Breakthrough in HIV cure: Seventh person worldwide appears cured

A German resident may be part of a groundbreaking medical milestone after apparently being cured of HIV, a feat accomplished by only six people worldwide in over four decades since the AIDS epidemic began.

The German man, who preferred to remain anonymous, was treated for acute myeloid leukemia (AML) with a stem cell transplant in October 2015. He stopped taking his antiretroviral drugs, which are taken as treatment to keep HIV at a low level, in September 2018.

The man has remained in a state of "viral remission," meaning that repeated tests have not detected any trace of HIV in his body.

In a statement about his condition, the man said, "a healthy person has many wishes, a sick person only one."

The case is expected to be presented soon at the International AIDS Conference in Munich.

This man is the seventh person in the world who appears to have been cured of the virus. However, experts have tempered the excitement with a warning that the treatment undergone by the carriers will be available to only a few—all the patients contracted the virus and later developed blood cancer that required a stem cell transplant to treat the malignancy.

The bone marrow donors had immune cells with a rare resistance to the HIV virus, which likely helped eliminate all copies of the virus in the patients' bodies.

The difficulty of curing HIV

The HIV virus is difficult to cure, partly because it creates many mutations that make it challenging to develop an effective vaccine. Additionally, some of the cells it infects in the body are "dormant" immune cells that do not destroy the virus. Carriers are required to take antiretroviral drugs that inhibit the virus's replication but do not completely eliminate it.

In five out of the seven cases of a clear or possible HIV cure, doctors found bone marrow donors with rare and natural defects in both copies of a gene that creates a certain protein called CCR5 on the surface of immune cells. Most strains of HIV attach to this protein to infect cells. Without functional CCR5 proteins, immune cells are resistant to HIV.

The donor to the German man had only one copy of the CCR5 gene, meaning his immune cells likely have about half the normal amount of this protein. Additionally, he had only one copy of the gene itself. Together, these two genetic factors may have increased his chances of being cured.

While having two copies of the defective CCR5 gene is rare, occurring in about 1% of people with northern European ancestry, one copy occurs in about 16% of such people.

Who are the six others cured of HIV?

The other six patients who are believed to have been cured of the virus begin with Timothy Ray Brown, known as the "Berlin patient," who was the first man reported to be cured of HIV. 

Brown, an American living in Germany, was treated for AML cancer. He was cured of HIV but died from recurrent leukemia in 2020.

Adam Castillejo, known as the "London patient," is a Venezuelan-born man living in England. He received a stem cell transplant for blood cancer. In 2016, he stopped taking HIV medication and was also considered cured.

Marc Franke, known as the "Düsseldorf patient," was treated with a stem cell transplant for AML blood cancer in 2013. Franke, 55, stopped taking antiretroviral drugs for HIV in November 2018 and is considered healthy.

Paul Edmonds, known as the "City of Hope patient." Edmonds is the oldest of the recovered patients, at 63. He received a bone marrow transplant in 2019 and has not taken HIV medication since March 2021.

Next year, five years after stopping HIV treatment, he will be considered fully cured. He expressed excitement about the new case of a person who is apparently cured, saying, "My vision is clear: a world where HIV is no longer a sentence but a footnote in history."

"The New York patient" is another woman who was diagnosed with leukemia in 2017 and received a stem cell transplant from umbilical cord blood.

The "Geneva patient" is a man in his 50s who was diagnosed with a rare blood cancer in 2018 and has not received HIV treatment since November 2021 after also receiving a bone marrow transplant. In this case, too, doctors are cautious and waiting until the fifth year without HIV treatment to declare him cured.