“Oslo Patient” Achieves Sustained HIV Remission After High-Risk Stem Cell Transplant
A 63-year-old Norwegian man has remained HIV-free for five years after a stem cell transplant from his brother, offering new insights for cure research.
The Case Overview
A 63-year-old Norwegian man, referred to as the "Oslo patient," has achieved sustained remission from HIV after receiving a stem cell transplant from his brother to treat a rare blood cancer. The case, documented by researchers from Oslo University Hospital and published in the journal Nature Microbiology, offers further insights into potential pathways for HIV cure research, though the procedure is considered high-risk and not a viable treatment for the general population.
Patient Medical History and Procedure
The patient was diagnosed with HIV in 2006 and began antiretroviral therapy (ART) in 2010, achieving viral suppression. In 2018, he was diagnosed with myelodysplastic syndrome, a type of bone marrow cancer. After initial treatment and relapse, he received an allogeneic hematopoietic stem cell transplant (HSCT) at Oslo University Hospital.
The medical team initially searched for an unrelated donor with the CCR5Δ32/Δ32 genetic mutation but was unsuccessful. The patient's brother was selected as the donor to treat the cancer, with his CCR5 status unknown prior to the procedure. It was later discovered that the donor carried two copies of the CCR5Δ32/Δ32 mutation, which removes the CCR5 receptor on white blood cells that HIV typically uses to enter cells.
Medical Outcomes and Detection
Two years after the transplant, analysis confirmed that the donor-derived cells had completely replaced the patient's original immune cells in the blood, bone marrow, and gut tissue. The patient ceased ART 24 months post-transplant. At five years post-transplant, no viral rebound has been detected.
Extensive testing of approximately 65 million CD4 T cells found no replication-competent HIV. Analysis of lymph tissue in the gastrointestinal tract, a known reservoir for dormant HIV, also showed no functioning HIV DNA. While some HIV fragments remained, they were not in a functional state.
Researchers observed a decline in HIV antibodies and noted that T cells stopped responding to HIV. Laboratory tests indicated that the new immune cells responded to common viruses but did not recognize HIV.
Researcher Statements and Analysis
In the published paper, researchers stated: "The case of the Oslo patient contributes valuable evidence to the existing knowledge base regarding HIV cure cases." They added that such studies "enhance our understanding of HIV pathology, molecular mechanisms, and predictive biomarkers that may be of broader interest, extending beyond patients treated with allogeneic HSCT."
Regarding the immune response, researchers wrote: "The absence of HIV-specific T cell responses in our data supports the hypothesis that such an absence correlates with sustained HIV remission. "
Study co-author Dr. Marius Trøseid stated the case represents a "likely cure," though the scientific community often uses the term "sustained remission." Dr. Anders Eivind Myhre, another co-author, noted the statistical improbability of the scenario, citing a 25% probability of a sibling being a transplant match and the frequency of the CCR5Δ32/Δ32 genotype at approximately 1% in northern European populations.
The patient experienced graft-versus-host disease after the transplant, a severe immune reaction, which was treated with immune-modulating medication. Researchers noted that this immune reaction and the drugs used to manage it may have contributed to the elimination of HIV.
Context and Limitations
Bone marrow stem cell transplants carry significant risks, including rebooting the immune system and leaving patients vulnerable to infection. Researchers note that approximately 10-20% of individuals who undergo these transplants die within a year. The procedure is performed only as a last resort for life-threatening conditions like certain cancers and is not considered a viable or practical option for a widespread HIV cure.
Similar cases of HIV remission following stem cell transplants from donors with the CCR5Δ32/Δ32 mutation have been recorded previously, although they are rare. Some recent cases have reported remission without the mutation or with only one copy.
Future Research Directions
The research team expressed interest in analyzing data from all known HIV "cure" cases. They wrote: "Moving forward, a critical step will be to compare existing cases of HIV cure to identify the most effective combination of biomarkers." They proposed "conducting individual patient data meta-analyses as a logical next step, ideally followed by prospective sampling and new analyses that apply harmonized protocols in centralized laboratories."
Researchers noted that the testing methodology used in this case could serve as a benchmark for evaluating future transplant patients. Other strategies, such as engineered antibodies and approaches being investigated by international consortia like EU2Cure, are being explored as potential alternatives for broader HIV control.