Combo HIV Drug Therapy May Restore Healthy Immune System
THURSDAY July 19, 2007 -- People with HIV may be able to achieve normal CD4 counts -- a marker of immune system strength -- by taking combination antiretroviral drug therapy, says a new study.
In a study published early online July 19 and in an upcoming edition of The Lancet, researchers found that people with HIV who remain on combination drug treatment for long enough and have their HIV viral load suppressed to below 50 copies per milliliter could see their CD4 count rise to concentrations equal to those of people uninfected by HIV.
In the study, a British team at the Royal Free and University College London Medical Schools, studied 1,835 people with HIV who had not previously taken antiretroviral therapy. The participants had a mean CD4 count of 200 cells per microliter of blood and then started combination antiretroviral therapy. They were selected to participate in the study because they responded well to this treatment, and their HIV viral loads were suppressed to below 50 copies per milliliter for extended periods of time.
The greatest average yearly increase in CD4 count -- 100 cells per microliter -- was seen in the first year after starting combination drug therapy. In the years following, significant, but lower (50 cells per microliter), increases were seen.
The participants who started combo therapy with low CD4 cell counts (of less than 200 cells per microliter) had substantial rises in CD4 counts even after five years. The only groups without substantial increases in CD4 counts were those who had taken the therapy for more than five years with high current CD4 counts (more than 500 cells per microliter).
The authors concluded that people with HIV can normalize their CD4 counts with combinations of antiretroviral drugs if they can maintain their viral load at less than 50 copies per milliliter.
But, in an accompanying comment, Gary Maartens and Andrew Boulle from the University of Cape Town, South Africa, cautioned that the findings are only applicable to patients with ideal responses to combination antiretroviral drug therapy, possibly limiting their application in patients in poorer countries.
The World Health Organization has more about antiretroviral therapy.
Posted: July 2007