A Technology Breakthrough in Diabetes Care
By Gary M. Kaye, Chief Content Officer, Tech50+ www.tech50plus.com)
Diabetes sucks. I won’t mince words. The disease has dire consequences. It’s the disease that keeps on giving. It gives you kidney disease. It gives you retinopathy. It gives you neuropathy. It gives you amputated limbs. It can devastate your other organs and circulatory system. It can be incredibly difficult to monitor and control. And more than 29 million Americans have it. According to one recent study between one-third and one-half of U.S. adults are either diabetic or pre-diabetic. And not only is the cost to the sufferers devastating, but the impact on the health care system runs over $250 billion each year.
It’s no wonder that diabetics have been closely watching the development of biomedical devices that would help them monitor and control diabetes. Most need to prick their fingers four or more times a day to measure their blood glucose. Some can control the disease with pills, others need insulin injections. And often they are plagued with huge blood sugar swings from highs to lows which themselves can be dangerous, or deadly.
Now, for the first time, the FDA has approved what’s called a “closed loop system” which continuously monitors a patient’s blood glucose and delivers micro-doses of insulin to keep that level in check. The system has also been referred to as an “artificial pancreas”, a phrase that does not sit well with the American Diabetes Association since the device only performs one of the many functions of that organ.
The two major components of the system, the continuous blood glucose monitor, and the insulin pump have each been around for years. Dean Kamen invented the insulin pump in 1973 and first began marketing it in 1976. Dexcom first brought continuous blood glucose monitoring to market in 2006. But only now have the two been combined to work together. This has not been an easy problem to solve, and it’s taken sophisticated algorithms and sensors to make it work right. That’s because insulin takes a while to get into the bloodstream while consuming foods can have an almost instant impact on blood sugar levels, so you are always playing catch up.
The first FDA approved device is the Medtronic MiniMed 970G. So far the device is only approved for Type I diabetics, though they constitute only about 10% of the nation’s diabetics. Type I diabetics generally require what’s called full insulin replacement, in other words their bodies simply don’t make insulin. Only a fraction of Type II diabetics are in the same boat – many can keep in control by exercise, diet, and medication.
We spoke with Mike Hill, Vice President for Global Sales at Medtronic who says the MiniMed 670G hybrid closed loop system is a major step forward, but it’s still not the goal,
From our point of view, a full closed loop system would be one that is constantly monitoring glucose, and then the system is automatically adjusting and delivering basal and bolus insulin so that it wouldn’t require any patient interaction beyond wearing the devices. That would be a full closed loop. The mini-med 670 G is called a hybrid-closed loop because the pump does some of the automation but the system does require patient interaction. Our current hybrid closed loop system has a continuous glucose monitor, so it’s checking glucose readings basically every 5 minutes and then the system will automate the basal rates, the background insulin. It’ll take that up or down based on what your glucose level is with a target of 120. It’ll take the background insulin up or down to bring you to the fixed target of 120.
In other words, says Hill, the patient still needs to intervene by giving himself shots and periodically taking manual blood glucose measurements to keep the system calibrated.
As to the nickname “artificial pancreas”
We don’t talk about an artificial pancreas. We used to several years ago use that terminology and that’s why for example you’ll still see the FDA and other people using it but we received feedback from clinicians, patients, and other folks that a pancreas does more than just deliver insulin, or monitor glucose, which from Medtronic’s point of view, is what our systems do, so the implication was more than it could possibly be. We talk about a closed loop, basically closing the loop between measuring glucose and delivering insulin.
Hill notes there are two different families of insulin: basal, which is the long acting background insulin sold under names like Levemir and Lantus, and bolus, a short acting insulin such as Novolog and Humalog. Hill explains,
So what we call basal insulin is the background insulin. It’s the low steady rate that allows you to bring basic glucose into the system. Bolus is when you need a specific larger amount of insulin to cover a specific event. So you eat a meal, as your body digests the food you’re going to get a surge of glucose in your blood as your intestines are absorbing it. If you don’t have extra insulin in your body times with when that food is digested, your going to have really high glucose levels for a long time. That can have both short and long-term complications. High sugar levels in the blood are damaging to the body.
