Virologic determinants of success after structured treatment interruptions of antiretrovirals in acute HIV-1 infection.

Infectious Diseases Unit, Alfred Hospital, Melbourne, Australia.
JAIDS Journal of Acquired Immune Deficiency Syndromes (Impact Factor: 4.39). 03/2008; 47(2):140-47. DOI: 10.1097/QAI.0b013e31815dbf7f
Source: PubMed

ABSTRACT Latently infected resting memory CD4 T cells are thought to be the major reservoir that contributes to rebound viremia after cessation of antiretrovirals (ARVs). Commencing ARVs during primary HIV-1 infection (PHI) may limit the size of the latent pool and lead to improved control of viral replication during structured treatment interruption (STI).
Individuals with PHI (n = 59) were randomized to receive ARVs with or without hydroxyurea. After STI, a good response was defined as maintenance of HIV-1 RNA <5000 copies/mL for 24 weeks off therapy. In a detailed prospective virologic substudy (n = 19), integrated HIV-1 DNA, total HIV-1 DNA, and cell-associated HIV-1 unspliced (US) RNA were quantified using a real-time polymerase chain reaction assay.
The plasma HIV-1 RNA 12 weeks after the initiation of ARVs was significantly lower in good responders (n = 7) compared with poor responders (n = 12) (P = 0.005). There were no significant differences between good and poor responders in integrated HIV-1 DNA, HIV-1 DNA, and HIV-1 US RNA. Integrated HIV-1 DNA before initiation of ARVs was strongly correlated with plasma HIV-1 RNA at week 12 (P = 0.006, r = 0.81).
HIV-1 RNA measured 12 weeks after initiation of ARV was the only virologic variable associated with viral rebound after treatment interruption in PHI.

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