Just a few days ago I noted the future of implants really is going to be medical sensors that use the same passive power and data transmission methods as passive RFID, and now I hear about these guys doing exactly that for glucose measurement. I was diagnosed with type 1 diabetes recently- I am waiting for my implant to arrive for the motorbike project and as such have spent most of my time in hospital researching this and how to implement it into monitoring glucose levels.
I’ve been wearing the new Dexcom G4 Platinum continuous glucose monitor (CGM) for almost two months now. Now, this lessened pain would be enough to make me switch from the Minimed even if the Dexcom were less reliable.
When I originally chose the Medtronic Minimed, one of the biggest deciding factors was that I was already wearing a pump, and didn’t want to carry around an extra receiver (which, at the time, was the fugly, egg-shaped Dexcom one).
Despite giving the initial impression of an Apple-like device, the Dexcom G4 Platinum receiver proves more like a cheap knock-off when it comes to the things that make Apple device feel really well designed. Style aside, one thing I had gotten used to with the Minimed was that I could easily scroll back in time and see previous glucose reads.
I should also mention that, despite being more consistently reliable than the Minimed CGM, the Dexcom G4 is not perfect, and is not a replacement for a blood glucose monitor. Because it is a limitation of measuring interstitial glucose, I forgive the Dexcom for its periodic diversions from blood glucose. One of the things I was promised about the Dexcom was that their software and analysis tools were really helpful. The greatest irony, of course, is that, as I mentioned above, the Dexcom G4 is clearly designed to look like an Apple product — and yet the software doesn’t work on the very products that Dexcom is imitating! I do have a question though… what do you use over the sensor (as I see in the picture above)?
Leighann – I never thought about how the increased range could allow a parent to keep it with them overnight. While I thought the transmitter size was NOT going to be an issue, I have found it to be a rather big one since I’ve had a couple rip off due to it catching on things. With regards to Mac compatibility, everyone has to remember that they are dealing with the FDA, so that adds a layer of complexity only god knows how thick it is. I met with folks from Dexcom last year and re-emphasized the issue with the vertical scale. Great review and I have the same thoughts as you with comparing the Dexcom to Medtronic With my daughter.
This comparison should be removed from the Internet ASAP; it is completely antiquated and comes off as an employee of dexcom.
In short not speaking against Dexcom just saying this article is antiquated as a new CGM, the S light from Minimed is out, has painless insertion -Yes it is painless and performs extremely well. Again, no mention of Dexcom CGM OUTPERFORMING the Minimed CGM sensor as it pertains to better control of long term blood sugars is irresponsible by the original author! The Diabetes Media Foundation is a 501(c)(3) tax-exempt nonprofit media organization devoted to informing, educating, and generating community around living a healthy life with diabetes. This dual reduction in A1c and hypoglycemia demonstrates the power of automating insulin delivery – shaving off lows AND highs, particularly overnight. Medtronic has submitted this system to the FDA as planned, with a US launch previously expected by April 2017.
This represents the first pivotal trial of a fully integrated commercial product to automate insulin delivery, and it shows what a difference first-generation hybrid closed loop systems can make, even in patients doing pretty well already. Unlike many academic systems that run the closed-loop control algorithm on a smartphone, the 670G algorithm is fully integrated within the pump itself. In addition to these study results, Medtronic announced some important diabetes data updates at ADA, including information on its next-gen CareLink Pro reports for providers (to help optimize pump settings), its partnerships with Glooko and IBM Watson (both launching this summer), and a new food app with Nutrino (beta app available).
By the end of the study, 55% of trial participants had an A1c under 7%, up from 31% at the study’s start. Q: What impact did the hybrid closed loop have on “time-in-range,” hypoglycemia, and hyperglycemia? While the time-in-range increase may seem minor, considering the meaningful hypoglycemia reduction and the high baseline time-in-range, these results are still notable.
A: 124 participants with type 1 diabetes (94 adults, 30 adolescents) were enrolled in the study.
