FDA clears Dexcom G6 with factory calibration, creates lower-risk 510(k) path for “integrated CGM” (iCGM) to speed innovation and interoperability – March 27, 2018

Executive Highlights

  • The FDA and Dexcom just announced clearance for the factory-calibrated G6 CGM system under a new de novo pathway for “integrated CGM” (iCGM). This new pathway could be game-changing, as G6 and future iCGM systems are down-regulated from a high-risk Class III (PMA) to a lower-risk class II devices (510(k) clearance) – enabling faster iterative innovation and less regulatory burden! G6 is also cleared with interoperability in mind – it’s part of the indication – streamlining the regulatory process for future devices/software that connect to G6 (e.g., pumps, wearables, mobile apps), allowing Dexcom to move faster, and minimizing submissions for iteration.
  • A US launch of G6 is expected late in 2Q18, with an international launch planned for 2H18 following CE Mark. Today’s homerun FDA news – especially factory calibration and the unexpected down-classification to 510(k) – is coming three months earlier than Dexcom’s “goal” for a mid-2018 approval. Wow – this regulatory team really knows how to work with the FDA to push the field forward!
  • The no-fingersticks G6 is cleared for 10-day wear with a mandatory shutoff. It maintains a two-hour warmup and G5’s non-adjunctive (insulin dosing) labeling. G6 is approved down to age 2+years, adds acetaminophen blocking, and finally brings the one-touch applicator and 28% lower profile transmitter to market – the latter look terrific in the media kit video. Dexcom’s investor call and G6 simulator app confirmed that users can enter an optional fingerstick (e.g., in the occasional case of an errant sensor), but this is buried in the app’s settings and discouraged. G6 also comes with slightly redesigned apps (Apple, Android), along with the receiver.
  • Importantly, FDA has also established criteria (special controls) that outline requirements for iCGM systems (510(k) pathway), including a performance standard, a requirement for acceptable sensor lot release practices, and controlling for secure and reliable data transmission. These are posted here as part of the FDA’s letter to Dexcom, and you can read our complete analysis here. For now, this is clearly a competitive advantage for Dexcom, particularly because we confirmed with FDA’s Dr. Courtney Lias that FreeStyle Libre will not meet the controls – continuous communication is part of them. We’ll be back with more analysis on these, but the accuracy criteria are definitely tight and we’re not sure if anyone other system can meet them right now. CEO Kevin Sayer similarly emphasized on the investor call that the bar is “rigorous” to achieve the iCGM standard and get into the 510(k) pathway. The existing PMA process will remain in place for CGM.
  • There are no details on pricing, but we’d guess the 10-day wear gives Dexcom some more flexibility here. The mandatory shutoff is a first for Dexcom and something it will need to manage with users; on the plus side, that will significantly augment Dexcom’s topline revenue. A receiver is still required with G6, with FDA discussions to follow about making it optional. Expanding to 14-day wear is in the pipeline, but not a 2018 event. Verily gen one timing will be shared on the 1Q18 call.
  • Overall, G6 is a tremendous feature upgrade on G5, especially for competing with FreeStyle Libre and driving faster innovation ahead. We expect big momentum for Dexcom – and the category – once G6 launches. See below for a SWOT analysis and side-by-side product comparison with Libre and Guardian Connect.

In far-earlier-than-expected news, the FDA just announced marketing authorization (clearance) for Dexcom’s factory calibrated G6 sensor! A launch of the 10-day wear, non-adjunctive, no-fingerstick, real-time, interoperable-focused CGM is expected in the US late in 2Q18 (before ADA), with an international launch planned for 2H18 following CE Mark. More will be shared on the 1Q18 call.

G6 will have a mandatory 10-day shutoff (like FreeStyle Libre), brings the long-awaited one-touch applicator and 28% lower profile transmitter to market, and includes Apple iOS and Android apps and a touchscreen receiver (must be purchased, for now). Dexcom hosted a short 28-minute conference call ~16 hours following the news, which can be listened to here.  

In major, industry-changing news, FDA granted marketing authorization for the G6 sensor under a new regulation it is establishing called “integrated continuous glucose sensor,” or “iCGM” for short. Under this “unprecedented” de novo pathway, G6 and future systems like it are actually down-regulated from a high-risk Class III (PMA) to a lower-risk class II device – in other words, Dexcom CGM will now be regulated under the 510(k) process, like BGMs and pumps! Future iCGMs will be able to send 510(k)s to the FDA and claim the G6 as a predicate device.

