The second patient in Berlin, the seventh case of HIV cure in the world

BarcelonaThere are now seven people in the world who have been cured of HIV. One of them is a man known as the second patient in Berlin, who received a positive diagnosis for the virus in 2009 and another for leukemia in 2015. To treat the cancer, the patient received a stem cell transplant from a donor, a therapy that had previously been successful in a few HIV-positive individuals, rendering the presence of HIV undetectable in their blood. However, in all previous cases of cure, the donors were homozygous, meaning they had two identical copies of a gene whose mutation is considered protective against the virus. This time, however, researchers from the Berlin Institute of Health and the University of Berlin have managed to cure him using cells from a donor who only had one of the two copies with the mutation, suggesting that the pool of donors with the potential to eliminate HIV could be larger than expected.

The journal Nature The results of the study describing the cure of this 60-year-old German man, who six years after the transplant still shows no detectable presence of the virus in his blood, are published this Monday. The patients who inaugurated the short list of those cured of HIV were Timothy Ray Brown, known as the Berlin patient, in 2011, and a year later Adam Castillejo, the London patientBoth received a bone marrow transplant from a donor with a rare mutation, called CCR5 Delta32, which has not worked in other cases. Most previous patients were cured after receiving transplants from donors homozygous for a mutation in the CCR5 gene that is considered protective against the virus. Now, the study authors describe the seventh case of remission in a 60-year-old man with leukemia in whom the donor had only one of the two copies with the mutation, suggesting that the pool of donors with the potential to clear HIV could be larger. Alternative strategies

For Javier Martínez-Picado, a member of the IciStem consortium, co-directed by the IrsiCaixa AIDS Research Institute in Barcelona and the University Medical Center Utrecht (Netherlands), and responsible for several HIV cure cases, this study is "a very detailed and high-quality piece of work" that confirms previously published cases of hematopoietic stem cell transplantation from a donor. And although this type of medical intervention is reserved "exclusively" for people with a serious hematological disease, "alternative strategies are being explored," he told Science Media Center (SMC).