A cure for HIV is extremely rare today, despite the considerable progress that research has made in this field. So far, only three cases have been documented worldwide, the most recent of which was in a woman in the USA. Importantly, the people who recovered from HIV had received a transplant from compatible donors, but they had a mutation in the CCR5 gene that confers resistance to HIV. The case was presented at the CROI Congress (Conference on Retroviruses and Opportunistic Infections).
The first case is that of Timothy Ray Brown, who lived for 12 years without antiretroviral drugs after a bone marrow transplant to treat leukaemia. The second case is that of an HIV-positive man with non-Hodgkin’s lymphoma. He was treated with chemotherapy and then underwent a bone marrow transplant to replenish his blood with red and white blood cells that had previously been “destroyed” by the chemotherapy. When he recovered from the tumour, HIV was no longer detectable in his blood. The cancer treatment and the transplant had the side effect of eliminating the virus.
The third case, which is the most unusual and different from the other two, involves an American woman. Unlike the two men who were cured of HIV by a bone marrow transplant, the woman had no autoimmune reaction to the transplanted cells because she had received a transplant of stem cells from the umbilical cord of a partially compatible donor in combination with a blood transfusion from a relative.
Thirty-seven months after the stem cell transplant, the woman discontinued antiretroviral therapy as she was completely cured of the virus. A state of seronegativity that has lasted for over 14 months.
This is a great achievement thanks to stem cells, cells that can be used to treat various diseases thanks to their ability to differentiate.