A woman has been declared HIV-free after receiving a stem cell transplant.
The woman known as the “New York patient” has been HIV-free and off her medication for around 30 months.
The patient received stem cells taken from umbilical cord blood, which contained HIV-resistant genes, and stem cells from a relative, to bridge the gap until the HIV-resistant cells started to come in.
Breakthrough in HIV Research
Only a few people have been cured of HIV at this point in time. And whilst HIV has not returned for those people, it is not being referred to as a cure just yet, due to the small sample size of people who have gone into remission.
“We’re calling this a possible cure rather than a definitive cure — basically waiting on a longer period of follow up,” said Dr Yvonne Bryson, director of the Los Angeles-Brazil AIDS Consortium at the University of California, during a news conference.
The patient first received the stem cell transplant in August 2017. She stopped taking antiretroviral therapy (ART) just over three years later and has been off medication for 2.5 years.
“Right now, she’s still doing very well, enjoying her life,” Dr. Jingmei Hsu, director of the Cellular Therapy Laboratory at NYU Langone Health said at the news conference.
All the cured patients had cancer
All the cured HIV patients had been treated for cancer. Previous patients had been given stem cell transplants taken from bone marrow.
These transplants used bone marrow stem cells from adult donors who carried two copies of a rare genetic mutation known as CCR5 delta 32. This mutation changes the way that HIV typically uses to enter white blood cells and thus blocks the virus from entering.
After transplantation, the donor stem cells take over the patient’s immune system, with the old cells that are vulnerable to HIV being replaced with new, HIV-resistant ones. To clear the way for the new immune cells, doctors wipe out the original immune cell population using chemotherapy or radiation therapy- for this reason, the treatment is not recommended for HIV-positive patients unless they are fighting cancer.
Umbilical cord blood is seen as a better alternative to bone marrow due to it being easier to access and less invasive.