Remedy Deemed Too Risky for Healthy Patients After First Woman Cured of HIV

While a risky stem cell therapy has successfully cured the first woman of the human immunodeficiency virus (HIV), the procedure is deemed too dangerous to use on the average patient.

The therapy—known as a cord blood stem cell transplant—was given to an American woman from a donor who was naturally immune to HIV, according to a press release issued Tuesday from the National Institute of Allergy and Infectious Diseases (NIAID). She became the third person overall and first woman to be declared cured of HIV after the virus was not detected in her system within 14 months.

The case is also reportedly the first involving the use of umbilical cord blood, a newer approach could provide further breakthroughs.

However, despite the woman appearing to have been cured, researchers have reiterated that the therapy is still considered extremely risky and has only been tested on patients suffering from end-stage cancers, such as the woman—who had been diagnosed with acute myeloid leukemia. Experts told NBC News that it would even be considered "unethical" to attempt the transplant in an otherwise healthy patient due to its danger.

The risk comes, scientists stated, because of the nature of the transplanted bone marrow, which attacks a patient's cancerous immune system in an effort to replace it with one containing the HIV-immune cells of the donor. This, in theory, means that the patient's immune system is being completely replaced by another person's, which both treats the cancer and cures them of HIV.

Stem Cells
An experimental stem cell treatment has successfully cured a woman of HIV. However, the procedure is considered extremely risky and potentially dangerous, and as a result it is only being offered to HIV patients with end-stage cancer. Here, stem cells from human bone marrow can be seen under a microscope. iStock/Getty

"By killing off the cancerous immune cells via chemotherapy and then transplanting stem cells with the CCR5 genetic mutation, scientists theorize that people with HIV then develop an HIV-resistant immune system," NIAID said.

However, the complex procedure can often result in the death of the patient, scientists told NBC News, and as a result the treatment is not offered for those who do not already have a potentially fatal illness.

"[The stem cell treatment is] still not a feasible strategy for all but a handful of the millions of people living with HIV," Dr. Deborah Persaud, a pediatric infectious disease specialist at Johns Hopkins University and one of the chairs of the case study, stated. However, Persaud added that, despite this, her team was still "very excited" about the potential future of the treatment.

Additionally, Sharon Lewin, the president-elect of the International AIDS Society, expressed hope that the three combined cases could eventually be used to develop a stem cell therapy that is safe for the masses.

"Taken together, these three cases of a cure post stem cell transplant all help in teasing out the various components of the transplant that were absolutely key to a cure," Lewin said in a statement.

HIV and its associated illness, acquired immunodeficiency syndrome (AIDS), are most often treated using a combination of drugs and experimental tests, as in the three people who have been cured therapeutically. However, there have been extremely rare cases of an HIV-positive person being "naturally" cured of the virus.

In November 2021, a woman in Argentina became the second documented HIV patient whose own immune system cured her of the disease, with no outside intervention.

"This is really the miracle of the human immune system that did it," Dr. Xu Yu, one of the leaders of the Argentine case study, said at the time.

Newsweek has contacted the CDC's National Center for HIV, Hepatitis, STD and TB Prevention for comment.