If you saw 7-year-old Emily Whitehead today, you might find it hard to believe that she was fighting a deadly battle against acute lymphoblastic leukemia just last spring.
The Pennsylvania resident was only 5 years old in 2010 when she developed the blood disease, a particularly aggressive form of the cancer that is usually treated with chemotherapy, according to Everyday Health.
In fact, Whitehead had received chemotherapy twice and had relapsed both times, reported the New York Times. At that point, parents Kari and Tom were looking for one last hope after doctors had exhausted traditional options.
They found that opportunity at Children's Hospital of Philadelphia, where doctors were working on an experimental treatment that used a bio-engineered version of Whitehead's T-cells, a type of white blood cell, to "reprogram" her immune cells to attack and destroy the leukemia, according to the Times.
While the treatment itself caused Whitehead to endure extreme swelling and a fever that reached 105 degrees, leaving her unconscious, it eventually began working to destroy cancer cells. That was in April, and she is now considered to be in full remission.
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"We've checked her bone marrow for the possibility of disease at two points," said Dr. Stephan Grupp, pediatric oncologist and director of translational research at the Children's Hospital of Philadelphia, in a video filmed at the facility (above). "We checked her three months and now six months after the treatment. She has no disease whatsoever."
Whitehead is only one of a dozen patients with advanced leukemia—and one of two children—to receive this treatment, which was developed at the University of Pennsylvania, according to the Times.
While all of the patients have yet to see such positive results from the treatment, known as CTL019 or CART19 therapy, "Our goal is to have a cure, but we can't say that word," Dr. Carl June, who leads the research team, told the Times.
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The drug company Novartis has even invested in the research, committing $20 million to build a research center on the UPenn campus, reports the Times.
"Right now we're feeling hopeful, really hopeful," says Kari in the video.
"We just stick together as a team," says Tom in the video, "and she's definitely our hero."
Emily returned to school this fall. She's in the 2nd grade and even plays soccer.
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