The present study assessed the long-term clinical follow-up of 26 of 60 human immunodeficiency virus (HIV)-positive patients who followed structured treatment interruption (STI) protocols and who, because of good virological response, did not resume receipt of highly active antiretroviral therapy (HAART). The plasma viral load (pVL) noted after > or =2 years without antiretroviral therapy remained significantly lower than the pVL noted before initiation of HAART, for 11 of the 26 patients (i.e., for 18% of the 60 patients who had STI performed). The CD4+ T cell count remained stable throughout the study. A low pVL at the end of follow-up was independently associated with a low CD8+CD38+ T lymphocyte count and a high stimulation index to p24 antigen after STI. In conclusion, approximately 2 years after STI, only a low proportion of patients who had a good immunological profile at the end of the STI period still had a good virological response.