The little white disc glucose sensor worn on the arm known as the Abbott FreeStyle Libre came to the continuous glucose monitoring (CGM) market years ago with a handheld scanner, requiring users to manually swipe the receiver to get readings. But now, this popular device is doing away with that need, making it a more automated and easy-to-use solution for people with diabetes.

In September, Abbott Diabetes received international approval of its tiny new FreeStyle Libre 3 version outside the United States, putting it on track to offer functionality on par with competing CGM devices from Dexcom, Medtronic, and even the implantable Eversense.

Abbott plans to bring Libre 3 to the U.S., and in the meantime, they’ve launched a new athlete-focused biosensor for those without diabetes.

There’s a lot happening with the Libre, and here’s a deep-dive into that evolving story since the product first debuted globally in 2014:

Abbott Libre is known as Flash Glucose Monitoring (FGM) technology because it has offered a “flash” of a glucose reading whenever you scan the sensor with the handheld receiver or smartphone app.

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Abbott Freestyle Libre, via Getty Images

Since hitting the U.S. market in 2017, Abbott has continued to gradually roll out modifications and new features. Finally, in 2020, the Libre has reached a point where it can be considered a “fully-functional CGM.”

The biggest change in the Libre 3 version that obtained CE Mark approval in late September is doing away with the need to scan the sensor.

The round, fully-disposable sensor is now much thinner and smaller in size, too: the thickness of two pennies (rather than two stacked quarters in earlier versions). Per Abbott, that is a more than 70% size reduction that uses 41% less plastic.

It generates a new real-time glucose reading every minute, displaying that result on the compatible mobile app on iPhone or Android. This continuous stream of data allows optional real-time alerts for high and low blood sugars, along with real-time glucose results. This is a big leap forward compared to the Libre 2 that required a confirmation scan before getting the numeric reading.

As with the earlier models, the Libre 3 still has a one-hour warmup period before it starts offering data.

Abbott also points out that pricing doesn’t change with the latest model, and will remain consistent with the earlier versions.

The evolving pipeline of Libre technology, with most models having the same name, can be a bit confusing.

Libre 2 with optional alerts

Just approved by the FDA in June 2020 but available overseas a couple of years before that, the Libre 2 was the first model to introduce optional glucose alerts for highs and lows. It uses Bluetooth to determine the glucose range — programmable from 60 to 100 mg/dL in order to trigger a Low alert and 120 to 400 mg/dL for a High alert. While the notifications came without a need to scan the sensor, you still needed to scan the sensor before getting an actual result.

For many people, that continued need to scan before getting a result meant the Libre 2 still didn’t offer the same kind of protection for high and low glucose levels as competing CGM tech offered — particularly overnight, when hypoglycemia can be even more dangerous as people are sleeping and not actively monitoring or experiencing symptoms.

The first two iterations of the FreeStyle Libre — named the 14-day and 10-day, respectively — were pretty much the same base technology as the Libre 2, minus optional alerts. Both also included the handheld scanner needed to get results, though the 14-day unit eventually could be scanned with a smartphone app instead of the handheld receiver.

The mobile health tools used with this FreeStyle technology also have a variety of names, some differing based on geographies outside the U.S.

LibreLink: The main mobile app used to scan and view your readings. There’s a reports section offering the Ambulatory Glucose Profile (AGP), a standardized single-page report with glucose and insulin info in a colorful, easy-to-read format. There’s also a share function that allows users to easily send these reports via text, email, etc. to anyone, similar to the photo-sharing button used to send pictures to contacts on your phone.

Libre LinkUp: A separate mobile app used for others to view Libre data. The user scans their own sensor with the LibreLink app or separate handheld device, and then up to 20 people can use the Libre LinkUp app to see that data once it’s beamed to the cloud.

LibreView: A digital web-based platform for healthcare professionals. American users have had access to this online platform for viewing their Libre-generated data and sharing it with care providers for some time now.

