A stem cell transplant in 2007 brought hope to people living with HIV/Aids like no other event before it. In that year, 40-year-old Timothy Ray Brown got cured of HIV!

Research is on-going on various fronts to prevent, treat and cure HIV and Aids. Stem cell transplantation is one of them.

Brown was diagnosed with HIV in 1995. He managed his illness by taking antiretrovirals for more than a decade. Then he received staggering news: he suffered from acute myeloid leukemia, a blood cancer that is fatal if left untreated.

Since the start of the HIV epidemic 30 years ago, it has been discovered that about 1% of Caucasians have a natural immunity to HIV because their cells lack the CCR5 protein that enables HIV to enter healthy blood cells. So, when doctors decided that Brown needed a stem cell transplant as treatment for his leukemia, they opted for a donor who is immune to HIV. Luckily for Brown, such a donor was found.

Brown’s own immune system was wiped out with radiation and chemotherapy, and then he was given the donated stem cells to rebuild an immune system in his body. He suffered numerous complications that made it necessary to stop the ARV treatment. His HIV rebounded but ARVs were restarted immediately and after three months the HIV infection was undetectable. His blood cancer returned and he received a second stem cell transplant from the same donor in 2008. Although he was very ill at this stage, it was found that the HIV remained undetectable. Eventually the blood cancer was cured and the HIV still remained undetectable, even after he stopped taking antiretrovirals. He was pronounced cured of HIV – the first person that has ever happened to.

Today, more than four years after the transplant, Brown is still free of both illnesses.

Implications of the successful stem cell transplant

    • Probably the most important outcome of Brown’s successful stem cell transplant is that for the first time both researchers and sufferers could believe that HIV can be cured! It has given new impetus to the many people conducting research on finding a cure for HIV.
    • Unfortunately the same treatment is not readily available to the 34 million people living with HIV. Stem cell transplants are dangerous and expensive, and suitable donors of HIV-immune stem cells are scarce.
    • The successful transplant demonstrated the critical role CCR5 plays in maintaining HIV-1 infection and the progression of the disease, thus inspiring renewed research on treatments that target CCR5. Scientists are trying to introduce artificial mutations that mimic those in people who are naturally immune to the virus. They hope that the mutations will proliferate and replace the immune system of the person living with HIV.
    • Stem cell transplants as treatment for HIV is still in its infancy, but there is growing optimism that a cure is possible within our lifetime.

 

Sources
http://defeathiv.org
http://en.wikipedia.org
http://seattletimes.com
http://www.dailymail.co.uk
http://www.fhcrc.org
http://www.nejm.org