Third Transplant Patient Cured of HIV Marks Important Firsts
February 16, 2022 — News this week that a third person has been ‘cured’ of HIV through a unique stem cell transplant has raised hope for a larger way to quell the HIV epidemic that has plagued the world for decades. But while this case certainly causes joy, the experts involved in the effort say we are still far from a universal cure.
Researcher Yvonne Bryson, MD, head of pediatric infectious diseases at UCLA, told attendees at an infectious disease conference on Tuesday that this case is special. The patient was a multi-racial woman living with HIV. The previous two patients were male: one white one Hispanic.
- The woman, in this case, received a stem cell and cord blood transplant to treat leukemia. The treatment resulted in remission not only of her cancer but also of her HIV.
- The researchers say the success of this case suggests that umbilical cord stem cell transplantation should be considered to achieve remission and treat HIV-infected people who also have cancer and other diseases.
Although the news was greeted with enthusiasm in the scientific community, this approach will not be publicly available since all transplants were done to treat cancer in three HIV-infected patients. Overall, Bryson estimates that this procedure could benefit about 50 people a year.
However, other experts say this approach could provide insight into other treatments. And Bryson says this opens up opportunities for more diverse populations.
“Bone marrow transplantation is not a viable large-scale HIV treatment strategy, but it represents proof that HIV can be cured,” says Sharon Levin, MD, president-elect of the International AIDS Society. “It also further strengthens the potential for gene therapy as a viable HIV treatment strategy.”
A woman needed a stem cell transplant after she was diagnosed with leukemia, a blood cancer. The stem cell transplant technique used was also new, says Bryson. The medical team used a combination of adult stem cells from a relative’s blood and cord blood from a cord blood bank, which had a rare mutation that makes the immune system resistant to HIV.
In the previous two cases of HIV cure after transplantation, both patients received stem cell transplantation with the same mutation but with bone marrow transplantation, which is a more complex procedure. And they didn’t use cord blood.
The combination of adult cells and cord blood cells proved to be the key to success. The researchers say the use of adult cells provides a bridge of sorts that helps until cord blood takes over. By the 100th day after the transplant, the woman actually had a new immune system, according to Bryson.
HIV remained undetectable in T cells and bone marrow. And 37 months after the transplant, the woman stopped taking antiretroviral therapy, usually prescribed to treat HIV infection.
“She is currently clinically healthy,” says Bryson. Her cancer is also in remission.
Case histories: three patients
The middle-aged woman demanded confidentiality, asking not to disclose her age or other details. But researchers have provided some information about her medical history and her path to recovery. She was diagnosed with HIV in 2013 and started antiretroviral therapy (ART). Four years after she was diagnosed with HIV, she developed high-risk acute myelogenous leukemia, a blood cancer. The transplant was done to cure it.
Her recovery was much less bumpy than the previous two patients, the researchers said. She left the hospital 17 days after the transplant. She did not have the serious complications of the first two, who developed a condition that occurs when the donor’s bone marrow or stem cells attack the recipient.
“This case also shows that it is the transplantation of HIV-resistant cells that has been the key to a cure here,” says Levin of the International AIDS Society. The first patient to have an HIV remission after a stem cell transplant, a white male, was in remission for 12 years and was declared cured but died of leukemia in September 2020. The other, a Hispanic, has been in remission for over 30 months.
HIV statistics, ethnic/racial burden
According to HIV.gov, about 1.2 million people in the United States are infected with HIV, although 13% of them do not know they are infected. In 2019 34,800 new infections have been diagnosed.
According to federal statistics, some ethnic and racial groups are more likely to be affected by HIV than others, given their proportion of the US population. For example, in 2019, African Americans made up 13% of the US population but 40% of those infected with HIV. Hispanics/Latinos made up 18.5% of the total population, but 25% of those diagnosed with HIV.
Inequality also affects women unevenly, with black women suffering disproportionately compared to women of other ethnic and racial groups. The annual rate of HIV infections among black women generally remained stable from 2015 to 2019, but according to federal statistics, the rate of new HIV infections among black women is 11 times higher than white women and four times higher than white women. Hispanics.
Expert point of view, reaction
Vincent Marconi, MD, professor of infectious diseases at Emory University School of Medicine, whose research focuses on differences in responses to HIV treatment, called the news “an exciting development for the treatment program. This is the first woman to have been cured in at least 14 months, and they used cord blood, which could allow for potentially less toxic regimens and fewer side effects.” While an approach designed to treat cancer won’t be widely available, he says “it provides insight into several related alternative treatment models using gene therapy.”
Meanwhile, Marconi and other researchers are also focusing on the concept of long-term HIV remission if a cure is not possible. Strategies being studied include gene editing and immune treatment. HIV remission is usually defined as the presence of an HIV viral load that is not detectable after stopping treatment.