Cellular proviral HIV-DNA decline and viral isolation in naive subjects with < 5000 copies/ml of HIV-RNA and > 500 x 10(6)/I CD4 cells treated with highly active antiretroviral therapy

Objective: To evaluate the decay rate of cellular proviral HIV-DNA and vira l replication in patients receiving highly active antiretroviral therapy (H AART) in the very early phase of infection. Methods: Thirty-four patients treated with HAART and retrospectively select ed for progressive decline of plasma viraemia up to undetectable levels (< 20 copies/ml), were stratified according to CD4+ cell count and plasma vira emia at base line: > 500 x 10(6) cells/l with < 5000 copies/ml (group 1) or with > 5000 copies/ml (group 2), > 5000 copies/ml with 300-500 X 10(6) cel ls/l (group 3) or with < 300 X 10(6) cells/ I (group 4). Plasma HIV-RNA and proviral HIV-DNA were analysed at baseline and after 1,2, 3, 6, 9 and 12 m onths of treatment. Results: After 1 year of treatment, a significant decrease of proviral DNA titre was observed in all patients and a decrease > 1 log was achieved in 2 4 of 29 subjects of the first three groups. The more pronounced decay of HI V-DNA (half life 28 weeks) up to < 50 HIV-DNA copies/10(6) CD4+ cells was d etected in patients of group 1. At the year's endpoint, five patients (four in group 1 and one in group 2) had < 20 HIV-DNA copies. However, HIV strai ns sensitive to antiretroviral drugs were isolated from peripheral lymphocy tes of 16 out of 34 patients. Conclusion: In patients with undetectable plasma viraemia after 1 year of H AART, the highest reduction of proviral DNA up to < 50 copies/10(6) CD4+ ce lls was obtained only in subjects in the early asymptomatic phase of infect ion. Nevertheless, a replication-competent virus can be detected in all pha ses of antiretroviral therapy. (C) 2000 Lippincott Williams & Wilkins.