A woman in the New York City area appears to have been cured of an HIV infection using a cutting-edge stem cell transplant method, making her the first woman to possibly be cured of the virus.
Now described as "asymptomatic and healthy", the woman has joined a small group of people - including three men - whom scientists have cured, or very likely cured, of the highly resilient human immunodeficiency virus. Researchers are also aware of extraordinary cases where the immune systems of two women appeared to suppress the virus without medication.
As part of a study funded by the National Institutes of Health, the 'New York patient' - who is middle-aged and mixed race - received a transplant of stem cells with a rare genetic mutation that blocks HIV invasion. She received her transplant at New York-Presbyterian Weill Cornell Medical Center in August 2017, the same year she was diagnosed with leukaemia - a cancer of blood-forming tissues, including bone marrow - and four years after she had been diagnosed with HIV in 2013.
According to local reports, the woman has exhibited no detectable signs of HIV in extensive testing since she stopped taking her medication in October 2020.
Her doctors said they consider the woman's HIV to be in long-term remission, suggesting she could possibly be cured of the virus. Unlike people who have HIV but maintain their health with ongoing drug treatment, the woman - if cured - will have no replicable traces of the virus in her body.
"Everything is looking very promising," said Dr Marshall Glesby, associate chief of the division of infectious diseases at Weill Cornell Medicine and New York-Presbyterian, who is treating the woman. The details of her case were presented on Tuesday (local time) at the Conference on Retroviruses and Opportunistic Infections, which is being held virtually.
Four years ago, the woman received a transplant of stem cells from an adult relative and umbilical-cord blood from an unrelated newborn. Cord-blood transplants take as long as 30 days to graft.
Dr Glesby and other researchers said the treatment is expected to be suitable for a broader range of patients compared to the transplants used to treat HIV in the three others, as umbilical-cord blood doesn't have to be a precise genetic match to the receiving patient.
In the first case of what was ultimately classed as a successful HIV cure, researchers treated American man Timothy Ray Brown, initially called the 'Berlin patient', for acute myeloid leukaemia (AML). He received a stem cell transplant from a donor who had a rare genetic abnormality that provides the immune cells targeted by HIV with a natural resistance to the virus. The method, which was first made public in 2008, has since reportedly cured HIV in two other patients - a man in London and a man in Düsseldorf, Germany - but has also failed in a number of others. Brown died in 2020 following a relapse of leukaemia.
As reported by NBC News, the process is designed to replace a HIV-infected patient's immune system with that of another person, treating their cancer while also curing their HIV. The original immune system is destroyed with chemotherapy and sometimes irradiation. Then - as long as the transplanted HIV-resistant stem cells engraft properly - new viral copies that may potentially emerge from any remaining infected cells will be unable to infect other immune cells.
However, experts say it is unethical to attempt to cure HIV through the sometimes fatal stem cell transplant in patients who do not also have a potentially fatal cancer or other condition.
Dr Deborah Persaud, a paediatric infectious disease specialist at the Johns Hopkins University School of Medicine who chairs the NIH-funded scientific committee behind the new case study, said that while researchers are "very excited" about the new case of a possible cure, the method is "still not a feasible strategy for all but a handful of the millions of people living with HIV".
Carl Dieffenbach, director of the Division of AIDS at the National Institute of Allergy and Infectious Diseases, told NBC News that another apparent success in curing HIV "continues to provide hope" to other sufferers.
"It's important that there continues to be success along this line," he said.
Numerous ultrasensitive tests have been unable to detect any sign of HIV capable of replicating in the woman's immune cells. They also drew immune cells from the patient and in a laboratory experiment, attempted to infect them with HIV - but it didn't work.
According to reports, the woman's transplant engrafted well and she has been in remission from her leukaemia for more than four years. Her HIV treatment was discontinued in 2020 and more than a year later, the virus has yet to return.
Researchers estimate there are approximately 50 patients per year in the US who could benefit from the procedure, with the ability to use partially matched umbilical cord blood grafts greatly increasing the likelihood of finding suitable donors.