Participants began with a two-week “open-loop” phase during which they wore the MiniMed 670G pump + Enlite 3 CGM, but without any insulin automation. At the ADA Scientific Sessions in New Orleans, Abbott shared results of the IMPACT study, a randomized six-month trial comparing the FreeStyle Libre “flash glucose monitor” to fingersticks in people with type 1 diabetes (see more on how the Libre works here). FreeStyle Libre essentially replaced fingerstick testing, suggesting a high level of confidence in the accuracy of the “no calibration” sensor. The nighttime results help counter the argument that Libre’s lack of alarms poses a danger. IMPACT highlights the daunting amount of hypoglycemia those on insulin therapy (type 1 in this case) are experiencing every day. These results also underscore the limitations of using A1c as the sole measure of good glucose control. The IMPACT study follows the REPLACE study, which studied the Libre’s impact on A1c in people with type 2 diabetes and high baseline A1cs. FreeStyle Libre (real-time version for patients) is currently available in several European countries and Australia, but it is not clear when it will launch in the US. Disappointingly, the study missed its primary goal, demonstrating similar 0.3% A1c improvements in both groups. Nighttime hypoglycemia similarly improved with FreeStyle Libre, which is important, given the absence of alarms on the device. These results serve as a reminder of how much hypoglycemia impacts type 2 diabetes, and more important, how challenging it is for diabetes technology to improve A1c AND reduce hypoglycemia at the same time – cutting down on lows is a good thing, but it unfortunately raises average glucose (and thus A1c).
It’s worth noting that the study design did not tell providers and patients what to do with the comprehensive glucose data from FreeStyle Libre (a real-time glucose value taken every minute, 24 hours per day).
It will be interesting to compare these results to the type 1 study, IMPACT, which will be presented at a conference this June. It’s not clear when FreeStyle Libre (real-time version for consumers) will launch in the US. All things considered, we salute Abbott for conducting this ambitious, long-term outcomes study of FreeStyle Libre. For now, LibreLink is only available for Android phones with built-in NFC (most models have this, including the popular Samsung line). Colorful design – LibreLink maintains the same excellent report features from the FreeStyle Libre reader, but in a more visual, colorful design. Improved data sharing – data is saved directly into the app and allows users to email reports directly from the phone.
The FreeStyle Libre has several key differences from the Dexcom G5 Mobile System and continuous glucose monitoring in general (see our guide: How is FreeStyle Libre Different from Continuous Glucose Monitoring?).
LibreLink app does not have to be open to obtain a glucose reading – if the phone is unlocked, the reading will come up on screen automatically after the sensor is scanned by the smartphone. Not required to purchase the FreeStyle Libre reader device (we view this as a meaningful advantage). There is no updated timing on an FDA submission of the real-time, consumer version of FreeStyle Libre. FreeStyle Libre Pro is a bit different from the patient version of FreeStyle Libre discussed above.
We’re hopeful that a future FDA submission of FreeStyle Libre includes the LibreLink app – many patients will appreciate the convenience and user experience advantages!
Unlike the FreeStyle Libre system currently available in Europe, the Pro version does not give patients a reader device to look at glucose values in real time. Professional glucose monitoring systems like FreeStyle Libre Pro are generally reimbursed well by insurance, including Medicare.
Of course, we are huge fans of arming patients with real-time knowledge about their glucose, and we’re very excited about a real-time unblinded, commercial version of FreeStyle Libre coming to the US. Abbott recently announced the launch of the FreeStyle Precision Neo, its newest blood glucose meter.
Abbott’s goal with the Neo is to offer very high quality strips to those purchasing them without insurance.
Bottom line: The Neo itself is simple and basic feature-wise, though since many patients have financial barriers, it could be a great way to access high-quality blood glucose testing at an affordable price. Trial name: Glucose Variability Pilot Study for the Abbott Sensor Based Glucose Monitoring System-Professional. The Pro sensor can track glucose data over a two-week period whereas the Libre sensor only tracks glucose data history over an eight-hour period (this is why the consumer version recommends scanning with the touchscreen reader every eight hours). Volunteers in the study will wear two Libre Pro sensors (one on each upper arm) for two weeks, during which time they will go about their normal daily activities and follow their typical diabetes management plan. Doctors may not want to overwhelm patients with continuous data, especially those who are only used to seeing a few readings per day from their traditional blood glucose meter. Trial Location: Seven locations across the US, including three in CA and one in MI, MO, NC, and TX.
