The AELIX-002 Phase 1 study will evaluate the safety and immunogenicity of both the DNA.HTI and MVA.HTI vaccines in HIV-1 positive patients on suppressive antiretroviral treatment who started cART within first 6 months of confirmed HIV-1 acquisition. Patients will be randomized to receive active vaccine or placebo in a double blinded fashion. There will be a sentinel group of three patients; two will receive active vaccine and one will receive placebo (0.9% normal saline). During the sentinel phase of the study only one patient will be enrolled per day. Two weeks later and in the absence of any related SAE or ≥ Grade 3 adverse event lasting >72h after vaccination in any of the 3 sentinel individuals, six of the remaining cohort will be enrolled (in blocks of 3 patients per day) and the final six patients one week later, also in blocks of 3 patients per day. On each vaccination day, 2 patients will receive active IMP and 1 will receive placebo (2:1).