I started doing a little digging on this story about Timothy Brown, The Man Who Was Cured Of AIDS. He had a blood stem cell transplant from a donor who had a special genetic mutation that made him resistant to HIV.
Jamie Vernon posted in Scientific American about this case last August. While he is optimistic that we are making huge strides in HIV/AIDS research, he maintains some skepticism that Brown’s path will be The One True Cure.
There are several reasons why Brown’s case is not likely to be translatable to the millions of others whose lives are threatened by this disease.
First, Brown had been highly successful at controlling his infection using antiretroviral therapy. In order to undergo leukemia treatments, he agreed to stop taking his HIV drugs. This led to a dangerous spike in his viral load. Fortunately, after receiving the stem cell transplant, the virus went to undetectable levels and remained so. For the record, no one has ever stopped taking HIV drugs without experiencing a reemergence of the virus.
Second, the risk of dying from the stem cell transplant alone ranges from ~10% to as high as 40%. This is not a risk most would accept given current success controlling HIV infection using antiretroviral drug treatments. Third, tests on Brown’s blood revealed that he was carrying variants of the virus that were capable of infecting white blood cells without relying on the CCR5 protein. No one knows why those viruses never infected the transplanted cells. Finally, Brown experienced neurological and intestinal side effects from the stem cell treatments. These complications led to temporary blindness and memory problems. At one point, Brown was in an induced coma so doctors could deal with his complications. He continues to undergo therapy to recover his balance as well as to restore his normal speaking capabilities.
To summarize, Timothy Ray Brown is what some would call a medical miracle. Despite the rational approach taken by Dr. Hütter, the medical science that “cured” him of HIV and preserved his life relied on some uncontrollable circumstances, like finding a tissue match with the delta32 mutation and avoiding infection of the transplanted cells. Some would say Timothy Ray Brown is simply a lucky guy.
He goes on to theorize how the lessons learned in Brown’s treatment might be applied toward finding a less-risky, more universal treatment for AIDS patients.
Dr. Lawrence Petz, a stem cell transplantation specialist, as well as chief medical officer for StemCyte and president of the Cord Blood Forum, explained cord blood essentially gives doctors more leeway in regards to matching patients with donors and opens the possibility of treating many more people.
Two weeks ago, a patient in the Netherlands was the first to undergo this potentially revolutionary treatment. As was the case with Brown, the transplant was primarily done to address another disease, but doctors specifically selected a unit of cord blood that contained the HIV-resistant gene in hopes of curing that as well. Another similar surgery is scheduled for a patient in Madrid within the month