A German man has likely been cured of HIV, a medical milestone that only six other people have achieved more than 40 years after the AIDS epidemic began.
The German man, who wishes to remain anonymous, was treated for acute myeloid leukemia (AML) with a stem cell transplant in October 2015. He stopped taking antiretroviral drugs in September 2018 and is in viral remission without rebound. Multiple ultrasensitive tests have not detected any viable HIV in his body.
“A healthy person has many wishes, but a sick person has only one,” the man said in a statement about his recovery.
The case, which investigators say offers important lessons for HIV treatment research, will be presented on the 25th by Dr. Christian Gaebler, a physician-scientist at Charité University Medicine Berlin. International AIDS Conference In Munich.
“The longer HIV remission lasts without HIV treatment, the more confident we can be that we’re looking at a case where we’ve truly eradicated all active HIV,” Gaebler said.
As with previous cases of potential HIV cures, experts are trying to temper public excitement with a word of caution: The treatment that appears to have halted the virus in the seven patients is available only to a select few, all of whom were infected with HIV and later developed blood cancers that required stem cell transplants to treat their malignancies.
The transplanted cells, most often from donors chosen because they contain immune cells that HIV targets, boast a rare natural resistance to the virus and appear to have helped eradicate all viable, and therefore functional, copies of the virus from the body.
Stem cell transplants are highly toxic and potentially fatal, so it is unethical to perform stem cell transplants on people with HIV unless they are treating another disease, such as a blood cancer.
Treating HIV is extremely difficult This is because some of the cells that are infected are long-lived immune cells that are dormant or becoming dormant. Standard antiretroviral treatments for HIV only affect immune cells that are actively making new copies of the virus, as typically found in infected cells. As a result, HIV in dormant cells goes undetected. Collectively, these cells are known as viral reservoirs.
At any time, reservoir cells can start producing HIV, so when an infected person stops taking antiretroviral drugs, their viral load usually recovers within a few weeks.
Stem cell transplants could potentially cure HIV, as they involve destroying a cancer patient’s immune system through chemotherapy and sometimes radiation therapy, then replacing it with a healthy immune system from a donor.
In five of the seven cases where HIV was definitely cured or potentially cured, doctors found donors who had a rare natural defect in both copies of the gene. A specific protein called CCR5, It is found on the surface of immune cells, where most strains of HIV attach. A protein that helps infect cells. Without a functional CCR5 protein, immune cells become resistant to HIV.
The German donor had only one copy of the CCR5 gene, so his immune cells probably have only half the normal amount. The protein. What’s more, he himself only had one copy of the gene. These two genetic factors combined may have increased his chances of recovery, Gaebler said.
Having two copies of the faulty CCR5 gene is rare, occurring in about 1 percent of people with Northern European ancestry, while having one copy occurs in about 16 percent of such people.
“This study suggests that we could expand the donor pool for these cases,” Sharon Lewin, director of the Peter Doherty Institute of Infection and Immunity in Melbourne, Australia, said at a press conference last week.
Interestingly, the man who was treated in Geneva was expected to be cured of HIV, but Announced last year This patient had a donor who had two normal copies of the CCR5 gene, so the transplanted immune cells were not HIV-resistant.
These two recent cases in Europe raise important questions about what factors actually contribute to HIV treatment success.
“The level of protection expected from a transplant would not have been sufficient to prevent viral survival and relapse,” Dr. Stephen Deeks, a leading HIV cure researcher at the University of California, San Francisco, who was not involved in the German man’s treatment, said of the case. “We have some theories that can be tested, so I’m optimistic that we will learn something from this study that will guide the next generation of treatment research.”
Gebler said mixing in HIV-resistant immune cells would certainly greatly increase the success rate of treating the virus with a stem cell transplant, but he said success would not be hindered by a lack of or holes in the safety net, as in the German man’s case.
“We need to understand how the new immune system was transplanted into his body and how it was able to clear the HIV reservoir over time,” he said. “The donor’s innate immune system may have played a key role here,” he said, suggesting that the transplanted immune cells could have attacked the viral reservoir.
The remaining six are either cured or potentially cured of HIV.
Initially, they were known by pseudonyms based on where they received treatment.
- Timothy Ray Brown, aka “The Berlin PatientBrown, an American living in Germany, was treated for AML. Released in 2008which revitalized the field of HIV research. Born in 1966, he was cured of HIV, Died of recurrent leukemia in 2020.
- Adam Castillejo, aka “London PatientMr Castillejo, 44, a Venezuelan man living in the UK, underwent a stem cell transplant for AML in 2016 and stopped his HIV treatment in 2017. He is considered to be cured.
- Mark Franke, “The Düsseldorf patientFranke, 55, who underwent a stem cell transplant for AML in 2013, stopped taking antiretroviral drugs in November 2018. considered cured.
- Paul Edmonds,alias”City of Hope PatientsEdmonds was 63 when he underwent a stem cell transplant for acute myeloid leukemia (AML) in 2019, making him the oldest person to potentially be cured, but he underwent reduced-intensity chemotherapy due to his age. He has been off antiretroviral drugs since March 2021 and will be considered cured if five years pass without viral rebound. In an interview, Edmonds expressed excitement about the new case of a supposedly cured man, saying, “My vision is clear: a world where HIV is no longer a text, but a footnote in history.”
- of “New York PatientThe first woman of mixed ancestry to potentially receive a cure, she was diagnosed with leukemia in 2017 and underwent a stem cell transplant with the addition of umbilical cord blood, which made her less of a genetic match with a donor and broadened the donor pool.
- “The Geneva patientThe man, who is in his 50s, was diagnosed with a rare blood cancer in 2018 and has been off HIV treatment since November 2021. Researchers are remaining cautious about the status of his recovery because his immune cells are not resistant to HIV.
The three friends — Franke, Edmonds and Castillejo — are planning to attend an HIV conference in Munich.
