A third person has just been cured of HIV, after a bone marrow transplant. The “Dusseldorf patient” no longer has any trace of the virus in his body, according to work published Monday in Nature Medicine.
Only two similar healing cases have been described so far in scientific publications: the patient from Berlin in 2009 and the patient from London in 2019. Two other cases of healings were detailed last year at scientific conferences, but have not yet given rise to publications in due form.
A stem cell transplant
This third patient, a man followed in Düsseldorf, received a stem cell transplant to treat leukemia, then was able to interrupt his antiretroviral treatment against HIV, described the international consortium IciStem, of which the Institut Pasteur is a partner, in the ‘study. In their analyses, the researchers did not find viral particles, nor an activatable viral reservoir, nor immune responses against the virus in the organism of this person despite the cessation of treatment for four years.
The cured patients all have a very particular situation in common. They were suffering from blood cancers and benefited from a stem cell transplant which deeply renewed their immune system. Their donor had a rare mutation in a gene called CCR5, a genetic mutation known to prevent HIV from entering cells.
Very few compatible donors
“During a bone marrow transplant, the patient’s immune cells are completely replaced by those of the donor, which makes it possible to eliminate the vast majority of infected cells, explains, in a press release, the virologist Asier Sáez-Cirión, one of the authors of the study. It is an exceptional situation when all these factors coincide for this transplant to be a double success in curing leukemia and HIV. »
Since less than 1% of the general population carries this HIV protective mutation, it is indeed very rare for a compatible marrow donor to have this mutation. In 2018, the medical team no longer detected the presence of the virus and planned with the patient a supervised discontinuation of antiretroviral treatment against HIV.
But, if these cases of remission bring hope to researchers of one day overcoming HIV, a bone marrow transplant remains a very heavy and risky operation: it is not adaptable to most carriers of the virus.