title: Longitudinal changes in HIV-specific IFN-gamma secretion in subjects who received Remune vaccination prior to treatment interruption.
abstract: BACKGROUND
  Despite the benefits of highly active antiretroviral therapy (HAART) for suppressing viral replication in HIV infection, virus persists and rebounds during treatment interruption (TI). This study explored whether HAART intensification with Remune vaccination before TI can boost HIV-1-specific immunity, leading to improved control of viremia off HAART.
  
  
  METHODS
  Ten chronically HIV-infected adults were enrolled in this proof of concept study. After a 6-month HAART intensification phase with didanosine, hydroxyurea, granulocyte-macrophage colony-stimulating factor, (GM-CSF), and a first dose of Remune (HIV-1 Immunogen), HAART was discontinued. Patients continued to receive Remune every 3 months until the end of study. HAART was restarted if viral load did not fall below 50,000 copies/ml of plasma within 3 months or if CD4+ counts decreased to <200 cells/mm3. HIV-specific immunity was monitored with the interferon-gamma (IFN-gamma) ELISPOT assay.
  
  
  RESULTS
  All subjects experienced viral rebound during TIs. Although the magnitude and breadth of HIV-specific responses to HLA-restricted optimal peptide panels and Gag p55 peptide pools increased and viral load decreased by 0.44 log10 units from TI#1 to TI#2, no significant correlations between these parameters were observed. The patients spent 50.4% of their 36 months follow up off HAART.
  
  
  CONCLUSIONS
  Stopping HAART in this vaccinated population induced immune responses that persisted after therapy was restarted. Induction of HIV-specific immunity beyond IFN-gamma secretion may be contributing to better control of viremia during subsequent TIs allowing for long periods off HAART.
authors.affiliation: McGill University Health Centre, Montreal, Quebec, Canada. kenneth.huang@mail.mcgill.ca
authors.forename: Kenneth H
authors.initials: KH
authors.lastname: Huang
authors.forename: Marie-Pierre
authors.initials: MP
authors.lastname: Boisvert
authors.forename: Famane
authors.initials: F
authors.lastname: Chung
authors.forename: Maude
authors.initials: M
authors.lastname: Loignon
authors.forename: Don
authors.initials: D
authors.lastname: Zarowny
authors.forename: Lise
authors.initials: L
authors.lastname: Cyr
authors.forename: Emil
authors.initials: E
authors.lastname: Toma
authors.forename: Nicole F
authors.initials: NF
authors.lastname: Bernard