Researchers revealed on Monday that a man infected with HIV may be the second person to beat the virus that causes AIDS, a development that takes the fight in finding a cure a giant leap forward.
According to the research, which was published Monday in the journal Nature, almost three years after receiving a stem-cell transplant from a donor who was genetically resistant to HIV, extensive testing shows that the man, whose identity was not revealed, has no detectable sign of the virus. Adding to the finding’s veracity, the man has been off of antiretroviral drugs — which keeps HIV in in check — for 18 months.
“This will inspire people that cure is not a dream,” said Dr. Annemarie Wensing, a virologist at the University Medical Center Utrecht in the Netherlands, according to The New York Times. “It’s reachable.”
“He’s doing well,” said Ravindra Gupta, HIV researcher at University College London who led the study, according to The Wall Street Journal.
If the man continues to be free of HIV, he would join one other man, Timothy Brown, who was cured almost 10 years ago via stem-cell transplant.
With both patients being cured through the same treatment, the development will encourage concentrated research. “Having another proof of concept with the same approach is important,” Dr. Gupta told WSJ.
Nearly 37 million people worldwide have been infected with HIV, and scientists are struggling to find a cure for the disease — a virus notorious for hiding in the body and evading attempts to flush it out. More than 21 million take drugs that keep HIV alive but reduces the spread. According to WSJ, an estimated 1.8 million people were infected in 2017.
“When you have a single case report in medicine you never know if this is just an unusual set of circumstances,” said Sharon Lewin, director of the Peter Doherty Institute for Infection and Immunity at the University of Melbourne and Royal Melbourne Hospital, and co-chair of the International AIDS Society’s Towards an HIV Cure initiative. “The fact that it has now been repeated is really very exciting. It does demonstrate that a cure is possible.”
According to researchers, the approach used on the two men could not be universally applied to people with HIV. The method used is said to be risky and costly, with both men having diseases that warranted stem-cell transplant: Mr. Brown had leukemia and needed a transplant, and the “London patient” had Hodgkin lymphoma, WSJ said.
“It’s not a practical solution” for people who don’t have diseases that require a stem-cell transplant, said Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, the National Institutes of Health arm that leads HIV research, according to WSJ. But he said, “The fact that you have a second patient says yes, it can be done.”
The London man, and Mr. Brown before him, both received stem-cell transplants from donors who had two copies of a key mutation to a gene called CCR5. The vast majority of HIV strains use normal copies of this gene to gain entry to a patient’s immune-system cells, WSJ said.
According to The Times, most experts who know the details agree that the new case seems like a legitimate cure, but some are uncertain of its relevance for AIDS treatment overall.
“I’m not sure what this tells us,” said Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases. “It was done with Timothy Ray Brown, and now here’s another case — ok, so now what? Now where do we go with it?”
One possibility, said Dr. Deeks and others, is to develop gene-therapy approaches to knock out CCR5 on immune cells or their predecessor stem cells. Resistant to H.I.V. infection, these modified cells should eventually clear the body of the virus, according to The Times. (CCR5 is the protein that He Jiankui, a scientist in China, claimed to have modified with gene editing in at least two children, in an attempt to make them resistant to H.I.V. — an experiment that set off international condemnation.)