"It is like a dream for a diabetic. It takes away the responsibility. It takes away the high blood sugar and the low blood sugar. It prevents damage to the body and it makes you feel better all the time."
The Newburyport, Massachusetts, 8th-grader usually wears a standard insulin pump and he got a real-life comparison when he had to give up the new device after five days and go back to the old pump. "When I wasn't wearing it I had to sit out a lot of activities because my blood sugar was low. It was frustrating," he said.
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Life for someone with Type 1 diabetes revolves around testing blood sugar and thinking about every single thing they eat. "At camp, we start the day out checking our blood sugar after morning wake-up," Herndon said. "The counselors give us menus, we count our carbs, add them up and then take insulin shots or set our pumps to deliver a bolus of insulin." Only then do they eat.
After breakfast the campers can play sports — Herndon plays basketball, runs cross-country and plays lacrosse at school — but have to check to make sure the exercise hasn't lowered their blood sugar too much. Then it's the same routine of checking blood sugar, estimating how much they'll eat in carbohydrates for lunch, delivering insulin and, finally, eating. And another round comes at dinner.
"You have to face this 24 hours a day, seven a week. There is no vacation from it," said Kristina Herndon, Christopher's mother.
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About 5 percent of the 29 million Americans with diabetes have Type 1 diabetes.
Diabetes is a condition in which the body cannot process blood sugar properly. Type 1 diabetes is an autoimmune disease, caused when the body mistakenly destroys pancreatic cells that produce hormones like insulin and glucagon that control blood sugar. High glucose levels damage tiny blood vessels, which in turn can lead to blindness, heart disease, stroke and kidney failure. People can lose toes, feet or legs to amputation.
When levels fall too low, patients can pass out and even die.
"It is just fiendishly difficult to control the blood glucose as well as we know it needs to be," says Dr. Steven Russell of Massachusetts General Hospital in Boston, who's been working with Damiano and others on this project for years.
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"You are constantly at risk of low blood sugar, which can be acutely dangerous. It is hard for people to appreciate how hard this actually is."
The team's been working on making an artificial pancreas for years, and the first human studies started in 2008. Their device monitors blood sugar — standing in for the fingerprick test that people with diabetes must do many times a day. It delivers insulin when needed and in the right amounts — something diabetics must do several times a day either with a syringe or by pressing a button on an insulin pump.
And it does something extra — it delivers another hormone called glucagon, which brings blood sugar back up when it's too low.
During the last trial, the team tested the artificial pancreas on patients in the hospital. They wanted them still and resting so their blood sugar levels didn't fluctuate too much. And at that point they needed to be near a laptop computer because it takes complicated software to calculate how much insulin someone needs from moment to moment.
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What made the wearable, bionic device possible was the invention of the smartphone, says Damiano. It was specifically the iPhone 4, with a low-energy Bluetooth signal that could be used to help the various components of the device communicate.
"The iPhone is a perfect platform. We could not have done this without (Apple co-founder) Steve Jobs," Damiano said. Smart phones are powerful computers that people can carry with them—perfect for coordinating the components of the artificial pancreas.
The system is still a bit clunky. The insulin pump itself attaches to a quarter-sized glucose monitor implanted under the skin of the abdomen. A phone-sized external pump is stuck to the abdomen with an adhesive. A second pump delivers the glucagon, and it's all controlled by the iPhone.
In two separate experiments, Damiano and Russell's team tested the device on 20 "free-range" adults and 32 teenagers at a special summer camp for youth and children with diabetes. The results surpassed anything the researchers had hoped for, they reported in the New England Journal of Medicine.
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"The system was able to bring everybody into the range that reduces complications," Russell said. "Not just half of them. Not just three-fourths of them. Everybody."
No one had a hypoglycemic crash. "There's no current standard-of-care therapy that could match the results we saw," Damiano said.
The next step in trials starts on Monday, when 10 patients will try an even more challenging test at Massachusetts General Hospital. They'll wear the device and use it in truly real-life conditions, living and working normally without a nurse hovering nearby.
Their blood sugar readings will be sent wirelessly, via the iPhone, to be monitored miles away at the hospital. But there will be no intervention unless it starts to look like an emergency.
Thirty other patients are enrolled at the University of Massachusetts Medical School, Stanford University and the University of North Carolina. And they'll try it out in younger campers, this time on the 6- to 11-year-olds.
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Kristina Herndon says she can't wait for Christopher to get another chance, too. "We'll be the first ones with our hands raised for a new trial," she said.
Damiano is in a hurry. His son, now 15, has Type 1 diabetes and he wants a marketable device ready for when the boy starts college. "The most practical difference would be not having to think about diabetes 24/7, not having to constantly make decisions about things that those of us without Type 1 never have to think about," he said.
"Another real problem that would be relieved is the fear — fear of going to bed at night and not knowing if your blood sugar level will drop dangerously low while you sleep."
The team, working with funding from the National Institutes of Health and private donations by groups including the Leona M. and Harry B. Helmsley Charitable Trust, is working with an unnamed device maker to get the two pumps combined into one.
"We still have a couple of years of work ahead of us," Russell said. Getting the price down will be a big factor. The glucagon alone costs $160 a day right now. "We don't want this to be a niche thing. We want this to be available to everybody," he added.
For Christopher and his mother, Kristina, it would mean a good night's sleep.
"My mom won't have to worry at night," Herndon said. "She won't have to check my blood."
—By Maggie Fox, NBC News