A 12-year-old boy with HIV and leukemia has died after undergoing the first-ever attempt to cure both diseases with a cord-blood transplant, the Minneapolis StarTribune reports. Eric Blue, from Alexandria, Louisiana, died July 5, two and a half months after a team at Minnesota’s Amplatz Children’s Hospital gave him a bone marrow transplant derived from cord blood. The transplanted cells were extracted from the placenta of a baby carrying the rare genetic abnormality known as CCR5Δ32 that confers natural resistance to HIV infection.

Timothy Brown, the famed “Berlin Patient” who became the first person to be cured of HIV, received a bone marrow transplant with the same genetic abnormality, which is found in less than 1 percent of the population. His medical team was able to find a matching donor who had the CCR5Δ32 abnormality. Because finding such a match is exceedingly improbable, and because cord blood requires less-specific genetic matching, the Minnesota team hoped that using it as a source for the transplant would make a bone marrow transplant cure for HIV available to more people.

Blue died of complications from graft-versus-host disease, which is a precarious period following a bone marrow transplant when the newly transplanted immune cells attack the body’s tissues.  His death highlights the risky nature of bone marrow transplants and why they are not feasible as a means of curing HIV in anyone other than those who would require one to survive an imminently fatal disease such as leukemia.

“He was incredibly brave and courageous, and understood he was participating in something historic,” Michael Verneris, MD, a transplant specialist at the university who was one of Blue’s physicians, told the StarTribune.

Signs suggest that, had he survived, Blue would have been functionally cured of HIV. After his antiretrovirals were discontinued, tests did not detect the presence of the virus in his body. Researchers say these findings are still inconclusive, however.

“The promise we made to the child…was that we were going to learn from this, and we still are learning,” Verneris told the StarTribune. “This is the first step in many, [and] hopefully we’ll be able to really improve the outcomes of not only people with HIV but people with leukemia through understanding these processes better.”

To read the StarTribune story, click here.