Concomitant administration of recombinant human growth hormone (rhGH) may boost the expansion of immune reconstitution and broaden specific T cell responses not achievable by vaccination alone. The main objective of that study is to test the validity of this hypothesis with vaccines which are routinely administered to HIV-1 patients(tetanus toxoid and hepatitis A virus vaccines) in order to, if proven of value, use this strategy of HIV vaccination in the near future. This is a pilot, randomized, clinical open label study aimed to investigate thymic functionality and the HIV-specific responses after administration of rhGH in HIV-1 infected patients in highly active antiretroviral therapy (HAART) regimen.