A full list of the inclusion and exclusion criteria can be found at the clinicaltrials.gov site.
At this year’s ATTD Conference in Paris, a good deal of excitement centered on Abbott’s FreeStyle Libre glucose monitoring system, which launched in Europe last October. New user experience data from a 72-person study was presented at ATTD, emphasizing the Libre’s convenience and comfort. 88% agreed that applying the sensor was less painful than a routine fingerstick (more to the point, we’d add that insertion is only required once every 14 days).

Before that, I used the Minimed CGM with my Minimed pump for about two and a half years, so I come to the Dexcom not as a new user or a familiar user, but as an experienced user with allegiance to another manufacturer. The insertion device requires a slow, gradual insert, which is sort of strange, but arguably preferable to the single-button-push approach. I have been using the Dexcom sensor for almost two months; my first sensor, on my back, lasted about 9 days. Switching over to the Dexcom G4 Platinum, I worried about the extra burden of yet another device, but two months in, it hasn’t been that bad.
The fake scroll wheel (designed to look like the patented Apple scroll wheel, I presume) is actually made up of five buttons. I don’t know because when I went to the website to sign up and log in to upload my data, I saw instead a link to download the Dexcom software. However, I would be willing to put money on the bet that the percentage of Mac users among CGM users is much higher, since you’re selecting for a higher-income, more-comfortable-with-new-technology population. It is incomprehensible to me that after so much time, money, and effort is put into building a device, Dexcom would embarrass themselves so spectacularly with the software. I actually used Bootcamp to install Windows on my old Mac this past week in anticipation of our endo appointment and all it did was confirm to me how clunky Windows is. The Medtronic harpoon device scared my daughter to the point that I could only put on a sensor while she was sleeping…and thoroughly numbed.
I’m a software developer, tech-geek extraordinaire and I’m soooo jealous of your computer setup! I use Linux at work and (unfortunately) I have a Windows computer at home, but am hoping to buy a MacBook within the next year.
Very much love how you look at the irony of Apple-imitation, yet it doesn’t work on Macs. Then you get into iterations of software for both Windows AND Mac and now you have an even bigger headache. I’ve been using the Medtronic CGM for two years, and every so often I think about switching. I told them that once my blood sugar was over 300ish I didn’t really need the graph, just the value and arrows.
From looking at the internals of their installed software it’s clear they used a lot of Windows functionality to implement it. My biggest thing with the older Dexcom was it was big and she was already wearing a pumbrand would leave the Dexcom transmitter in her room or somewhere, so we had no data.
Take note of the images below, which show the combined daily glucose profiles in adults (B) and adolescents (C) for the open loop run-in (gray) and hybrid closed-loop with the MiniMed 670G (pink). As we previously reported, of the 124 patients in the trial, a striking 80% have opted to continue using the device through the FDA’s continued access program – this demonstrates encouraging participant enthusiasm for the system, plus FDA comfort with real-world use of the device. Its average error in this pivotal trial relative to lab measurement was 10.3%, needing a minimum of two fingerstick calibrations per day. Patients were already doing well at study start, though the 670G brought A1c down a further 0.5% and cut hypoglycemia by 44% – it’s rare to see both improve with a diabetes drug or device, and the results were consistent in adolescents and adults. Medtronic chose this design deliberately, as it wanted to complete the study as fast as possible and submit the device to the FDA. A patient only needs to wear the Enlite 3 CGM sensor and the MiniMed 670G pump – no need to carry a separate CGM receiver or phone. Inversely, that means that 45% of participants ended the six-month study with A1cs still above 7%. Moreover, the hybrid closed loop system significantly reduced severe highs and lows, tightening the range of glucose values throughout the day (see above).
It is possible participants ate differently on the hybrid closed loop, which could also explain the mild weight gain seen with the system (about three pounds in adults and two pounds in adolescents).
We love seeing this change and think providers and patients will appreciate the greater flexibility in viewing data. Nutrino imports the CGM and insulin data seamlessly from MiniMed Connect (from a Medtronic pump) and allows patients to take meal pictures, scan bar codes, carb count, and more. The software will identify the optimal insulin:carb ratio, the insulin sensitivity factor, and necessary basal rate changes.
