During the congresses of theInternational Aids Society in Munich in July 2024 andHIV Drug Therapy in Glasgow in November 2024, the CISIH team (Human Immunodeficiency Information and Care Center) from the Sainte-Marguerite hospital in Marseilleled by Doctor Sylvie Brégigeon presented to her peers the exceptional case of a patient still in remission, 12 months after stopping her antiretroviral treatments.
Treatment for leukemia
Now aged around sixty, the patient was diagnosed with HIV in 1999. Immediately treated with antiretroviral drugs, it was only from 2010 that her treatment was truly effective, with a viral load that had become ” undetectable”, that is to say controlled by the treatment. In 2020, she developed acute myeloid leukemia.
Allogeneic bone marrow transplant
An allogeneic bone marrow transplant carried out at the Paoli-Calmettes Institute during the year allows her to treat her leukemia. “The team from the Paoli-Calmettes Institute managed to find a donor who was not only compatible but also had a particularity sought in this type of case: a deletion called Delta32 in the CCR5 gene, a co-receptor used by the virus of HIV as a gateway into the cells of people it has infectedes. In fact, the rare people in the world with this genetic mutation on both alleles of the CCR5 gene cannot be infected with HIV. explains Dr. Brégigeon in the hospital press release.
To date, only 7 cases of functional cure of HIV after allogeneic bone marrow transplantation, aimed at treating lymphoma or leukemia, have been reported in the world. For 6 of them, the donor carried the Delta 32 mutation on the CCR5 receptor.
-
No traces of the virus
Following her bone marrow transplant, the patient continued to take her antiretroviral treatment for almost 3 years after the transplant – until October 2023. More in-depth virological examinations were carried out during her monitoring, in collaboration with the Timone Virology Laboratory of Professor Philippe Colson: in particular ultrasensitive viral load tests, viral culture tests as well as a search for pro-viral DNA corresponding to the possible reservoir of viruses still present in his body. All of these tests came back negative. It was therefore decided to stop treatment. Still under surveillance, HIV was no longer detected and the rate de lymphocytes T CD4+ of the patient went from 250 to 1289/mm3 at the last check, normal values being between approximately 650 and 1500/mm3. Let us remember that theCD4+ T lymphocytes are a category of white blood cells targeted by HIV to destroy them and multiply at their expense.
Cases that cannot be generalized but bring hope
This allograft strategy is unfortunately not reproducible in all HIV-infected patients. It indeed involves very heavy conditioning with intensive chemotherapy, radiotherapy, long hospitalization in sterile rooms… only possible and justifiable in the context of the treatment of a malignant hematological disease such as lymphoma or leukemia. Nevertheless, these exceptional cases of remission allow an ever finer understanding of how HIV works and greatly contribute to opening up new research perspectives.
