Highly active antiretroviral therapy (HAART) of HIV-infected people results in viral control. When HAART is interrupted, however, HIV-infected individuals lose viral control and show reappearance of plasma viremia. Thus, they need to continue HAART almost forever for prevention of AIDS progression. Cytotoxic T lymphocyte (CTL) responses play an important role in viral suppression but are mostly reduced during HAART. There have been many attempts to develop therapeutic vaccines inducing CTL responses during HAART toward better control, although none of them has yet shown sufficient efficacy.