The trial recruited 241 participants with an average starting A1c of 6.7% (considered “very good control”) and lots of hypoglycemia at the start of the study (~200 minutes per day!). There is now solid evidence from two studies that Libre can help patients and providers identify some nighttime hypoglycemia and make changes accordingly.
Both groups saw a 0.15% increase in A1c in this study, though the quality of A1c improved markedly in the FreeStyle Libre group with significant reductions in hypoglycemia and more time-in-range.
Unfortunately, the Libre did not significantly reduce A1c in that study, though it did reduce hypoglycemia and improve quality of life as well (read more here). We learned at ADA that Abbott has not yet submitted it to the FDA, meaning it likely won’t be out until 2017 or later. We assume the retrospective glucose data helped patients and providers identify nocturnal hypoglycemia. Two different measurements of quality of life (the Diabetes-Treatment-Satisfaction Questionnaire and the Diabetes Quality of Life survey) showed an increased overall satisfaction for FreeStyle Libre vs.
That was a deliberate decision to ensure a real-world trial, though it may have impacted the results.
That trial’s goal is to show reductions in hypoglycemia in patients with an A1c of less than 7.5%, which seems like a given after REPLACE. Abbott’s CEO recently said that it might be available by the end of 2016, though this statement was ambiguous, and we’re not sure if FreeStyle Libre (consumer) is even under FDA review.
The ultimate mark of any technology is whether people will buy it, and FreeStyle Libre has no issues there – demand has been off the charts since it launched in Europe in fall 2014.
We’ve heard that many children in Europe are already using this device “off-label,” though this official approval is certainly great news for helping more kids get access to this new technology. This important advance eliminates the requirement for the separate touchscreen reader and further builds on the “Libre” name – freedom from fingersticks, and now, freedom from an extra device!
Once it is installed on an Android phone, a user can start a 14-day sensor and obtain real-time glucose information by briefly holding the back of the phone near the sensor, just as one would do with the reader. This eliminates the requirement to plug in the reader to a computer (though with a USB cable, that's pretty easy too!). However, since both devices now offer smartphone apps that completely replace a separate handheld device, we think it’s useful to compare them. The Pro version is blinded (no reader device or app) and allows physicians to get continuous glucose data from patients over a two-week period. Abbott’s quarterly update call revealed that the company has submitted the professional version of FreeStyle Libre for regulatory approval in the United States. Libre Pro allows physicians to get continuous glucose data from patients over a two-week period. A blinded sensor like FreeStyle Libre Pro makes it more likely patients will stick to their normal routine – allowing providers to get a more realistic view of a patient’s day to day management. For now, it’s not clear when that might happen, though we assume it will come after Libre Pro launches. The study’s main objective is simply to ensure that the Libre Pro is able to gather accurate glucose data over a full two-week period. As in the trial, patients in the real-world setting would not see the glucose data until after the two weeks is over. The 14-day sensor and touchscreen reader is intended to replace glucose meters, but provide CGM-like information (real-time reading, trend arrow, history). Biorasis, the company that is developing this technology, has put together a video that runs through the implantation and utilization process.
The worst kind of user for a company, in many ways — so, while others have done a great job reviewing in detail the new Dexcom G4 Platinum, I will focus on my experience with the new device as compared to what I have come to expect based on the Medtronic Minimed system. Further, because the insertion device and sensor are so reasonable, I am able to wear the CGM places other than my abdomen, which I was terrified to even try with the Minimed.
After two years with the Minimed, I had gotten pretty used to its quirks, and could often tell when it was likely to reflect my blood glucose well, and when it was likely to be off. The receiver was designed to look Apple-y, and it’s fun to show off the color plot of my blood glucose values to all my (admittedly geeky) friends. These buttons are sort of hard to press correctly because they are all connected and give no tactile feedback when pressed. The Dexcom, however, obscures those values– I can see the most recent read, the plot of dots, and an arrow, but not previous reads. This, however, is a problem inherent in the way CGMs are currently built, and may require new technology that relies on alternate sources of glucose to fix.
