By Kate Linebaugh
Third-grader Andrew Calabrese carries his backpack everywhere he goes at his San Diego-area school. His backpack isn’t just filled with books, it is carrying his robotic pancreas.
The device, long considered the Holy Grail of Type 1 diabetes technology, wasn’t constructed by a medical-device company. It hasn’t been approved by regulators.
It was put together by his father.
Jason Calabrese, a software engineer, followed instructions that had been shared online to hack an old insulin pump so it could automatically dose the hormone in response to his son’s blood-sugar levels. Mr. Calabrese got the approval of Andrew’s doctor for his son to take the home-built device to school.
The Calabreses aren’t alone. More than 50 people have soldered, tinkered and written software to make such devices for themselves or their children. The systems—known in the industry as artificial pancreases or closed loop systems—have been studied for decades, but improvements to sensor technology for real-time glucose monitoring have made them possible.
The Food and Drug Administration has made approving such devices a priority and several companies are working on them. But the years-long process of commercial development and regulatory approval is longer than many patients want, and some are technologically savvy enough to do it on their own.
Initially, Mr. Calabrese worried about the safety of the do-it-yourself project. He built it over two months, and spent weeks testing. At first, he only tried it out on his son on weekends and at night. Once it performed well enough, he said it felt irresponsible not to use it on his 9-year-old son.
“Diabetes is dangerous anyway. Insulin is dangerous. I think what we are doing is actually improving that and lowering the risk,” Mr. Calabrese, 41, said.
The FDA regulates companies that make and market medical devices but the agency doesn’t have authority over how doctors and patients can use such devices. This means that as long as the people tinkering with their insulin pumps aren’t selling or distributing them, the FDA doesn’t have a legal means to stop it.
More than one million Americans live with Type 1 diabetes, an autoimmune condition in which the pancreas stops producing insulin, a hormone needed to turn sugar into energy. Too much sugar, or glucose, in the blood can lead to long-term complications like kidney failure; too little can cause seizures and coma. The hope for the artificial pancreas is that an algorithm can optimize insulin dosing by processing blood-sugar data generated every five minutes by a subcutaneous sensor.
Medtronic PLC completed a trial in March for its device, called the 670G, which the company plans to submit for regulatory approval in June. Johnson & Johnson plans to start enrolling a clinical trial later this year. About two years ago, at a meeting with Medtronic in which company executives laid out several intermediate products that would be introduced prior to an artificial pancreas, FDA officials responded with a desire for a faster time frame, according to two people familiar with the meeting.
“Biology isn’t quite as easy as controlling the temperature in a room,” said Francine Kaufman, chief medical officer for Medtronic’s diabetes division. She sees do-it-yourself efforts as a sign of the interest in the technology, but distinct from the process of getting a commercial device to market. Dr. Kaufman estimates Medtronic’s submission to the FDA will exceed 100,000 pages and hopes that the device will be approved in 2017.
The home-built project that the Calabreses followed, known as OpenAPS, was started by Dana Lewis, a 27-year-old with Type 1 diabetes in Seattle. Ms. Lewis began using the system in December 2014 as a sort of self-experiment. After months of tweeting about it, she attracted others who wanted what she had.
The only restriction of the project is users have to put the system together on their own. Ms. Lewis and other users offer advice, but it is each one’s responsibility to know how to troubleshoot. A Bay Area cardiologist is teaching himself software programming to build one for his 1-year-old daughter who was diagnosed in March.
The system involves an outdated insulin pump that communicates with a small radio stick connected to a continuous glucose monitor, a computer motherboard and a battery pack. (Insulin pumps are small pager-sized computers that deliver doses of the hormone through a small tube under the skin.) It is an outgrowth of another open-source project where caregivers developed software to remotely monitor blood-sugar levels.
The size of the homemade system varies, and the one that Andrew Calabrese carries has come down from the size of a small shoebox to that of a headphone case. He wears his insulin pump and glucose monitor on his belt.
“It is clearly for people who have some expertise in computer programming,” said Bruce Buckingham, a pediatric endocrinologist at Stanford University who has conducted clinical trials for Medtronic and others developing such systems. “What it shows is that people are anxious to get something going,” Dr. Buckingham said.
The FDA declined to comment on the project but said the agency is working with manufacturers to approve a device.
Sarah Howard became interested after she met Ms. Lewis last year. “My first question was: Was it legal?” said the 49-year-old, who has Type 1 diabetes, as does one of her two sons. “I didn’t want to do anything illegal.”
Afterher husband built the system for her and her son, she said the main benefit is starting each day with her blood sugar in range and not having to wake in the night to check her son’s glucose levels.
It isn’t always smooth sailing. Ms. Howard’s 11-year-old son only uses the device at night. The one time he brought the homemade rig to school, his pump failed. “It doesn’t work every day all the time,” she said.
Mr. Calabrese agrees. “It is not going to be a cure,” he said. That is because insulin dosing for meals is still done manually. And the system remains vulnerable to the problems of current technology, like pump failures and occlusions in tubing.
All that said, Mr. Calabrese says the algorithm is more disciplined. “People aren’t suited for this,” he said. “It is definitely a job for machines.”
http://www.wsj.com/articles/tech-savvy-families-use-home-built-diabetes-device-1462728637
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