Libre Sense: A biosensor for sports

There’s been a lot of talk of creating CGM systems aimed at non-diabetics, especially athletes. More companies are moving in this direction and turning to the Libre technology developed by Abbott as a basis for their programs.

One of the most visible moves in that direction is with the Libre Sense from Abbott, launched worldwide in September 2020.

This so-called “Glucose Sport Biosensor” has the same form-factor of the early Libre sensors (thickness of two stacked quarters), it’s aimed at athletes and fitness-focused folk who may not necessarily have diabetes but want to monitor glucose levels in the context of their health and activity levels.

For ages 16 and older, it’s not a prescription product and can be purchased over-the-counter. The sensor lasts up to 14 days just like the other Libre sensors, and wearers automatically receive streaming glucose data via Bluetooth every minute and viewed on a compatible mobile app.

Abbott’s Medical Affairs Director Jim McCarter explained the use of glucose sensors in sports to DiabetesMine: “When someone is early in a workout — and they’re exercising at high intensity — they’ll actually see a rise in glucose. That’s the body responding to the stress of the event. Later in exercise — and especially in endurance exercise — as glycogen stores are depleted, glucose will begin to lower. And that’s especially important in long-distance endurance events.”

A Swedish study of elite swimmers found that understanding real-time glucose levels can help athletes know what to consume and when, which helps improve muscle recovery and athletic performance. Meanwhile, an American College of Sports Medicine study cited by Abbott notes that athletes who understand the impact of what they eat and drink will have a better chance of improving their performance.

Supersapiens mobile app

The Libre Sense is distributed by and works with a specific compatible third-party app, created by new sports tech startup Supersapiens, which was founded by professional cyclist and fellow type 1 Phil Southerland.

“I think {the Libre Sense] is important, as it will help to expand the amazing technology into the world without diabetes. When athletes of the world begin to realize just how difficult it is to optimize glucose with a ‘functional pancreas,'” Southerland says. “My thought and hope are that we can create a deeper connection with the diabetes community than ever before.”

Using analytics to examine the glucose data from the Libre Sense, the Supersapiens app is aimed at helping athletes improve their fueling strategies and sustain peak performances in sports. It offers data analysis with personalized insights and recommendations on athletic events, as well as sleep and food patterns that tie into an athlete’s energy levels. There’s also an in-app education hub for community learning from other athletes, scientists and coaches.

Libre Sense is offered on a subscription model priced at €130 per month, including the sensors as well as the app and analytics that go along with it. Southerland expects the first batch of customers in the European Union to start getting products by year’s end, and 2021 will be a big year to build on that.

Southerland says his small company, based in Atlanta, has 35 employees and works with world-renowned athletes as early adopters.

“We have some big plans to change the world, and are extremely grateful to all of the adopters of CGM in the diabetes world who all played a role in pushing the technology to the point where we can finally share our superpower with the sports world,” he says.

As noted earlier, Supersapiens isn’t the only startup focused on a business model using the Libre CGM tech. Others include Levels Health, Nutrisense and so far, and more will likely follow in developing platforms for those without diabetes.

Abbott has signed multiple development agreements with partners allowing its Libre monitor to work with future closed loop, or Automated Insulin Delivery (AID) systems.

In June 2020, the Food and Drug Administration granted the Libre 2 a special iCGM designation, meaning it has the potential to work with other pieces of diabetes technology, although unlike the similar designation granted to the Dexcom G6, Libre 2 is not supposed to be used with insulin delivery systems.

Most believe this is because the Libre 2 doesn’t offer real-time continuous data as the G6 does, but requires follow-up scanning for Highs or Lows to get an actual reading for treatment. Most likely, the new Libre 3 will receive the full iCGM designation soon after its launch in the U.S.

Once that door opens, we’ll likely see the Libre 3 paired with technology such as Tandem’s t:slim X2 insulin pump that has also has interoperability clearance, as well as future automated systems from developers like Bigfoot Biomedical.

With all this Libre tech in the pipeline, it’ll be fascinating to see what Abbott Diabetes Care brings next for improving life with diabetes.