Europe 1 with AFP 5:34 p.m., February 20, 2023

A bone marrow transplant resulted in a new official case of HIV cure in Dusseldorf, Germany.

Only two similar healing cases have been described so far in scientific publications.

All the patients concerned had a very particular situation in common.

This is a new official case of recovery from 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

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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.

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 any viral particles, nor any activatable viral reservoir, nor immune responses against the virus in the organism of this person despite the cessation of treatment for 4 years.

All patients had blood cancer

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.

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"During a bone marrow transplant, the patient's immune cells are completely replaced by those of the donor, which makes it possible to make the vast majority of infected cells disappear", explains, in a press release, the virologist Asier Sáez-Cirión. , one of the authors of the study.

An operation that remains heavy and risky

"This is an exceptional situation when all these factors coincide for this transplant to be a double success in curing leukemia and HIV," said the researcher.

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.