Transcript for Doctors Using HIV to Treat Cancer
tonight about a big breakthrough in the treatment of cancer, using hiv as a weapon against cancerous cells. The treatment is being presented now at the american society of hematology, only a dozen patients have tried it. But listen to what happened to one little girl. Here's abc's chief health and medical editor, dr. Richard besser. Reporter: Emma whiteheads leukemia seemed undefeatable. No treatments left. And she was only 6. Then, in april, a last gamble. Using hiv to cure, not kill. Doctors took out millions of emma's disease-fighting white blood cells then used genetically altered virus which is great at getting into human immune systems, to change those cells into targeted cancer fighters. Emma's cells went back in and destroyed the cancer. Dr. Stephan grupp is a pioneer using hiv to infiltrate the immune system. All of the things that make the hiv virus able to cause disease have been removed from this particular virus, so, its only purse is to put a gene in a cell. For me it's incredible. Reporter: Here's emma just eight months later. Doctors can't find any remaining cancer cells. She is in a complete remission. She has no leukemia in her body for any test that we can do. Even the most sensitive tests. She has tons of energy. She's doing wonderful right now. This treatment was a miracle. Reporter: Emma is counting the days till christmas. Her parents are busy counting their blessings. Now, the treatment does wipe out part of her immune system, so, she has to receive medication once a week to prevent infection. But she's feeling strong and she's back in the second grade. Oh, it's so wonderful to see her like that. What about the other of the dozen now just one dozen who had it, were they successful? Reporter: Seven of them had a great response. Three of them in complete remission. Not everyone. Researchers are looking to see, why does it work in some but not in others? The idea of using a virus to deliver treatment for a disease is absolutely fantastic.
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