London man is second person to achieve sustained HIV remission after stem cell transplant
A man in London became the second person to be potentially cured of HIV after undergoing a stem cell transplant, though experts warned it does not mean there is a cure for HIV and the treatment is not suitable for most patients.
The unnamed patient underwent allogeneic hematopoietic stem cell transplantation (allo-HSCT) for Hodgkin’s lymphoma and has remained in HIV remission for at least 18 months after ceasing HIV treatment, researchers reported in Nature.
In addition to undergoing chemotherapy, the man was treated with cells from a patient with two copies of the CCR5-delta 32 genetic mutation, which prevents HIV from entering human cells.
It is the same technique used on the so-called “Berlin patient,” a man named Timothy Brown who also received CCR5-delta 32 donor cells during two transplants in 2008 while being treated for acute myeloid leukemia and has remained in remission for more than a decade. CCR5 is a commonly used HIV receptor.
Infectious Disease News Chief Medical Editor Paul A. Volberding, MD, professor of medicine and director of the AIDS Research Institute at the University of California, San Francisco, called the new report “exciting” and said it “opens considerations of how such an approach may be possible for other patients.”
“It is important to realize, however, that transplantation continues to carry substantial risk and is far too expensive for those parts of the world most affected by the HIV epidemic,” he cautioned.
“Still, the concept that the intentional use of cells naturally protected from HIV infection by the lack of the CCR5 receptor used by most HIV virions opens the possibility that other approaches such as gene editing may also prove useful,” Volberding said. “We look forward to more information about ‘the London patient’ and of course longer term follow-up to see if his remission continues and becomes a cure.”
In the new report — the results of which were presented at CROI — Ravindra K. Gupta, PhD, from the University College London, and colleagues said that the man ceased ART 16 months after transplant and has remained in remission for 18 months since then. He had been diagnosed with HIV in 2003 and was on ART since 2012.
The treatment was different from Brown’s in that the London patient received just one transplant, not two, and was treated with less intensive chemotherapy, Gupta and colleagues said.
“Although at 18 months post-treatment interruption it is premature to conclude that this patient has been cured, these data suggest that single allo-HSCT with homozygous CCR5-delta 32 donor cells may be sufficient to achieve HIV-1 remission with reduced intensity conditioning and no irradiation, and the findings further support the development of HIV remission strategies based on preventing CCR5 expression,” they wrote.
Saira Butt, MD, assistant professor of clinical medicine and infectious diseases program director at Indiana University School of Medicine, also called the report “exciting,” but said there are no immediate clinical implications and the treatment is suitable only for HIV patients with blood malignancy who meet the criteria for a stem cell transplant.
“For now, there is no cure for HIV. It is a chronic condition,” Butt told Infectious Disease News. “[The] message for the patients is: Keep taking your ART.”
Carlos del Rio, MD, past chair of the HIV Medicine Association and chair of the department of global health at Emory University Rollins School of Public Health, put the outcomes of the two patients into further perspective.
“These would be two patients cured. There are 35 million infected and living with HIV,” del Rio told Infectious Disease News. “We need to continue cure research to find an intervention that is feasible and scalable. This one is not.” – by Gerard Gallagher
Gupta RK, et al. Abstract 29LB. Presented at: Conference on Retroviruses and Opportunistic Infections; March 4-7, 2019; Seattle.
Gupta RK, et al. Nature. 2019;doi:10.1038/s41586-019-1027-4.
Disclosures: The authors, Butt and del Rio report no relevant financial disclosures. Volberding reports being on a data and safety monitoring board for Merck and having a cure grant from amfAR.