In this study, HIV-1 infected subjects on ART, with undetectable HIV-1 viral load, will be immunized with 1mg TUTI-16 or placebo in a randomized double blind fashion (prime and 3 week boost). Three weeks after the 3 week boost (week 6) ART will be stopped. HIV-1 viral load and CD4+ T-cell levels will be determined at defined intervals through 54 weeks (48 weeks Post ART discontinuation).