A sixth person appears to have been cured of HIV after receiving a stem cell transplant. However, the so-called “Geneva Patient” appears to be slightly different from other cases. He didn’t receive stem cells from someone with a known genetic mutation that confers HIV immunity.
A tiny number of people have a natural, genetic immunity to HIV.
If someone with HIV needs a stem cell transplant, and they receive the cells from someone with this immunity, they can be functionally cured of HIV. Their immune system is basically rebooted from scratch with the genetic modification included.
This has been observed five times previously. The reason why it’s not rolled out to help more people is simple. Stem cell transplants are risky procedures that require patients to have their entire immune system temporarily eradicated.
Those who undergo them may have to remain on drugs for the rest of their lives to prevent tissue rejection. It’s also hugely expensive. For this reason, it’s only usually people with cancers such as leukemia or sarcoma that undergo the procedure.
Researchers remain interested in the procedure in case it helps point toward a similar, more practical cure for HIV.
What makes this case different is the “Geneva Patient” did not receive a transplant from someone with the “CCR5” gene mutation. That’s the genetic blip that prevents HIV from entering cells.
The patient has now been off antiretroviral treatment for 20 months. He shows no signs of HIV rebounding within his body.
“Wonderful and magical”
The Switzerland-based man is in his early 50s and was diagnosed with HIV in 1990. In a press statement, he said, “What has happened to me is wonderful and magical. We can now focus on the future.”
The full information about the case will be revealed next week at the International AIDS Society Conference on HIV Science (IAS 2023) in Brisbane, Australia. However, ahead of that, Dr Asier Sáez‐Cirión of Institut Pasteur in Paris, outlined what had happened.
“All the markers of HIV infection very quickly decreased until they became undetectable by classic analysis within a few months. To date, 20 months after the treatment interruption, this person has not experienced viral rebound.”
Sáez‐Cirión continued, “All the immunological markers we have analyzed have been unable to detect HIV products, whether it’s the presence of provirus or low-level viral replication or viral RNA.”
The scientists could not rule out some tiny amount of HIV might be hiding in a latent reservoir within the man’s body. However, to date, they can find no trace of it.
It’s unclear yet what ramifications this finding could have. For now, the researchers want to try and determine why and how HIV disappeared within this man’s body. They’re wondering whether other medications he took, including the drugs to prevent rejection, may have shrunk the HIV viral load to a point where it disappeared. That will be among the focus of further investigations.
“This individual will need to be watched closely over the next months to years,” said International AIDS Society Co-Chair Professor Sharon Lewin of the University of Melbourne.