As an iCGM, G6 is also cleared with interoperability in mind, streamlining the regulatory process for Dexcom CGM innovation, future systems that connect to G6 (e.g., pumps, wearables, apps, dosing algorithms), and minimizing FDA submissions for design changes. The FDA press release headline is very notable: “FDA authorizes first fully interoperable continuous glucose monitoring system, streamlines review pathway for similar devices.” G6 accomplished this via a new indication for use that includes the following line: “The G6 can communicate wirelessly to and from other interoperable devices.” This is the first major step in FDA’s vision for plug-and-play, component systems that minimize regulatory burden and allow users more choice. The investor call also emphasized this allows Dexcom to move faster on innovation with partners. AID systems will remain Class III devices, but G6 will be a class II component of these systems. The existing class III PMA path will remain. Overall, this will massively help Dexcom’s pump partners, who can get clearance to talk to an iCGM (e.g., G6), but won’t need a whole new PMA submission for small CGM design changes. Win!

Notably, this better-than-expected, homerun FDA news is coming three months earlier than Dexcom’s 4Q17 “goal” for mid-2018 – wow! This is easily one of the biggest regulatory wins in Dexcom’s history, and it comes ~6 months following G6’s 3Q17 submission. (It’s also 12 years to the day that Dexcom first CGM system was approved!) This is a notably fast review for any standalone CGM, given a ~one-year review for FreeStyle Libre (real-time) and a two-year review for Guardian Connect.

The down-classification to 510(k) is a major first in CGM and could blow open the doors to even faster iterative innovation for Dexcom, as well as other systems that can meet the new standards to be an iCGM (see below). Huge kudos go to the FDA for taking this enormous step forward and propelling interoperability, a need that is only growing as AID and decision support move ahead. With the factory calibration win for G6 and down classification to 510(k), Dexcom’s regulatory team has again pushed the industry envelope on CGM labeling. G6 will still require a prescription.

Along with this authorization, the FDA has established criteria (special controls) that outline requirements for iCGM devices’ accuracy/reliability and the studies/data required to demonstrate acceptable performance and be cleared under a 510(k) path. These controls are posted here as part of the FDA letter to Dexcom, and you can read our complete analysis here of the minimum performance standards; the requirement for acceptable sensor lot release practices; and an adequate way of controlling for secure and reliable data transmission to the other device(s). The bar has been set very high on accuracy standards and we don’t believe all other companies’ CGM systems (as approved now) will automatically meet them. For now, this is definitely a competitive advantage for Dexcom, particularly because FDA’s Dr. Courtney Lias told us that FreeStyle Libre (as it stands) will not meet the controls – continuous communication is part of them, given the interoperability focus. Notes Dexcom’s press release: “The FDA’s special controls set a rigorous, new standard in our industry and clearly define the process by which other CGM systems may be approved.” This was very smart of Dexcom to get a lower-risk category (so it can innovate faster) that also creates a competitive moat for others – if you don’t meet the rigorous standards, you can't get the 510(k) path. We’ll have more on this soon.

G6 maintains the feature set we’ve expected since ATTD and last month’s call: 10-day wear, no fingerstick calibration, two-hour warmup, use in ages 2+ years (the lowest of any standalone CGM), maintaining the non-adjunctive (insulin dosing claim) in G5, the massively improved one-button applicator, ~28% thinner transmitter (notably flatter profile), acetaminophen blocking, predictive urgent-low-soon alerts, a slightly redesigned mobile app on Android and Apple iOS (see pictures below), and real-time CGM readings sent every five minutes to the G6 app or receiver.

For the first time in Dexcom’s history, G6 does have a mandatory shutoff at 10 days, a move we expected given the labeling and factory calibration. In line with Dexcom’s ATTD 2018 symposium last month, G6 users will have the ability to enter an optional fingerstick calibration, if a user desires to enter one – e.g., if errant sensor values are observed. On the investor call, management emphasized this could be valuable for AID partners. However, in downloading the just-released G6 simulator app, it’s very clear from the menu structure just how much calibration are de-emphasized – a user must go into “settings” and find “calibrate” near the bottom of the menu (under “Apple Health”). This is very smart of Dexcom. The G6 simulator app also showed us that each sensor come preloaded into an applicator, and a calibration code is required for each sensor and captured via photo. We’ll be interested to better understand the startup hassle here, which does seem slightly higher than with FreeStyle Libre’s factory calibration (no codes).

Competitively speaking, however, this puts Dexcom’s G6 on top of Abbott’s FreeStyle Libre on many product features, especially the new 510(k) clearance as an “iCGM” with interoperability in mind. We include a feature-by-feature comparison below – of course, there is tremendous runway for all CGMs to massively expand the underpenetrated CGM market in the US and globally.

Dexcom already has a webpage up at and the aforementioned G6 simulator app on iOS and Android (worth watching the videos in the app). G6 seems like it could launch on the earlier side in Q2, as many pieces already seem to be in place and Dexcom historically launches quite fast. That said, G6 changes every piece of Dexcom’s product, so a controlled rollout would be prudent.

