A 60-year-old man from Berlin is the seventh person globally to achieve long-term HIV remission following a stem cell transplant for leukemia, according to research published Monday in *Nature*.the case is particularly significant as it demonstrates that HIV remission may be attainable even with donors who don’t possess the most common genetic mutation conferring resistance to the virus. This advancement offers a promising step forward in the decades-long search for a curative pathway for the estimated 39 million people living with HIV worldwide [[1]].
A 60-year-old man from Berlin, Germany, has become the seventh person worldwide to achieve long-term HIV remission following a stem cell transplant to treat leukemia. The case was detailed in a study published in Nature on Monday, February 26.
The patient was originally diagnosed with HIV in 2009 and later developed acute myeloid leukemia in 2015. As part of his cancer treatment, he underwent a stem cell transplant from a compatible donor and subsequently entered remission from the HIV infection.
This case differs from previous reports of HIV remission after stem cell transplantation because the donor was a “heterozygote” for a genetic variant called CCR5 Δ32, which blocks the main entry point for HIV into cells. This means the donor had only one copy of this mutation, rather than the usual two. Despite this, the patient was able to stop antiretroviral therapy three years after the transplant and has remained free of HIV. This finding is significant because it suggests that achieving remission may be possible with a wider range of donors.
Researchers say the new case demonstrates that two copies of the CCR5 Δ32 mutation aren’t necessary to achieve HIV remission. Having just one copy expands the potential pool of compatible donors and increases the chances of a cure. The development offers renewed hope in the ongoing search for an HIV cure.
The recent findings also suggest that other factors play a crucial role in HIV remission, including reducing or eliminating so-called “viral reservoirs”—cells where the virus can hide within the body. Understanding these reservoirs is a key focus of current HIV research.
Before the transplant, the patient had detectable HIV in his system. After the procedure, even with highly sensitive tests, no viral particles capable of replicating were found in either his blood or tissues. Immune responses specific to HIV also diminished or disappeared, indicating the virus was no longer actively present in his body, according to the study.
The study authors believe this case could pave the way for broader HIV cure strategies that don’t solely rely on transplantation. Further research is needed to explore these possibilities.
Who are the other patients who have achieved remission?
The first reported case of an HIV-cured patient was Timothy Ray Brown, known as the “Berlin patient.” He was diagnosed with HIV in 1995 in Germany and received a leukemia diagnosis in 2006.
The second man cured was Adam Castillejo, known as the “London patient.” He had Hodgkin’s lymphoma and underwent a bone marrow transplant in May 2016 using material from a donor with the mutation in the CCR5 gene.
In 2022, two additional cases were announced: in February, a woman received a treatment using umbilical cord blood from a donor with the CCR5 mutation and partially matched stem cells from a first-degree relative.
Shortly after, in July, the fourth case of HIV cure was reported. The 66-year-old man, who wished to remain anonymous, was nicknamed the “City of Hope patient.”
In 2023, scientists at the University Hospital Düsseldorf in Germany announced the fifth patient cured of HIV after a bone marrow transplant. Known as the “Düsseldorf patient,” he also had leukemia and received stem cells from a donor with genetics resistant to the virus, similar to previous cases.
Also in 2023, a man in Switzerland, nicknamed the “Geneva patient,” achieved HIV remission after undergoing a bone marrow transplant. His case was unique in that the bone marrow received did not have the CCR5 Δ32 mutation.
