Researchers have announced that a woman who received a stem cell transplant to treat her acute leukemia and waited three years to stop antiretroviral therapy shows no sign of HIV 14 months later. She becomes only the third reported case, and the first woman, to show no signs of HIV following such a transplant. The study investigators caution that it is too early to be certain the woman is cured, but remain hopeful.
Timothy Brown, the Berlin patient, was reported to be cured of HIV in 2008. He was followed by Adam Castillejo, the London patient, who remains HIV-free after a stem cell transplant in 2012. Castillejo was part of amfAR’s ICISTEM research consortium, which enrolled an international cohort of patients with cancer and HIV who had received stem cell transplants.
Describing the new case at the Conference on Retroviruses and Opportunistic Infections, February 15, the researchers explained that in undergoing the transplant, the mixed-race woman had received stem cells from umbilical cord blood instead of the more typical adult stem cells. As with Brown and Castillejo, the donated cells contained a genetic mutation – CCR5 delta32 – rendering them resistant to HIV infection. In addition to the cord blood transplant, she also received adult stem cells from a relative who lacks the CCR5 delta32 mutation.
The woman, who remains anonymous but has been dubbed the New York patient, was part of an observational study funded by the National Institutes of Health (NIH) and led by Dr. Yvonne Bryson of the University of California, Los Angeles, and Dr. Deborah Persaud of Johns Hopkins University, Baltimore. The IMPAACT P1107 study followed up to 25 participants living with HIV who had received a stem cell transplant using cord blood cells with the CCR5 mutation.
While NIH funded the newly reported case, this approach to stem cell transplantation has been a recurrent theme in amfAR’s search for a cure for the past 10 years. Dr. Koen van Besien, director of the stem cell transplant program at NYP-Weill Cornell College of Medicine in New York, and Dr. Lawrence Petz, founder of the cord blood bank that was the source of the cord blood stem cells, presented at an amfAR think tank in 2012. amfAR subsequently funded research on a similar case, applying the same combination cord blood-adult cell approach pioneered by Dr. van Besien, using cells from Dr. Petz’s cord blood bank and adult stem cells from a related donor. The case was published in 2015, and although there was no detectable HIV after the transplant, unfortunately the patient succumbed to cancer before it could be more definitively established whether he’d been cured.
Researchers are hopeful that, since cord blood is more widely available than adult stem cells and doesn’t require an exact match, the case may expand access to remission or cure to a somewhat wider pool of people living with HIV.
“Any new case like this is very welcome news and we are heartened by these findings,” said Kevin Robert Frost, amfAR’s chief executive officer. “But since this approach remains confined to those who need a stem cell transplant for the treatment of cancer, the urgent need remains for a cure that can be made available to all who need it, and we continue to vigorously pursue that goal.”