Science and Technology Daily (intern reporter Zhang Jiaxin) According to foreign media news, researchers reported on July 27 that a 66-year-old leukemia patient had long-term remission of AIDS after receiving a stem cell transplant, or had achieved a "cure".

This is the fourth AIDS patient in the world to be declared "cured" and the oldest patient at present.

　　The patient is being treated at City of Hope Medical Center in Duarte, California.

Because he did not want to be named, he was called the "City of Hope" patient.

Currently, he has been off antiretroviral therapy (ART) for 17 months and has yet to show any signs of HIV replication in his body.

　　In addition to being the oldest, this patient was also the longest infected with HIV.

He was diagnosed with AIDS in 1988.

For 30 years, he has been on ART to manage his condition, but has failed to effectively treat HIV.

　　In 2018, the patient developed acute myeloid leukemia (AML), a cancer of the blood and bone marrow.

He underwent chemotherapy to relieve the leukemia.

Due to his older age, he underwent lower-intensity chemotherapy in preparation for a stem cell transplant.

　　Doctors then performed a hematopoietic stem cell transplant using cells from a donor with a rare genetic mutation.

The mutation, called homozygous CCR5 delta 32, makes its carriers resistant to HIV by altering the virus's usual entry point into the body's white blood cells.

It is an improved treatment for hematopoietic stem cell transplantation, better tolerated by older adults with blood cancers and reduces the likelihood of transplant-related complications.

This method originally cured the "Berlin patient" Timothy Ray Brown in 2007.

　　The City of Hope patient stopped receiving ART in March 2021.

His AIDS and leukemia were in remission for more than a year, the team said.

　　The researchers presented the data to the 24th International AIDS Congress on July 29.

They say the case opens up the possibility of a cure for older patients with AIDS and blood cancer, especially if the donor is not a family member.

　　Sharon Lewin, president-elect of the International AIDS Society, said the case provided "continued hope and encouragement" for people living with HIV and the wider scientific community, although it was unlikely to be the case for most people living with HIV due to the risks of surgery user's choice.

　　The researchers believe the process works because the donor's stem cells have a specific, rare genetic mutation that means they lack the receptors that HIV uses to infect cells.

　　On July 27, researchers in Spain also released details of a 59-year-old woman, one of a handful of people known as "post-treatment controllers."

Even though she stopped receiving ART, she maintained an undetectable viral load for 15 years, which could provide clues to a potential cure, Levine said.