The Oslo patient is the seventh man in the world likely cured of HIV: "Offers hope"
Researchers at Oslo University Hospital have closely examined the man's blood, bone marrow, and intestines without finding any trace of active HIV virus.
More than 30 researchers at Oslo University Hospital have been involved in the work on the Oslo patient. Some of the most central figures are gathered in this photo. From left: Malin Holm Meyer-Myklestad, Mari Kaarbø, Marius Trøseid, Hanne Hestdal Gullaksen, and Anders Myhre.(Photo: Malu Katalina Marie Lian Hestdalen / Oslo University Hospital)
The Oslo patient was diagnosed with HIV in 2006, when he was 44 years old.
About 15 years later, in 2020, he underwent a bone marrow transplant to treat a blood disorder.
Last year, his Norwegian doctors announced to the world that the man, now in his 60s, was most likely also cured of HIV.
"I've never been part of anything bigger in my medical career," reported Professor Marius Trøseid from the large HIV conference CROI in San Francisco, where the results about the Oslo patient were presented.
The man has been monitored for another year. Doctors have conducted even more tests. The work has been peer-reviewed by other researchers. And the virus has still not returned.
"It's even more likely that what we’ve reported is a genuine cure," Trøseid tells Science Norway.
As a growing number of people are now being cured of HIV, it raises hope that it may truly be possible to develop a cure for the virus itself, according to the professor.
"There's a clear rise in enthusiasm for this within the field," he says.
Today, the condition is kept in check with a daily pill. But if you stop taking that pill, the virus flares up again.
It has been nearly 20 years since the world discovered that it was indeed possible to get rid of the virus.
The Berlin patient, who received a bone marrow transplant in 2007, is considered the first in the world to be cured of HIV. The Oslo patient is now the seventh case believed to have been cured in this way.
But many more people with HIV have undergone bone marrow transplants.
"To determine whether someone is cured, you have to be willing to stop treatment," explains Trøseid. "We are among the few who have done this, with the Oslo patient."
There are also three patients who received bone marrow transplants but were not cured of HIV.
HIV-protective mutation is not decisive
Previously, researchers believed the key difference between being cured or not was a genetic mutation.
Annonse
The CCR5delta32 mutation protects against most variants of HIV. It is most commonly found among people in Northern Europe.
The Oslo patient received a bone marrow transplant from his twin brother, who happened to carry this mutation.
But two patients have been cured without this mutation, according to Trøseid.
"The mutation likely provides an extra layer of protection," he believes.
But Trøseid and his colleagues believe there is also something else that helps eliminate the virus.
After bone marrow transplants, patients may experience that the transplanted immune cells attack the body's organs. This is called graft-versus-host disease. The reaction can be mild and barely noticeable, or severe and require treatment.
The Norwegian researchers believe that this response is the key to removing the HIV virus.
"Our hypothesis is that when the new immune system replaces the old one, it eliminates the infected cells from the original system," says Trøseid. "If the new immune system takes over quickly and completely removes the old one, we believe there's a greater chance of being cured."
The Oslo patient is now one of the best-documented cases in the world of long-term HIV remission following a stem cell transplant, according to chief physician and professor Marius Trøseid and the team behind the recently published study.(Photo: Øystein H. Horgmo / Oslo University Hospital)
A new immune system has taken over
To confirm that the Oslo patient is truly free of HIV, Norwegian researchers have carried out extensive testing of his blood, bone marrow, and intestines.
More than 65 million T-cells have been analysed. No inactive virus was detected. And none of the T-cells recognised the HIV virus.
The patient is still being monitored with tests every three months.
At Ullevål University Hospital, researchers have long studied the role of the gut in HIV infection, as the intestines are the body’s main reservoir for the virus.
"Thanks to this research environment, we were able to examine the patient more thoroughly than ever before," explains Trøseid.
While traces of old HIV DNA were detected, researchers found no intact virus in the intestines.
"All our findings indicate that a new immune system has taken over. The old one, which was infected with HIV, has been replaced," says Trøseid.
May point the way forwards
The researchers hope their work will help define which tests are needed to determine whether a patient can be considered cured or not.
"And that it may encourage more people to consider stopping HIV treatment in transplant patients," says Trøseid.
The more people who are cured, the more researchers can learn about the mechanisms behind a cure.
The question is whether it can help people beyond those who have undergone bone marrow transplants.
"It's not certain that what we find in bone marrow transplant patients will carry over into studies of a cure for others," says Trøseid.
But it's possible they may find something that proves useful.
"We hope they can help guide us towards where we should look for ways to target and reduce the amount of virus in the body," says Trøseid.
Mari Kaarbø leads the Virology Research Group at Oslo University Hospital's Department of Microbiology, which has been crucial in analysing the virus reservoirs in the Oslo patient.(Photo: Grete Hansen)
Has brought an HIV cure into focus
Bone marrow transplantation is only a viable HIV cure for patients who also suffer from another serious condition, usually a form of blood cancer requiring such treatment.
Even so, these cured patients have inspired an entire field, according to Trøseid.
At last year's conference in San Francisco, the first day was, for the first time, entirely dedicated to finding a cure for HIV.
Oslo University Hospital is now part of a European collaboration aimed at finding a cure for HIV, the professor notes.
It has been 30 years since Trøseid first met someone with HIV. That was also around the time the first HIV medications became available – treatments that turned HIV into a chronic condition and, as a result, somewhat reduced the priority of research on the virus.
"I have followed this field closely for many years, and the fact that we are now starting to talk about the possibility of a functional cure is very meaningful," he says.
Carried out very thorough work
"This is an interesting article showing that it's possible to remove HIV reservoirs and thereby cure HIV," says Jan Kristian Damås.
Damås is a chief physician at St. Olavs Hospital and a professor at NTNU, where he has conducted research on HIV. He is not involved in the work on the Oslo patient.
He notes that earlier research has shown that bone marrow transplants involving the CCR5delta32 mutation can cure HIV.
"But this new article takes a very thorough approach, showing no trace of HIV in the blood, intestines, or bone marrow after such a transplant," he says.
However, he emphasises that bone marrow transplantation is a treatment with many complications and is reserved for serious cancers.
"It will not become a standard treatment for HIV," he says. "Current HIV treatments, including pills or injections every other month, are highly effective and have few side effects. Still, this work provides momentum for further research into new treatment methods that may one day cure HIV."
