Diabetes breakthrough nears with artificial pancreas

MINNEAPOLIS — The discovery of insulin almost a century ago was one of the most remarkable achievements in medical history, transforming a deadly disease into a manageable one. Now diabetics are on the cusp of another breakthrough, one that could ease the endless task of manually testing and adjusting their blood sugar levels.

Medtronic has filed for US approval of the first artificial pancreas, a device the size of a smartphone that wirelessly connects an insulin pump and glucose monitor. The equipment, which remains outside the body, can take over for the malfunctioning organ that’s supposed to naturally produce insulin, the hormone that converts blood sugar to energy.

While innovations in recent years made monitoring and injecting insulin easier, the potential approval of the MiniMed 670G would mark the first time that diabetics could turn over part of their daily routine to a machine. It measures blood sugar every five minutes and automatically administers or withholds micro-doses of insulin to keep patients in their target range.

“Patients are working 24 hours a day now,” said Dr Richard Bergenstal, executive director of Park Nicollet’s International Diabetes Center in Minneapolis, who led the trial. “We want them to get control without spending every hour of the day worrying about their diabetes or preparing for the next event.”

CHASING HIS GOAL

Mr Les Hazelton welcomed the help. The 59-year-old marketing executive from Minnetonka, Minnesota, was one of the first patients enrolled in Medtronic’s trial for the technology. An avid bicyclist who finds it easy to avoid sweets, Mr Hazelton nonetheless felt he was always “chasing” his blood sugar with insulin rather than getting ahead of it. Though he checked his levels seven times a day, he never in 17 years as a type 1 diabetic hit his blood sugar goals until he enrolled in the study.

“It was totally mind-blowing,” he said. “I like being in better control of my body and my disease. The more I know about what’s happening right now, the better I can manage it.”

Few patients maintain their blood sugar levels on their own. Less than 30 per cent of adults with type 1 diabetes, the most severe form, meet the standards for blood sugar control, Dr Bergenstal said. Younger patients do worse, with studies showing 75 per cent of teenagers fail to meet the targets and reduce the risk of complications — from infections and organ damage to heart disease and coma.

Diabetics walk a fine line when it comes to their blood sugar. It can fall too low if treated too aggressively with insulin, causing symptoms including heart palpitations, fatigue, seizures, blurred vision or fainting.

CRUISE CONTROL

Medtronic’s application to the US Food and Drug Administration is based on the experience over six months of 124 patients who turned over most of their disease management to the artificial pancreas technology. The equipment, which continuously monitors blood sugar and administers insulin with a pump, is more like cruise control than a self-driving car. The patients actively used the technology, known as a hybrid closed-loop system, 84 per cent of the time.

“This was them, in their homes, going about their lives,” said Dr Francine Kaufman, chief medical officer and head of diabetes at Medtronic. “There was no remote monitoring. The closed loop is running the train now.”

The system includes three components: A glucose sensor that’s attached to the body and measures sugar levels just under the skin; an insulin pump that’s strapped to the waist; and an infusion patch with a small needle that’s connected to the pump with a catheter and delivers the insulin.

FDA GUIDANCE

Medtronic, based in Dublin and run from Minneapolis, has been working on the technology since it bought MiniMed for US$3.7 billion (S$5.0 billion) in 2001. The effort got a boost in recent years from an unexpected source: the FDA. The agency, criticised for stringent demands that led many companies to introduce novel medical devices abroad first, reached out to the company and its peers to help guide development of the technology.

“We have really tried to make this a major priority,” said Ms Stayce Beck, the FDA’s branch chief for diabetes diagnostic devices, who has spent hours meeting with companies, researchers, patients and activists.

The FDA had other surprises in store. It didn’t require that the new technology control blood sugar better — or even as well as — the older technology. Instead, the agency was open to any number of improvements that would make a patient’s life better, Ms Beck said.

LOWER BLOOD SUGAR

The trial showed Medtronic’s automatic approach performed better than manual fine-tuning, even among patients who could deftly tweak their insulin levels. At the start of the study, the patients had an average blood sugar level of 7.4 using the A1C test, above the target of 7 or less for most diabetics. At the end of the trial, the average was 6.9, with 58 per cent of patients getting to the goal. There weren’t any malfunctions, no one got extremely high or low blood sugar levels, and no one passed out or was hospitalised, Dr Bergenstal said.

Patients using the technology still have some obligations. They must recalibrate the device with a traditional finger-stick reading every 12 hours; the glucose sensor must be changed every seven days; and the insulin pump must be refilled every three days.

“The work isn’t gone, but it seems to be a lot less,” Dr Bergenstal said.

The trial participants didn’t want to give up the artificial pancreas once the study was completed. A group went to the FDA to ask for extended access to the device, and the agency brought the request to Medtronic. The study is now in an extended review period, with more than 100 volunteers, including Mr Hazelton, sticking with the equipment. Medtronic expects the FDA to rule on the device within a year. BLOOMBERG