Patients will be monitored according to the international and local guidelines for HIV infection as far as timing and type of laboratory and clinical controls. Laboratory exams will be decided locally and only a few key tests are required for the study. The timing of laboratory evaluation will be 1 and 2 months after each treatment interruption and thereafter every 2 months in the STI arm and every 4 months in the control group. All data will be stored in a computerized data-base.