Research into combination antiretroviral therapy (cART) has shown that long-term treatment can re-establish the immune functions of HIV patients to a healthy level. Individuals infected with the HIV virus suffer from a serious decrease in CD4 lymphocytes, a type of white blood cell central to the body’s immune system. The study, carried out by the Royal Free Centre for HIV Medicine and the Royal Free and University College London Medical Schools, and funded by the European Commission, showed that cART can effectively increase the number of CD4 cells in HIV patients until levels resemble those of healthy individuals.

The study formed part of a larger EU funded research project, EuroSIDA, and involved 1,835 HIV positive participants who were selected on the basis of their having responded well to cART treatment. At the beginning of the study the average CD4 cell count was 204 cells per microlitre of blood (in a healthy individual the CD4 cell count is between 500 and 1500). The average increase in the first year of treatment was around 100 cells per microlitre. While cell numbers continued to increase as the treatment went on, the annual increase tended to be lower than that of the initial year. It  also appeared that the patients with the lowest CD4 cell counts (200 or less) gained the most from the treatment, many continuing to show substantial increases even after five years, whereas those who began with a cell count of more than 500 showed far less improvement.

The findings are encouraging but by no means provide an answer. Participants were chosen specifically because they responded well to the cART treatment. There are still many HIV positive patients who do not benefit from such therapy. Additionally, many cannot access such treatment. In African countries such as Zimbabwe which have the highest HIV prevalence figures in the world, prospects of treatment remain poor. It is currently estimated that 0.6 per cent of the world’s population is affected by the HIV virus, with AIDS claiming over 25 million lives since its discovery at the beginning of the 1980s.

Walueurope
20 July 2007

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