A bionic pancreas designed to take over blood sugar control in people with type 1 diabetes got patients to near normal levels and prevented dangerous drops better than standard therapy in two demanding five-day trials.
Adults given the device roamed the Boston area where it was tested unfettered, eating and exercising. They fared best with the bionic pancreas that checked their blood every five minutes and administered insulin and another hormone as needed.
The pancreas was tested in 20 adults, who can be exquisitely sensitive to insulin, and 32 adolescents, who often need twice as much because of their growth and hormone levels. Both had better blood sugar control with the device than with their normal care, according to a report presented today at the American Diabetes Association meeting n San Francisco.
“There’s no current standard-of-care therapy that could match the results we saw,” said senior author Edward Damiano, a Boston University engineer who has worked on the technology since his 15-year-son was diagnosed with diabetes as an infant.
The investigators are designing a final trial on the bionic pancreas and hope to have an improved version on the U.S. market by the end of 2017, Damiano said by telephone. The device is made up of five parts connected to each other and the body externally. 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.
About three million Americans have type 1 diabetes, when 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.
Stanley Baker, a 76-year-old from Ipswich, Massachusetts, got type 1 diabetes after a bad bout with the flu in 1988. He said he can’t remember the last time he felt so free.
“I tell you, as a diabetic, you are always thinking about your blood sugar,” he said. “This totally relieves you of managing the diabetes. A lot of the concern I have on a regular basis was gone. It was extremely liberating.”
The researchers used commercially available equipment , including a glucose monitor from Dexcom Inc. and two pumps from Tandem Diabetes Care Inc., 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.”
Rival companies, including Medtronic Inc. 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.
The entire field has been making rapid progress, 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 U.S. 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 he’s attended for the past several years 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 those enrolled in the study, 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.”