Originally published 2022-02-20.
In February 2022 researchers reported that a middle-aged American woman appeared to have been cured of HIV after a stem-cell transplant. She had the transplant to treat leukaemia, and it used cells from umbilical cord blood. At the time she had been free of detectable HIV for 14 months without taking antiretroviral drugs. She became known as the "New York patient", the first woman and the first person of mixed race reported to reach long-term HIV remission this way.
The key point for anyone living with HIV is that this was not a treatment for HIV alone. It was a risky cancer procedure, used only because she needed a transplant anyway. Daily antiretroviral therapy remains the standard care, and it lets people with HIV live long, healthy lives.
What happened in this case
Doctors first described the case at the Conference on Retroviruses and Opportunistic Infections (CROI) in Denver. It was later published in the journal Cell in 2023. According to Johns Hopkins Medicine, the woman had her transplant in 2017, and it put both her leukaemia and her HIV into remission.
The procedure is called a haploidentical-cord, or "haplo-cord", transplant. She received two infusions. One was umbilical cord blood stem cells carrying a genetic trait that makes them resistant to HIV. The other was cells from a partly matched adult donor, which helped her blood system recover while the cord cells took hold. When the full report came out, more than four and a half years had passed since the transplant, and she had tested HIV negative for 18 months after stopping treatment. The researchers described her as likely cured.
The work was part of a US study co-led by Dr Yvonne Bryson of the University of California, Los Angeles, and Dr Deborah Persaud of Johns Hopkins. It follows people with both HIV and cancers that need a stem-cell transplant, and around 25 participants were expected to take part.
Why some cells resist HIV
HIV infects immune cells called CD4 T cells. To get inside, most strains latch onto a receptor on the cell surface called CCR5. A small share of people, mostly of northern European ancestry, inherit two copies of a gene variant known as CCR5-delta32, and their cells lack a working CCR5 receptor. Those strains of HIV cannot get in.
A stem-cell transplant replaces a person's blood and immune system with the donor's. If the donor carries two copies of CCR5-delta32, the new immune cells are resistant to the virus. Over time the patient's original infected cells are replaced, so the virus has nowhere to hide and grow.
Why cord blood matters
Earlier cures used adult bone marrow or stem cells from donors with the protective variant. Finding such a donor who is also a close tissue match is very hard. It is even harder for people of mixed or non-European ancestry, because both the variant and many tissue types are less common in donor registries.
Cord blood offers a way around this. Cord blood transplants generally do not need as close a match as adult transplants, and cord blood banks can be screened for the delta32 variant. The drawback is quantity: a single cord unit holds relatively few cells. That is why the doctors combined it with adult donor cells. Researchers hoped this approach would widen the pool of people who could benefit, especially women and people of colour, who are under-represented in HIV cure research.
Dr Steven Deeks, an HIV specialist at the University of California, San Francisco, told The New York Times in 2022: "The fact that she's mixed race, and that she's a woman, that is really important scientifically and really important in terms of the community impact."
The earlier patients
The New York patient joined a very small group:
- The Berlin patient, Timothy Ray Brown, had a stem-cell transplant in Berlin in 2007, repeated in 2008, to treat acute myeloid leukaemia. His donor carried two copies of CCR5-delta32. He stayed free of HIV until he died of a return of his leukaemia in September 2020, aged 54.
- The London patient, Adam Castillejo, was announced in 2019. He received a bone marrow transplant for Hodgkin lymphoma, also from a donor with the protective variant.
When the full findings were published in 2023, Johns Hopkins described the woman as the fourth person in remission and likely cured through this type of transplant. A handful of similar cases have been reported since. All of them involved people who needed a transplant to treat cancer.
Why this is not a cure for most people
Stem-cell transplants are among the hardest treatments in medicine. Patients first get chemotherapy, and sometimes radiation, to wipe out their own bone marrow. They then face weeks of high infection risk and possible graft-versus-host disease, where the donor's immune cells attack the body. Some people die from the procedure. Doctors would not put someone through this just to treat HIV, because modern drugs control the virus so well.
That is the real story behind the headlines. According to the World Health Organization, there is still no cure for HIV infection, but effective treatment turns it into a manageable long-term condition. People on treatment whose virus is suppressed do not pass HIV to their sexual partners. In 2025, the WHO says, 95% of people on treatment had a suppressed viral load.
The value of cases like this lies in what they teach. They show that the virus's hiding places in the body can be cleared. That points researchers toward safer strategies, such as gene therapies that edit a person's own cells to remove CCR5, and treatments that flush out and destroy dormant virus.
HIV in numbers
AIDS was first recognised in 1981, and HIV has since become one of the deadliest epidemics in modern history. The WHO estimates it has claimed about 44 million lives so far. About 41 million people were living with HIV at the end of 2025, nearly two-thirds of them in Africa, and around 570,000 people died of HIV-related causes that year. Without treatment, HIV gradually destroys the immune system and leads to AIDS, which leaves people open to infections and cancers that a healthy body would fight off.
Anyone who thinks they may have been exposed to HIV, or who has questions about treatment, should talk to a doctor or a sexual health clinic. Testing is quick and widely available, and starting treatment early makes a large difference.
Sources: Johns Hopkins Medicine, 10 April 2023; Wikipedia: Timothy Ray Brown; World Health Organization: HIV and AIDS fact sheet.
COMMENTS