The IMPAACT P1107 protocol team presented the first known case of a woman with HIV remission following a stem cell transplant for treatment of acute myelogenous leukemia (AML) at CROI 2022 on 15 February. The transplant consisted of cord blood stem cells with the CCR5Δ32 genetic mutation and haploidentical peripheral blood stem cells from a relative. Since having the stem cell transplant, the participant has been in remission for AML.
The participant’s HIV infection was well-controlled on antiretroviral therapy (ART) prior to the stem cell transplant and through 37 months post-transplant, at which time she stopped ART. With the exception of transient detection of trace levels of HIV-1 DNA in blood cells 14 weeks after stopping ART, no HIV has been detected for 14 months. Based on these results, the participant has been deemed in HIV remission.
HIV remission resulting from a stem cell transplant had been previously observed in two cases. The first, known as the “Berlin patient” (a Caucasian male), experienced HIV remission for 12 years and was deemed cured of HIV. He died of leukemia in September 2020. The “London patient” (a Latino male) has been in HIV remission for more than 30 months. This third case, reported from IMPAACT P1107 in a woman of mixed race, suggests that CCR5Δ32 cord stem cell transplantation should be considered to achieve HIV remission for people living with HIV who require such a transplant for another illness.
About IMPAACT P1107
IMPAACT P1107 is an observational study of persons living with HIV in the U.S. who undergo transplantation with CCR5Δ32 cord blood stem cells for treatment of cancer or other illness. The study began in 2015 and has been conducted by the International Maternal Pediatric Adolescent AIDS Clinical Trials (IMPAACT) Network, in collaboration with the Center for International Blood and Marrow Transplant Research (CIBMTR), StemCyte, and the AIDS Clinical Trials Group (ACTG).
The CCR5Δ32 genetic mutation results in T cells that are missing CCR5 co-receptors. HIV uses these co-receptors to infect T cells. T cells are part of the immune system. Scientists theorize that chemotherapy given to people with cancer or other illness, followed by a transplant with stem cells that carry the CCR5Δ32 mutation, can change the immune system to make it resistant to HIV.