Hill says a major advantage of the closed loop system is that it automates what has been a very complex process,
You’re constantly making all these decisions every day about what you’re eating, are you exercising, are you sick or not, how much insulin did you take before, when are you going to bed, and you’re trying to put all that info together and then make decisions about what you should do with insulin. That kind of complex repetitive mass based decision making is not what humans are great at. We do it. But it’s frustrating and challenging. So the benefit of starting to automate these things is because the system is checking glucose every 5 minutes and then the system is making a decision every 5 minutes, it can automate a ton of small decisions that will lead you to have a better outcome. In that example, you could put a small amount of insulin on board and eat, not whatever you wanted, but choose a different type of meal, and if you put in too much or too little insulin, the system is going to see where your blood sugars are going and then dial up or down the insulin to match. Basically, it tightens up every decision. The only way for you to replicate that yourself is taking finger sticks every 5 minutes and giving little bits of insulin and that sort of thing which is far more maintenance than you’d want to do. So, in short, the system can give you better control with fewer burdens so people are getting both clinical benefits and quality of life benefits.
While Medtronic is the first to bring a closed loop system to market, there are a number of other companies who are lined up for the FDA approval process and are expected to have their own devices commercially available over the next two years. The next one up may well be the iLet from Beta Bionics, which began as a joint project by Boston University and Massachusetts General Hospital.
Doctor Stuart Alan Weinzimer is a pediatric endocrinologist who is currently supervising the closed loop clinical trial at Yale-New Haven Medical Center. He says the early results are very positive.
In the initial pivotal study we rolled 124 people, 94 adults, 30 adolescents, it was not a randomized controlled study, everybody got the system. After a 3-month period, with very significant reductions in A1C and concomitant reductions in hypoglycemia (low blood sugar) exposure which is really the best of both worlds…In the old days you had to lower A1C if you increased your risk of hypoglycemia but here we seem to achieve both. After 12 thousand patient days of use there weren’t any episodes of severe hypoglycemia or DKA. It really was quite safe. Most people who are familiar with these devices know it’s not a completely automated system; it’s a hybrid system. For meals, you still have to count your carbs but then the system will have a variable that will work based off its sensors. In between meals and overnight, it’s really good at regulating despite whatever would happen at night, whatever you would eat or whatever exercise you did during the day, the nighttime were really quite good. People would tend to wake up in the morning pretty close to goal blood sugar. Starting off the day at 140, you don’t lose half the day trying to get there.
Dr. Weinzimer says the systems will get even better as sensor technology improves. But he is concerned not only about making them better, but also making them affordable,
I actually am concerned about the insurance reimbursements because people aren’t going to be able to afford these devices if they’re not covered by insurance. No one’s going to be able to layout $10,000 and all the consumables and the sensors unless it’s covered and you’re getting reimbursed for it, but I have patients who are on these devices that were not in the study. It’s about 6 weeks now. 4-6 weeks now that I’m starting to get regular clinic patients get on this device.
While some insurance companies have started paying for them, there’s still a major issue as to when Medicare will get on board as well, and that’s going to make a huge difference in the adoption of the systems.
Right now, the Medtronic device is approved for Type I diabetics aged 14 and up. The company’s first goal is to get that age down to seven. After that is the battle to get it approved for the many Type II diabetics who are on full insulin replacement. But that, according to both Medtronic and the clinicians we spoke with, could still take years.
Gary Kaye is the creator of Tech50+ (www.tech50plus.com), the leading website covering technology from the Baby Boomer perspective. Kaye has been covering high tech for more than 30 years with outlets including NBC, ABC, CNN and Fox Business. He is a regular contributor to AARP and other websites on issues regarding the nexus of technology, seniors and baby boomers.
