Doctors in Berlin, working with an American patient with both HIV and leukemia, have declared in a peer-reviewed journal that they believe they have cured both illnesses. It would be the first time an HIV patient has been cured.
The procedure is creating a buzz in the HIV academic community in the United States. Experts in the U.S. call the development encouraging, but warn that years of work remain before the treatment could lead to a general therapy against HIV.
" 'Cured' is a strong word. But this is very encouraging," said Dr. David Scadden, co-director of the Harvard University Stem Cell Institute. "From all indications, there was no residual virus. It's as good an outcome as one could hope."
HIV/AIDS, first recognized in the United States in 1981, was almost always a death sentence until the mid 1990s, when powerful antiretroviral drugs were developed to hold it mostly in check.
"I would call this a functional cure," said Dr. Margaret Fischl, pioneering AIDS researcher at the University of Miami. "It's on the level and a very remarkable case. But would we do this with an HIV patient? No."
The treatment is too radical, its side effects too harsh for general use, Fischl said. Still, it opens new avenues for researchers to create more practical cures, she said.
In 2007, a 44-year-old American named Timothy Ray Brown, who had both HIV and leukemia, was set to undergo stem cell therapy in Berlin to fight his leukemia. But Dr. Gero Huetter and colleagues at Charite-University Medicine Berlin decided to perform a stem cell transplant that also might help against his HIV.
They used stem cells from a donor who had an inherited gene mutation that left his body without the gene receptors involved in contracting HIV, making him naturally resistant to the virus.
On the day of the transplant, Brown stopped taking the antiretroviral drugs that had been keeping his HIV in check. In February 2009 the doctors reported in the New England Journal of Medicine that Brown's HIV had not rebounded in the first 20 months after the transplant.
Still, some doctors suspected, based on experience, that the virus remained hiding in his body. But in the new report this week in the journal Blood, the doctors say that 3 ½ years after the transplant, Brown's cell counts remain in the range of people without HIV.
Brown also shows no evidence of leukemia, the doctors say.
The treatment in Brown's case couldn't be used for the general population, Fischl said, because he first had to undergo intense chemotherapy and full-body radiation to fight his leukemia. The treatments nearly destroyed his immune system — but also left his body receptive to the new, HIV-resistant stem cells.
HIV can be controlled in most patients by using antiretroviral drugs. Doctors would not put them through the debilitating chemotherapy and radiation that Brown received simply to cure HIV.
More than 50,000 cases of HIV are reported in the U.S. each year, and more than 500,000 people in the 34 states that report such statistics are living with HIV/AIDS. Worldwide, about 33 million are living with HIV/AIDS, with 2.7 million new infections each year, the World Health Organization says.