That was exciting to me — I am an engineer and analyst by trade, and so I love graphs and numbers and statistics. Between work and home, I have 32 GB of RAM, 5 TB of space (500 GB solid state!), and sixteen processors. Even Minimed had (after some time) a multi-platform web app– it was a crappy web app with Java applets, but it was at least a web app. Further, if you know you only have the resources to maintain one type of software, there is no reason not to build a web application in this day and age.
Maybe this is part of the reason why they bought Sweet Spot – so they could put it all online and perhaps make it both more easily Mac and PC compatible. I also suggested that the value above the graph should remain on the right, like the Dexcom 7+.
There are some libraries available to emulate parts of this functionality on other platforms, I really hope they do this soon.

The G4 is much better with larger range but I do like having the Medtronic integrated with the pump.
The 670G tightened the range of glucose values throughout the entire day (particularly in adolescents) and was very effective overnight in both populations. This is slightly worse than Dexcom’s G5 at ~9% with two calibrations per day, but much better than the previous Enlite at ~14%.
This study enrolled current pump users, some of whom were already on a CGM; it’s not clear how people on injections would like this device. The solid (670G) and dashed lines (open loop) indicate the average glucose at that time point.
The range of glucose values was much narrower overall at all time of day, particularly after breakfast. Glooko will also launch a re-designed patient app that can perform pattern recognition, among other features.
Meanwhile, the control group was still spending three hours per day in hypoglycemia with a “good” A1c 6.9%. By contrast, FreeStyle Libre Pro (blinded, retrospective, placed in a healthcare provider’s office) has been under FDA review since mid-2015, with approval hoped for the middle of this year (yes, any minute!) in the US. The six-month trial compared use of the “flash glucose monitoring” system FreeStyle Libre (see more on how the Libre works here) to standard fingersticks in type 2 patients on basal-bolus insulin therapy. Compared to the study start, those translated to 55% and 68% reductions, respectively, in FreeStyle Libre users. For instance, the FreeStyle Libre download software very clearly points out hypoglycemia with a red traffic light.
The ultimate hope is to use the results from these two studies to support European reimbursement of FreeStyle Libre. By contrast, FreeStyle Libre Pro has been under FDA review (blinded, retrospective) since mid-2015, and this should launch sometime this year. The app is available on the Google Play store in Sweden, and Abbott told us that more European launches are planned for 2016, including France, Germany, Netherlands, Italy, Spain, and the UK.
The app then immediately shows the current glucose reading, trend arrow, and eight-hour history.
After applying the Libre Pro sensor in the doctor’s office, it is worn for two weeks, and the sensor automatically records glucose values every 15 minutes. It consists of a small sensor (a bit larger than a US quarter dollar coin) worn on the arm. The good news is that an FDA approval of FreeStyle Libre Pro might make the approval path for FreeStyle Libre easier. The Neo meter and test strips are already available online at major US retailers like Walmart and CVS. The Neo meter retails for $22-27, and the test strips are available without a prescription (over-the-counter) at $14-17 for 25 strips. The Neo’s test strips are packaged individually in flat foil, aimed at greater convenience for testing.
The trial will measure the participants’ glucose variability, as measured by the Libre Pro sensor, but again the data is not intended to alter volunteers’ daily activities or treatment plan.
In line with our positive experience wearing the system, the Libre has been a major hit in Europe, and Abbott’s biggest challenge is actually meeting demand. Iain Cranston (Portsmouth Hospitals NHS Trust, England) said, “Half my patients have not done a fingerstick in two months. Even after more than two years with the Minimed system, every time I inserted a new sensor, I would stand there for a few minutes, mentally convincing myself that it wouldn’t be that bad, and that the pain was worth it, before finally pressing the button to send the giant need into my abdomen. Thus far, I have worn the Dexcom on my lower back (worked all right, but sub-optimally; it was prone to getting knocked and jostled off) and my arm (works capitally). I am still learning these things for the Dexcom, but the default behavior of the Dexcom seems much more sensitive to changes in my blood glucose. Sometimes I press, wait for a few seconds for the screen to come on, and then realize I apparently didn’t press hard enough or in the right place. The arrows are helpful, but I want a more fine-grained evaluation of my slope, and I can’t get that with the Dexcom. I have access to three compute clusters, and I could spin up an infinity of Amazon EC2 instances if I needed them. In a few months, the new Minimed Enlite may be a competitor, but the Dexcom is pretty darn good today.