Overall, this is a tremendous, better-than-expected regulatory victory for people with diabetes in the US. Now, patients will have another factory calibrated CGM to choose from – three years ago, we would not have guessed TWO such systems would be out, both with insulin-dosing claims! And moving forward, today’s news is potentially game-changing for the field, opening up a streamlined regulatory process for other iCGMs and systems/software that connect to iCGMs.

Below, we include pictures of G6 from the media kit, a feature comparison with FreeStyle Libre and Guardian Connect, and our questions.

iCGM – Special Controls and Definition

  • Read the FDA’s special controls for iCGM here and our complete analysis hereTo qualify as an iCGM for the new 510(k) path, a device must meet a slew of very specific and rigorous performance characteristics (benchmarks), communication standards, and more. We’ll have more on these soon, but here’s a sample:

    • 70-180 mg/dL: the % of iCGM measurements within 15% of the blood glucose value must be calculated, and the lower one-sided 95% confidence bound must exceed 70%.

    • <70 mg/dL: the % of iCGM measurements within 15 mg/dl of the blood glucose value must be calculated, and the lower one-sided 95% confidence bound must exceed 85%.

    • >180 mg/dL: the % of iCGM measurements within 15% of the blood glucose value must be calculated, and the lower one-sided 95% confidence bound must exceed 80%.

  • G6 achieved this new regulatory path via a de novo application, which cites a new indication for use: “The Dexcom G6 Continuous Glucose Monitoring System (Dexcom G6 System) is a real time, continuous glucose monitoring device indicated for the management of diabetes in persons age 2 years and older. The Dexcom G6 System is intended to replace fingerstick blood glucose testing for diabetes treatment decisions. Interpretation of the Dexcom G6 System results should be based on the glucose trends and several sequential readings over time. The Dexcom G6 System also aids in the detection of episodes of hyperglycemia and hypoglycemia, facilitating both acute and long-term therapy adjustments. The Dexcom G6 System is also intended to autonomously communicate with digitally connected devices, including automated insulin dosing (AID) systems. The Dexcom G6 System can be used alone or in conjunction with these digitally connected medical devices for the purpose of managing diabetes.” The addition of the latter sentences on interoperability are the notable pieces here – very smart of Dexcom to change to the indication and allow for a new regulatory pathway.

  • The FDA defines an integrated continuous glucose monitoring system (iCGM) as “intended to automatically measure glucose in bodily fluids continuously or frequently for a specified period of time. iCGM systems are designed to reliably and securely transmit glucose measurement data to digitally connected devices, including automated insulin dosing systems, and are intended to be used alone or in conjunction with these digitally connected medical devices for the purpose of managing a disease or condition related to glycemic control.”

Dexcom G6 Pictures

Dexcom G6 – Strengths, Weaknesses, Opportunities, Threats (SWOT)


  • No fingerstick calibration, but maintains strong G5 accuracy and non-adjunctive (insulin-dosing) claim
  • iCGM pathway – could enable much faster innovation going forward with lower-risk classification (510(k)), interoperability in mind, and potential high competitive bar.
  • Alarms and real-time data (vs. FreeStyle Libre), plus new urgent-low-soon alerts
  • New one-button applicator significantly improves on prior syringe-like inserter
  • Both Apple and Android apps at launch, plus fully featured smartwatch display of real-time data
  • Acetaminophen blocking
  • Users can choose to enter an optional fingerstick calibration in occasional case of errant sensor value (but quite buried in settings menu).
  • 20-foot Bluetooth transmission range


  • Three-month, reusable transmitter
  • Touchscreen receiver still must be purchased
  • Each sensor comes with a unique code that must be entered via photo (see left screenshot above)
  • Soonest G6-integrated AID product is likely Tandem’s hybrid closed loop with TypeZero (Control-IQ), set to launch in 1H19. Upcoming Tandem PLGS (Basal-IQ) is under review with G5.
  • DME channel can still be a hassle for prescribing and reordering.
  • Dexcom must work with Medicare to begin shipping G6 – cannot immediately switch over from G5 bundle.


  • More pricing flexibility with 10-day wear?
  • Extending to 14-day wear
  • Eliminating required receiver, similar to Guardian Connect
  • Direct-to-watch CGM data transmission from transmitter
  • Moving to disposable transmitter with Verily gen one
  • Insulin automation: decision support for MDI (Lilly), pump systems (Tandem, Insulet, Lilly, Beta Bionics)
  • Coaching work in type 2 diabetes with UHC/Fitbit
  • Ecosystem of apps enabled by public API and now iCGM path


  • Pricing – how much risk is there short-term and longer-term? How will Abbott’s FreeStyle Libre and Medtronic’s Guardian Connect compete with G6 in the payer landscape? How much pricing will Dexcom be willing to give up? How much risk is there in the Medicare channel, where pricing at $8/day seems hard to sustain?
  • Showing outcomes in type 2 diabetes – what will it take to get payers on board? What’s the right business model?
  • How far away is widespread pharmacy distribution?

