A middle-aged, mixed-race woman is the third patient to be potentially cured of HIV, with the virus in long-term remission four years after she received a transplant of stem cells harvested from an infant’s umbilical cord blood, scientists said Tuesday.
In 2009, scientists first reported that a White man with leukemia, originally known to the world only as the “Berlin patient,” had been possibly cured of HIV with a transplant of stem cells resistant to HIV. A decade later, the approach was used in the “London patient,” a Hispanic man with Hodgkin’s lymphoma. A man in Dusseldorf, Germany, was reported to be in HIV remission after a transplant in 2019, but he was not counted by the research team as a previously cured patient.
One-off reports of long-term HIV remission have inspired hope and reignited the search for an HIV cure, but they also come with inherent limitations. All of the patients, including the middle-aged woman, who was treated by doctors at Weill Cornell Medicine in New York, received the transplant as part of treatment for cancer.
The “Berlin patient,” later revealed to be Timothy Ray Brown, eventually died — when his leukemia, not his HIV, rebounded. Stem cell transplants are not likely to be widely used as a treatment for otherwise healthy people living with HIV.
“This is critical science to eventually get us to a cure,” said Carlos del Rio, professor of medicine at Emory University School of Medicine. “This is not a scalable intervention. The way I think about this: This is like sending someone on a rocket to the moon. It’s great science, but it’s not the way we’re going to travel.”
The patient, who has not been publicly identified, was diagnosed with HIV in 2013. Four years later, she developed high-risk acute myeloid leukemia and received the stem cell transplant as a treatment for both diseases.
The transplanted stem cells were different from those used in previous cases. Those cases depended on stem cells from adults, and they are harder to match with a recipient.
The woman received a “haplo/cord transplant” that included a mixture of stem cells from a relative and stem cells from an infant’s umbilical cord. The infant stem cells contained a naturally occurring, but rare, feature that made them resistant to HIV. They possessed a deletion in the CCR5 gene that made it impossible for the virus to infect cells. That deletion usually occurs in people of Northern European or Caucasian descent.
The patient stopped taking the antiretroviral drugs that kept her HIV in check 14 months ago, and there has been no rebound of the virus.
The level of virus in her blood was “undetectable through this whole period,” said Yvonne J. Bryson, an infectious-diseases physician at the David Geffen School of Medicine at the University of California at Los Angeles, who presented the case.
“This provides hope for the use of cord blood cells … to achieve HIV remission for individuals requiring transplant for other diseases,” Bryson said. “This provides additional proof that HIV reservoirs can be cleared sufficiently to afford remission and cure.”
Outside scientists said the report was exciting, in part because of some unusual factors in the patient’s case that may help answer fundamental questions about how these patients are able to clear the reservoir of HIV in their bodies.
In other successful cases of remission, patients had received their transplants but also suffered from graft vs. host disease, when the donor cells attack the recipient’s immune system. That did not happen in this case.
“Each of these cases is unique and different, and are there clues that help us focus on the next patient that comes along?” said Carl W. Dieffenbach, director of the Division of AIDS at the National Institute of Allergy and Infectious Diseases, who was not involved in the research.
Sharon Lewin, president-elect of the International AIDS Society, said in an email that the finding was exciting.
“A bone-marrow transplant is not a viable large-scale strategy for curing HIV, but it does present a proof of concept that HIV can be cured. It also further strengthens using gene therapy as a viable strategy for an HIV cure,” Lewin added.