I also am frustrated that from what I’ve seen from their upcoming Sweet Spot software (the company they acquired last year to create a web-based data app), they still are not taking user concerns into account.
Yes, the insertion of the Minimed sensor was short of torture; but the temporary discomfort Is well worth the main point of stabilizing long term blood sugars. Abbott’s FreeStyle Libre has an ~11% error, but it does not require any fingerstick calibrations. It’s a “hybrid closed loop” because a user still needs to bolus for meals and notify the system of exercise. Adults saw a slightly higher average glucose on the 670G during the day, but a narrower range overall. Unlike the adults, the adolescents saw a lower average glucose on the 670G at many times of day. Hybrid closed loop systems won’t be perfect, since they only modulate basal insulin and still require accurate carb counting and meal boluses. During this phase, participants used the system unsupervised, meaning these three months reflected “real-world” experience with the hybrid closed loop system. Will the FDA and insurance companies appreciate the “higher quality” A1c outcomes that next-gen devices and drugs might bring?
Were patients on FreeStyle Libre and their providers surprised to find lots of unrecognized hypoglycemia, prompting them to reduce insulin accordingly?
As a reminder, patients currently pay (out of pocket) 59 euros (about $66) for each 14-day FreeStyle Libre sensor, and 59 euros for the touchscreen reader. After applying Libre Pro in the doctor’s office, it is worn for two weeks, and the sensor automatically records glucose values every 15 minutes. While there weren’t many new tech updates on the Libre at ATTD, we did learn more about the system’s accuracy and how patients and health care providers like it. This ability to move the sensor around opens up my abdomen, which was getting bruised and scarred to the point of not being usable.
Beyond style, though, this means that the device is small and light, and I can carry it in my pocket. So I’ve been REALLY TEMPTED to switch up to the G4 and even go with another someday-Dex-compatible pump. We also hope to hear more on usability of the system, as some have told us it does require a learning curve. If a patient misses a mealtime bolus, for instance, blood sugars will likely stay elevated for some period of time before the higher basal rate brings it back down. A one-week hotel study occurred in the middle of the 670G period, allowing a comparison between the Enlite 3 and a laboratory reference.
This is of particular concern in older patients, the very same population that did not see an A1c benefit in this study.
Or at the very least allow me to see the actual past values– but to give me a difficult-to-interpret graph and no numbers?
I was also on a call with their CEO where Bernard (along with me and some other people) raised these same concerns. The sensor is worn for 6 days; I’m not going to comptmise my health by wearing it any longer! Still, the automated basal insulin delivery takes care of insulin dosing in the background, which is particularly valuable at night (~80%+ time-in-range), and can help mitigate many highs and lows during the day. In that sense, the results tell us as much about FreeStyle Libre’s ability to reduce hypoglycemia as they do about the real-world dangers of insulin therapy, especially in “well controlled” patients; three hours per day in hypoglycemia is downright dangerous. Of course, it is also much easier to fix hypoglycemia (reduce insulin) than to safely bring average glucose down (“Is it correction or food bolus? The FreeStyle Libre sensor can only link with one device, so people must decide whether they want to use the touchscreen reader or the LibreLink app over the 14 days of wear – unfortunately, you cannot tradeoff between the two devices.
Abbott has done a really good job of making the glucose data download easy to interpret, meaning healthcare providers and patients can quickly grasp what is going well and what may need improvement. However, the anecdotal evidence at ATTD suggests that many patients are relying completely on the system. I also wonder if there is a reason that the one button press to get the screen going doesn’t always work.
An accuracy trial for Libre is now underway in the US, which could help lead to future US approval.
Avoiding lows on insulin therapy is truly difficult as A1c gets below 7%, and we’re not sure that delicate balance is appreciated enough. While she uses the difficulty of usb cover as the reason why it is often left open, while it isn’t easy, I question her memory more.

Target blood sugar levels for type 1 diabetics eat
8.6 blood sugar level reading test


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