Dexcom G6, FreeStyle Libre, and Guardian Connect Feature Comparison

In the table below, we’ve summarized the key features of all three approved standalone CGMs in the US. The yellow highlight denotes which system(s) has the advantage on a particular feature, if such an advantage is clear; of course, this is our opinion and some is subjective!


Dexcom G6

FreeStyle Libre (US)

Medtronic Guardian Connect

Fingerstick Calibration

0 – Factory Calibrated


(Optional user calibration when desired, but discouraged in G6 app design)

Each sensor has a unique calibration code – captured via photo

0 – Factory Calibrated


No optional user calibration in cases of sensor inaccuracy


No sensor calibration code required




Not shared today, but likely ~9% or lower – consistent with G5 and ATTD 2018 data


~9% (upper arm)
10.6% (abdomen)


Non-adjunctive – Replaces fingersticks for treatment decisions

Interoperability now part of indications for use

Non-adjunctive – Replaces fingersticks for treatment decisions

Adjunctive – requires fingerstick confirmation

Device Class

Class II, 510(k) - de novo – “Integrated CGM” pathway

Class III, PMA for traditional CGM

Class III, PMA for traditional CGM


2+ Years


18+ years


14+ Years

No Medicare


2 Hours

12 hours

2 Hours

Wear length

10 Days
(minus two hours for warmup)

10 Days
(minus 12 hours for warmup)

7 Days

Mandatory shutoff?

Mandatory shutoff

Mandatory shutoff

Not shared, but presumably sensor can be restarted


Yes – data sent continuously to two display devices – receiver and app

Predictive alerts for lows

None – must scan sensor to see glucose, eight-hour history stored on sensor patch

Yes – data sent continuously to Apple iOS app

Predictive alerts for highs and lows

Data display

Apps for Apple iOS and Android, plus smartwatch apps for viewing RT data

G6 receiver

FreeStyle Libre reader device only


Apple iOS app only; Apple Watch app only mirrors phone notifications

No receiver

Transmitter design and on-body form factor

Small eraser-sized

Three-month use transmitter separate from sensor


~2 stacked quarters
(flat disc)

Fully disposable and integrated with sensor patch


~2 stacked quarters (clamshell)

Rechargeable transmitter separate from sensor

Significant on-body tape


Single-push-button applicator

Abdomen (adults)

Abdomen and upper buttocks (children)

Single-press insertion

Upper arm

Inserter device, requires pulling needle out manually

Abdomen & upper-arm

Pricing without insurance

Not shared today, but G5 pricing is:

~$70-$75/sensor, ~$800-$850 for starter kit (receiver, transmitter, 4 sensors)

Medicare: ~$250/month ($8/day)

~$40-$50 per sensor, depending on the pharmacy (~$129-$159 per).

Reader is ~$85-$100.


Medicare: ~$250/month ($8/day)

Not publicly disclosed


Not shared today. Some pharmacy distribution for G5 exists, but mostly mail order through Dexcom or distributors

Major Retail Pharmacies

Mostly mail order from Medtronic and distributors. No comments ever shared on pharmacy distribution.

Close Concerns’ Questions

Q: How quickly will Dexcom follow with a 14-day wear indication for G6? How quickly will Verily gen one follow (per JPM in January, gen one was expected in late 2018/early 2019)? Today, it seemed that both will be 2019 launches a the soonest, given everything happening with G6. It remains unclear if all G6 users will move over to the Verily product; we’d hope so, but this remains vague.

Q: How long until G6 can launch in the Medicare channel? Management said it has to work with Medicare on this piece (ugh), so G5 bundles will continue shipping for the time being.

Q: Where will Dexcom set G6 pricing? Can it push into the pharmacy with G6, drafting on what Abbott has done with FreeStyle Libre?

Q: How much of a competitive advantage is this new iCGM pathway? How significantly could this speed CGM and related software, wearables, sensor-augmented pump, and AID innovation? How much does this reduce Dexcom’s workload?  

Q: What does iCGM mean for interoperability and AID submissions? How much faster could AID, pump, and dosing app submissions now go? Does this interoperability have implications for DIY closed-loop systems?

Q: Will other approved CGM systems easily meet the special controls for iCGM going forward – e.g., could Abbott’s FreeStyle Libre and Medtronic’s Guardian Connect meet them currently or in subsequent generations? To what extent will these controls prevent a flood of wellness CGMs (we think they will, at least from going the 510K route)?

Q: How seamlessly will other products communicate with G6?  How streamlined will the FDA pathway be for systems that talk to G6 and other iCGMs?


--by Adam Brown, Brian Levine, and Kelly Close