Oslo patient shows long term hiv remission after stem cell transplant

15:00

By: Dakir Madiha

Oslo patient shows long term hiv remission after stem cell transplant

A 63 year old Norwegian man known as the “Oslo patient” has achieved prolonged remission from HIV after receiving a stem cell transplant from his brother, according to findings published in the journal Nature Microbiology.

The patient was diagnosed with HIV in 2006 and began antiretroviral therapy in 2010, which kept the virus under control. In 2018, he developed myelodysplastic syndrome, a serious bone marrow cancer. After the disease relapsed despite treatment, doctors at Oslo University Hospital opted for a bone marrow transplant.

The medical team initially searched for an unrelated donor carrying the CCR5 delta 32 mutation, a rare genetic variant known to block HIV from entering immune cells. No match was found. The patient’s brother was selected as a donor to treat the cancer, and only on the day of the transplant did doctors discover he carried two copies of the protective mutation.

Researchers said siblings have a 25 percent chance of being compatible donors, while the CCR5Δ32 mutation appears in about 1 percent of Northern European populations. The case was described by hematologist Anders Eivind Myhre and co author Marius Trøseid in comments to Live Science.

Two years after the transplant, donor cells had fully replaced the patient’s immune system in his blood, bone marrow, and gut. He stopped antiretroviral therapy, and five years later, no viral rebound has been detected.

Scientists examined 65 million CD4 T cells, the main targets of HIV, and found no trace of replication capable virus. The patient’s immune system responded normally to common infections such as influenza but showed no recognition of HIV, suggesting it had no prior exposure.

Researchers caution that the procedure is not a scalable cure. Bone marrow transplants carry a 10 to 20 percent mortality risk in the first year and are reserved for life threatening conditions such as cancer. The Oslo patient developed graft versus host disease, a severe complication, but recovered.

Experts describe the case as another step toward a functional cure. Ongoing research into modified antibodies and other therapies may eventually allow broader groups of patients to live without daily treatment.