Trial of artificial pancreas gives diabetes patients a break

For Terra Hillyer, who has Type 1 diabetes, enrolling in a clinical trial for a new medical device called the artificial pancreas provided a glimpse of what life might be like without the constant checks of blood sugar levels and infusions of insulin that currently mark her days.

“The first thing I do when I wake up is check my blood sugar,” Hillyer says. “It is the background noise of my life.”

Except for one day recently, when the mother of two checked into the Sansum Diabetes Research Institute in Santa Barbara. There, under medical supervision, she allowed herself to be hooked up to an experimental device that might help turn back the clock to the time before she was diagnosed with Type 1 diabetes at the age of 17.

In people with Type 1 diabetes, the pancreas fails to produce insulin, a key hormone in the regulation of blood sugar. As a result, patients need to carefully monitor their blood sugar levels and administer insulin on their own. The artificial pancreas is designed to manage the administration of insulin and control the user’s blood sugar automatically -- meaning that the participants, for the first time since childhood, could put their blood sugar readings out of their minds.

“I called it my diabetes spa day,” Hillyer said with a laugh. The artificial pancreas -- made by Animas Corp., a unit of Johnson & Johnson -- is really a combination of two state-of-the-art technologies in diabetes management: the continuous glucose monitor, which measures blood sugar regularly, and the insulin pump, which can be programmed by its user to deliver a predetermined amount of insulin.

Currently, people using these devices have to read their glucose monitor and then make a decision about how much insulin they need. And they must do this constantly -- potentially dozens of times per day, depending on their diets, activity levels and other factors. Sleep is a problematic time, since users cannot monitor their levels.

The artificial pancreas removes these burdens: the readings of the glucose monitor are passed to the insulin pump, and an onboard computer determines the appropriate insulin dose. Animas’ device also utilizes a proprietary algorithm that aims to predict the future course of a user’s blood sugar, allowing insulin levels to change well in advance of any complications.

While testing the device in Santa Barbara, volunteers were able to observe how the artificial pancreas took over the management of their blood sugar.

“It was fascinating to see how the program thinks,” said Kirk Martin, another volunteer. “I’m sitting there turning my life over to this machine, and you say, ‘I hope it’s right.’ But you can see on the monitor that it’s right, so you acquiesce.”

The results from the Animas trial, presented Monday at the annual meeting of the American Diabetes Assn. in Philadelphia, were positive, though limited in scope. The researchers showed only that the device was able to keep the participants’ blood sugars within an acceptable range, without any safety risks, for 24 hours.

According to Dr. Steven Russell, who is working on an artificial pancreas at Harvard Medical School and was not involved in the Animas trial, the study is important because it represents a large investment in artificial pancreas development by a major medical device company.

Animas is one of several companies and academic research groups presenting promising results from artificial pancreas studies at the diabetes meeting, Russell said. “This is a field that’s picking up momentum,” he said.

Just last week, Medtronic Inc. filed an application with the FDA seeking approval of its own device that shuts off insulin administration if the user’s blood sugar gets too low. The device is already approved in 50 countries, and if it’s approved in the U.S., it could pave the way for a new wave of tools to manage diabetes like the one Animas is developing, said Aaron Kowalski, assistant vice president for research at the Juvenile Diabetes Foundation, which helped fund the Animas trial.

“The more companies involved, the better,” Kowalski said. “Ultimately, for patients to benefit, this needs to be commercialized.”

For people with diabetes who participate in these trials, the experience can be bittersweet.

“It’s frustrating that this device is available and there are so many people that could benefit from it,” Hillyer said. “But I also think the work is really encouraging, and it gives me hope.”

Martin agreed, saying that he is very proud to be participating in the research process that might one day change his life for good. “But am I disappointed that I can’t have it now? Yes, yes I am.”

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