it’s a step in the direction that we need to go in,” Persaud said

She said the Mississippi baby, who was now 41 months old, still had no traces of HIV even when tested with an ultrasensitive DNA test which had not been used before.

While it was not clear how cost effective some approaches would be, Persaud said it made more sense for researchers to further investigate the Haart approach at a very early stage of HIV contraction given the large numbers of people who were on antiretroviral treatment and the cost implications for those who developed inflammatory side effects.

Other approaches under investigation were hemotopoetic stem cell transplant and latency-reversing agents. Two clinical studies were under way to investigate whether small molecules of these reversing agents could kick HIV out of latency.

Latency is a stage after early infection where HIV develops in a person’s immune system without producing symptoms.

A clear trial on these agents was being done in Denmark and a second involving Vorinostat multidosing was under way in Melbourne, Australia.

On the stem-cell transplant research, only one case so far had shown desired results.

The case involving a Berlin leukaemia patient showed a complete clearance of HIV infected cells. And after almost five years without taking any antiretroviral treatment, Persaud said HIV was still not detectable in his system.

Like all cancer patients, he had been given drugs that completely cleared cancerous cells in his immune system. However, the cells donor in this case had CD4 cells with a special genetic mutation. The cells, which the HIV infects, were resistant to the virus.

The only other cases that came close to reflecting the same results with this method were two cancer patients in Boston. But on their cases, cell donors did not have these specialised cells and the patients did not achieve whole body cell eradication.

After stopping antiretroviral treatment for some time, the HIV rebounded.

“It’s not clear fully what led to curing the Berlin patient. He had intensive chemotherapy, whole body eradication, two transplants with specialised cells and what’s called graft versus host disease. So multiple factors may have contributed,” Persaud said.

She said research on this was also continuing. - Business Report