An adult man in Norway has achieved long-term HIV remission after receiving an allogeneic hematopoietic stem cell transplant (HSCT) from his brother, joining a small group of patients worldwide who appear to be functionally cured. The 63-year-old “Oslo patient” was documented as being in remission five years after HSCT to treat myelodysplastic syndrome. Tests of blood, gut, and bone marrow found no detectable viral reservoirs, and his case is reported in Nature Microbiology. This is the first recorded instance of HIV remission after a stem cell donation from a sibling.
Most documented HIV remissions after HSCT have involved donors carrying the CCR5Δ32 mutation. CCR5 is a receptor HIV commonly uses to enter immune cells; the CCR5Δ32 mutation prevents expression of that receptor, blocking many strains of HIV. The Oslo patient received stem cells from a sibling homozygous for CCR5Δ32, a trait believed to be central to achieving durable remission. The mutation is rare and more common in some European populations.
Experts say this case adds to an evolving understanding of how HSCT can eliminate HIV reservoirs. Steven Deeks, MD, noted there have been multiple successful transplants and that each contributes to learning about mechanisms of cure. Augusto Dulanto, MD, described the case as “a cause for optimism.” Marshall Glesby, MD, PhD, emphasized that while CCR5Δ32 and other effects are key, multiple factors likely contribute.
HSCT involves ablating much of a patient’s bone marrow and immune system with chemotherapy or radiation, then infusing donor stem cells to rebuild immunity. This can drastically reduce the number of cells harboring latent HIV—viral reservoirs that enable viral rebound if antiretroviral therapy (ART) is stopped. When donor cells carry homozygous CCR5Δ32, the new immune system is resistant to common HIV-1 strains, increasing the chance that remaining virus cannot reestablish infection.
Not all remission cases rely on CCR5Δ32. Some patients have reached remission after receiving donor cells without the mutation. Researchers point to graft-versus-host disease (GVHD) and a “graft-versus-reservoir” effect as potential contributors: as the donor immune system establishes itself, it can attack residual host cells, possibly eliminating cells that hide latent virus. Drugs used to prevent or treat GVHD—such as ruxolitinib and vedolizumab—may also have anti-HIV effects. Combined with ART during recovery, these factors may create conditions that reduce the reservoir to levels at which rebound no longer occurs.
Other well-known cases of HIV remission after HSCT include patients in Berlin, London, and New York; in each, HSCT was performed to treat a hematologic condition, and HIV remission followed incidentally. The Geneva case is an example where remission occurred without a CCR5Δ32-positive donor, supporting the idea that multiple mechanisms can lead to cure.
Despite its significance for understanding HIV biology, HSCT is not a practical cure for most people with HIV. The procedure carries high risks, including a 10–20% mortality rate within the first year and substantial risk of cancer relapse among transplant recipients. Given these dangers, HSCT is typically only considered when it is clinically indicated for another serious condition, such as a hematologic malignancy, where it may simultaneously treat both conditions.
By contrast, modern ART suppresses HIV to undetectable levels and is safe and accessible for long-term management, though it is not a cure and requires lifelong treatment for most patients. Persistent immune activation and inflammation in people living with HIV can contribute to comorbidities even when the virus is well controlled.
Researchers continue to study rare HSCT remission cases to clarify the roles of genetics, immune responses, GVHD, and adjunctive drugs in eliminating viral reservoirs. Insights from these cases guide efforts to develop scalable strategies for long-term remission or cure that do not rely on risky transplants, with the broader goals of reducing treatment burden and improving long-term health for people living with HIV.
