HIV Remission Achieved After Rare Bone Marrow Transplant

Rare Sibling Stem Cell Transplant Leads to HIV Remission for ‘Oslo Patient’

A 63-year-old Norwegian man, referred to as the “Oslo patient,” has achieved long-term remission from HIV following a stem cell transplant from his brother. The case, detailed in a study published in the journal Nature Microbiology on April 13, 2026, marks a rare instance where a patient has seen the virus effectively cleared from their system.

The patient, who was first diagnosed with HIV in 2006 at the age of 44, underwent an allogeneic hematopoietic stem cell transplantation (HSCT) at age 58. While the procedure was primarily intended to treat a rare form of blood cancer, it resulted in the unexpected elimination of the virus.

The success of the treatment is attributed to a rare genetic mutation carried by the patient’s brother. The donor possessed the CCR5Δ32/Δ32 mutation, which disables a specific protein on the surface of immune cells that HIV typically exploits to trigger an infection. By lacking these receptor proteins, the donated cells were effectively “locked” against the virus.

Researchers from Oslo University Hospital tracked the patient’s progress through “chimerism,” monitoring how the donated cells replaced the patient’s own immune system in the blood, bone marrow, and gut tissues. This genetic shift provided a critical barrier that prevented the virus from rebounding.

Clinical findings indicate a high level of success in the remission process:

• Medication Cessation: The patient was able to stop taking antiretroviral medication 24 months after the transplant.
• Viral Absence: Five years after the HSCT, there has been no evidence of viral rebound.
• Cellular Analysis: A comprehensive review of more than 65 million immune system cells revealed no virus capable of multiplying and no detectable HIV-specific T-cell responses.
• Tissue Samples: Samples from the gut and blood taken two years post-transplant showed no HIV DNA integrated into the host DNA.
• Antibody Decline: Researchers observed a gradual decline in HIV antibody levels over a four-year period.

This case is exceptionally rare due to the biological odds involved. In northern European populations, the frequency of the CCR5Δ32/Δ32 mutation is approximately 1%, and there is only a 25% probability that a sibling will be a compatible match for a transplant.

The “Oslo patient” is now one of only a handful of individuals—potentially only the tenth person globally—to achieve this level of remission. Because HIV typically remains hidden in cellular pockets and rebounds once medication stops, these rare cases provide invaluable data for scientists.

According to the researchers, the findings contribute essential evidence to the existing knowledge base regarding HIV cures. The study enhances the medical community’s understanding of HIV pathology, molecular mechanisms, and predictive biomarkers, which may eventually inform broader treatment strategies beyond stem cell transplantation.