Analytical treatment interruption: detection of an increase in the latent, inducible HIV-1 reservoir more than a decade after viral resuppression

Despite the success of antiretroviral therapy (ART) in suppressing HIV-1 replication, viral reservoirs persist and reignite viremia upon treatment interruption, posing a major barrier to achieving a cure. Analytical treatment interruption (ATI) is a key experimental strategy in HIV-1 cure research, used to evaluate the efficacy of novel therapeutic interventions. While ATI protocols have evolved to minimize clinical risks, the long-term consequences of ATI remain poorly understood. Here, we investigated the enduring immunologic and virologic effects of extended ATI in a unique cohort of volunteers enrolled in a dendritic cell-based therapeutic vaccine trial (DC-TRN) nearly two decades ago. Participants were re-evaluated more than 10 years after ART resumption. Using integrated approaches--including proviral reservoir quantification, inducibility profiling and high-dimensional immune phenotyping--we identified a significant expansion of the inducible HIV-1 reservoir and a distinct immune signature, despite sustained viral suppression and clinical stability. Notably, Central Memory T cells expressing CXCR3 positively correlated with inducible tat/rev msRNA+ T cells. These findings underscore the durable imprint of ATI-based immune interventions on HIV-1 reservoir dynamics and immune homeostasis. Overall, the findings emphasize the need for extended follow-up and functional immune assessments in HIV-1 cure-focused trials.