In a remarkable breakthrough that may redefine the future of HIV treatment, researchers at Gladstone Institutes have uncovered new molecular mechanisms that could allow people living with HIV to maintain long-term remission without the need for daily antiretroviral therapy (ART). Their work has identified two genes that operate within infected immune cells to effectively “lock” the HIV virus into a dormant state, preventing its reactivation—a feat that has eluded scientists for decades. Even more promising, they discovered that metformin, a widely prescribed and affordable diabetes medication, can activate one of these gene-controlled locks, potentially offering a transformative avenue for HIV management.
Antiretroviral therapy has been the cornerstone of HIV treatment, successfully suppressing viral replication and enabling patients to lead healthier lives. However, ART is not a cure: within the body, reservoirs of immune cells harbor latent virus, poised to rekindle infection as soon as treatment is interrupted. For most patients, stopping ART results in viral rebound within weeks, which can rapidly undermine the immune system and lead to AIDS. Yet intriguingly, a rare subset of individuals exhibits a slow or absent rebound, maintaining control over the virus without medication for prolonged periods. Understanding the biological underpinnings of this phenomenon has been an urgent challenge for researchers seeking a functional cure.
Gladstone’s team, led by senior investigator Nadia Roan, PhD, embarked on a comprehensive multiomic analysis using samples from 75 participants across four clinical trials. These patients intentionally halted ART as part of experimental protocols, allowing scientists to closely monitor the timing and dynamics of HIV rebound. By profiling gene and protein expression in multiple immune cell subsets harvested immediately prior to treatment interruption, Roan’s group sought the cellular factors correlated with delayed viral resurgence. Their meticulous work revealed a compelling association between specific immune phenotypes and extended viral suppression.
One of the standout findings involves stem cell memory CD8+ T cells, a rare subset of immune cells with remarkable longevity and self-renewing capabilities. Participants exhibiting higher levels of these cells tended to experience significantly delayed HIV rebound, with the longest cases extending over 33 weeks. These “stem-like” CD8+ T cells appear to continuously regenerate, maintaining sustained antiviral activity that could stave off viral awakening. This discovery underscores the potential of harnessing immune memory and durability to achieve ART-free viral control.
In addition to CD8+ T cells, the researchers observed that a nonconventional subset of natural killer cells also correlated with postponed viral rebound. Traditionally recognized for their role in destroying infected cells, these natural killer cells may also modulate the immune environment in ways that suppress HIV reactivation. These insights highlight the complexity and heterogeneity of immune cell contributions to HIV control, suggesting that multiple immune pathways can be leveraged to maintain remission.
Crucially, the study pinpointed two cellular genes, DDIT4 and ZNF254, whose elevated expression in CD4+ T cells—the primary HIV reservoir—linked to extended viral suppression. Follow-up laboratory experiments confirmed that both genes function as intrinsic “security locks,” inhibiting HIV transcription and preventing the virus from emerging from latency. This finding lays the groundwork for a “block and lock” strategy, wherein therapeutics would first block viral activation and then enforce a durable lock that silences HIV permanently.
Of the two genes, DDIT4 holds particular promise due to its druggability. Previous research indicated that the diabetes drug metformin can boost DDIT4 expression in non-immune cells, and Roan’s study confirmed this effect occurs in T cells as well. Treating HIV-infected cells in vitro with metformin successfully suppressed HIV reactivation, suggesting the drug could serve as an accessible, safe, and cost-effective adjunct to existing ART by enforcing viral latency. This drug repurposing opens a fast track to clinical evaluation since metformin’s safety profile is well-characterized.
The implications of these findings are profound. Moving beyond viral suppression, the “block and lock” approach strives for durable remission, transforming HIV from a chronic illness requiring lifelong medication into a manageable condition with reduced treatment burden. Furthermore, silencing residual viral gene expression may alleviate chronic inflammation—a key driver of comorbidities in people living with HIV, even those on effective ART—thereby improving overall health outcomes.
Gladstone’s investigation was bolstered by collaboration with multiple academic institutions and cutting-edge analytical techniques, including high-dimensional gene and protein profiling of immune cells. Moreover, public data from elite controllers—rare individuals who suppress HIV without therapy from the outset—show higher levels of ZNF254, reinforcing the gene’s potential role in natural immune-mediated viral control. The concept of engineering or delivering these genes to enhance patients’ immune cells evokes an exciting frontier in HIV cure research, intersecting with gene therapy and synthetic biology.
Moving forward, Roan and collaborators plan to evaluate metformin and related compounds in diverse preclinical models to assess their efficacy in preventing HIV rebound when ART is interrupted. They anticipate this work will pave the way for clinical trials testing metformin not only as a latency-promoting agent but also as a tool to reduce chronic immune activation. The convergence of immunology, genetics, and pharmacology embodied in this study epitomizes the innovative approaches necessary to surmount the formidable challenges of HIV persistence.
This landmark study amplifies hope for a future where HIV treatment transcends daily pill regimens, embracing strategies that empower the immune system and pharmacology to achieve sustained remission and improved quality of life. By illuminating the “locks” that keep HIV asleep, and identifying a readily available drug capable of turning these locks, Gladstone Institutes’ research marks a pivotal step on the path to functional HIV cure.
Subject of Research: HIV reservoirs and immunological mechanisms controlling viral rebound
Article Title: Multiomic analysis of ART-interruption cohorts identifies cell-extrinsic and -intrinsic mechanisms driving lymphocyte-mediated control of HIV rebound
News Publication Date: March 20, 2026
Web References: http://dx.doi.org/10.1016/j.immuni.2026.01.029
References: Ma T, George A, Li Z, et al. Immunity, 2026.
Image Credits: Michael Short/Gladstone Institutes
Keywords: HIV, antiretroviral therapy, viral rebound, immune cells, CD8+ T cells, natural killer cells, gene expression, DDIT4, ZNF254, metformin, block-and-lock strategy, HIV cure research
