For diabetics in trial, temporary freedom with ‘bionic pancreas’
Stanley Baker can’t remember feeling quite so free in a very long time.
Baker is one of 52 people ages 12 and older with Type 1 diabetes who for five days tested in real-world settings a “bionic pancreas,” designed to take over the job of providing insulin on a minute-by-minute basis when the body’s real organ fails.
“This totally relieves you of managing the diabetes,” said Baker, 76, of Ipswich, Massachusetts. “It was extremely liberating.”
The mechanical device worn outside the body was designed by Edward Damiano, a Boston University engineer who has worked on the technology ever since his 15-year-son was diagnosed with diabetes as an infant. It kept patients at near normal levels in two trials and prevented dangerous blood sugar drops better than standard therapy, according to a report Sunday at the American Diabetes Association meeting in San Francisco.
It is among the first tests of such a system outside of a tightly-controlled setting, according to Damiano, who said the investigators are starting a new, larger trial in four cities Monday and plan to have an improved version of the device on the U.S. market by the end of 2017.
The bionic pancreas is comprised of five parts connected externally to one another and the body. It includes two pumps attached to the abdomen to deliver hormones, a glucose monitor with a wire that runs just under the skin and a computer program that calculates proper doses in a closed-loop system.
Adults using the device, which checks their blood every five minutes, roamed Boston unfettered, eating and exercising normally, ignoring the condition that typically weighs on their daily activities. Adolescents under age 20 given the technology were attending a diabetes summer camp. Both groups were closely monitored 24 hours a day.
“There’s no current standard-of-care therapy that could match the results we saw,” said Damiano. The results were simultaneously published in the New England Journal of Medicine.
About three million Americans have Type 1 diabetes, in which the pancreas stops secreting the hormone insulin used to convert food into energy. Patients typically test their blood several times a day to measure glucose levels, then calculate the amount of insulin they need to inject based on their diet and exercise. High blood sugar can lead to organ damage and death, while too little can trigger unconsciousness or a coma.
The device isn’t being tested on people with the more common Type 2 diabetes, which typically develops in adults and is linked to a sedentary lifestyle. People with Type 2 produce insulin, though their bodies don’t use it properly.
The researchers used commercially available equipment , including a glucose monitor from Dexcom and two pumps from Tandem Diabetes Care, both based in San Francisco. They crafted their own computer algorithm and ran it on an iPhone 4 to wirelessly connect the component parts and calculate how much of each hormone the patient needed.
“It’s constantly adapting to the patient’s ever-changing insulin needs,” said Damiano, who built the device with Firas El-Khatib, also a biomedical engineer at Boston University. “We had to learn and figure out how much insulin you need for the glucose reading it’s getting.”
Other companies, including Medtronic and Johnson & Johnson, are working on similar products. Minneapolis-based Medtronic already sells an artificial pancreas system known as the 530G, which halts insulin delivery for two hours if a patient’s blood sugar falls below a pre-set level.
The bionic pancreas tested by the Boston researchers goes further, by constantly measuring blood-sugar levels and predicting the amount of insulin needed. It is unique because it also administers glucagon, another hormone that causes the liver to release glucose.
Glucagon, which is produced by a healthy pancreas, isn’t routinely given to diabetics, said Sue Brown, an adult endocrinologist at the University of Virginia School of Medicine in Charlottesville, who works with artificial pancreas technology and wasn’t involved in the trial. Understanding the long-term implications of its use is one thing researchers will be looking for in further trials, she said.
Rapid progress has been made in the entire field, Brown said, with additional studies on rival devices used for four to eight weeks in U.S. and European patients coming soon.
The fact that the Food and Drug Administration allowed testing in 52 people, including children, suggests it’s advanced and safe, said Betul Hatipoglu, an endocrinologist at the Cleveland Clinic who wasn’t involved in the study. Many artificial pancreas studies take place in hospitals or controlled settings where food and activities are restricted.
“We are eager to see these kinds of technologies that are going to relieve the pressure from our patients and give them the hope that one day they don’t have to work so hard to achieve the near normal results they need for a healthy life,” she said in a telephone interview.
Baker, the retiree from Ipswich, says he didn’t go crazy in Boston, as some of the other study participants did.
“Some kids were having ice cream sundaes and French fries and forbidden foods, just to see if the device could handle it,” Baker said in a telephone interview. “Normally after a hot fudge sundae you would be pumping yourself full of insulin, but the bionic pancreas handled it.”
The device was consistent, yielding steady blood sugar readings day after day, said Steven Russell, one of the lead authors from Massachusetts General Hospital’s Diabetes unit. Few people can maintain that kind of control themselves with the tools currently available, he said.
Christopher Patrick Herndon, 13, said the experience at the summer camp was like a dream. The ninth grader from Newburyport, Massachusetts, still remembers his diagnosis before Christmas four years ago.
“It was like I was back to normal,” he said by telephone. “It took away everything.”
Herndon noticed the difference immediately. He didn’t have to sit out of activities because of blood sugar swings, and he often felt better than his peers at camp who didn’t have the device, he said.
Without the device, “if my blood sugar goes low, I have to take juice and wait,” he said. “When it’s high, I will talk really fast or get tired and jittery. When I’m low, I’m tired and woozy.”
While on the bionic pump, Herndon said, he ate more and worried about his carbohydrates less. The youngest of study participants, he said he works hard to control his blood sugar levels. He’s looking forward to more help.
“I’d love a product like this.”