HIV-1 infected patients with normal peripheral blood CD4+ T-cell counts and undetectable viral load will be recruited in four Belgian HIV reference centers. Selected patients will undergo a two-step screening in which a viral reservoir measurement will be performed and among those with a very low viral reservoir an analytical treatment interruption of their longstanding antiretroviral therapy (ART). There is no randomization foreseen. Patients will receive an intense clinical and laboratory follow-up during 48 weeks followed by 12 weeks post intervention.