An American has become the fourth person in the world, and the first woman, to have been cured of HIV after undergoing a transplant of umbilical cord blood stem cells, which were combined with stem cells from a close relative to increase the chances of success.
The so-called 'New York patient' also suffered from a type of leukemia, which made a bone marrow transplant necessary, and has been free of the virus since 2017, a period that, due to other similar cases, is considered reasonable to consider that it may be cured.
This case was announced a year ago at a medical congress, but until now the results had not been published in any scientific journal, which was done this Thursday by the magazine Cell, whose team is headed by the University of California (UCLA) and the Johns Hopkins.
Today four people consider themselves cured of HIV, patients from Berlin, London, Düsseldorf and now New York. All suffered from leukemia that required a bone marrow transplant, a risky intervention that is only indicated in hematological cancers.
The case of the New York patient, a middle-aged woman who identifies as "racially mixed", has several peculiarities compared to the others, the first to undergo a transplant of HIV-resistant stem cells from cord blood umbilical cord and not from a matched adult donor.
The team believes that the treatment has given "satisfactory long-term results," the study indicates, and that the use of umbilical cord blood stem cells increases the chance of curing HIV in people of all racial origins.
The use of umbilical cord blood cells "expands the opportunities for people of diverse ancestry living with HIV who require transplantation for other conditions to achieve a cure."
The patients in Berlin, London and Düsseldorf received stem cell transplants from matched adults who carried two copies of the CCR5-delta32 mutation, a natural mutation that confers resistance to HIV by preventing the virus from entering and infecting cells.
Only about 1% of white people are homozygous for the CCR5-delta32 mutation and it is even rarer in other populations, limiting the possibility of transplantation in racialized patients, since stem cell transplants often require a high donor match. and the receiver.
These conditions made it almost impossible to find an adult donor with the aforementioned mutation and compatible with the patient, so in 2017 the team transplanted stem cells carrying CCR5-delta32/32 from stored umbilical cord blood to try to simultaneously cure the cancer and HIV.
In addition, these cells were infused with stem cells from one of the patient's relatives to increase the chances of success of the procedure.
"With cord blood, you don't have as many cells and they take a little longer to populate the body after infusion," but using a mixture of stem cells from a relative and cord blood "gives a boost to the cells of umbilical cord blood," Bryson said.
The transplant managed to put both HIV and leukemia into remission, which has lasted for more than four years. Thirty-seven months after the transplant, the patient was able to stop taking the anti-HIV medication. The doctors who follow her say that she has not contracted HIV for more than 30 months since she stopped antiviral treatment (at the time the study was written, only 18 months had passed).
"Stem cell transplants with CCR5-delta32/32 cells offer a two-for-one cure for people living with HIV and blood cancers," said Deborah Persaud of Johns Hopkins University and co-leader of the study, quoted by Cell.
However, due to the invasiveness of the procedure, stem cell transplants (both with and without the mutation) are only being considered for people who need a transplant for other reasons, and not to cure HIV alone, a disease for which that there is medication
The study also highlights the importance of having CCR5-delta32/32 cells in stem cell transplants for patients with HIV, since all the cures, up to now, "have been with this population of mutated cells, and the studies in which New stem cells that have been transplanted without this mutation have not been able to cure HIV," Persaud said.