The present invention relates to an in vitro method of screening for candidate compounds capable of being used for the preventative and/or curative treatment of a disease caused by a retrovirus in which the candidate compound which modulates the expression and/or the activity of the SAMHD1 protein is identified as a candidate compound capable of being used for the preventative and/or curative treatment of a disease caused by a retrovirus.The invention also relates to a vaccine composition and an immunogenic composition, comprising i) an inhibitor of the expression and/or of the activity of the SAMHD1 protein and ii) at least one antigen of a retrovirus.
