FDA approves Medtronic’s Guardian Connect mobile CGM, US launch in May-July with Sugar.IQ app; no dedicated receiver! – March 12, 2018

Executive Highlights

  • Today, Medtronic finally announced FDA approval of Guardian Connect, its standalone, Bluetooth-enabled CGM and paired app. The FDA review lasted two years to the day! A US launch on Apple iOS devices is expected this May-July, on par with 4Q17, on the earlier side of JPM expectations, but still over a year later than originally hoped for. It will initially be a limited launch, followed by broader availability in August-October. The long-anticipated companion “personal diabetes assistant” app, Sugar.IQ powered by IBM Watson, will launch in tandem with Guardian Connect.
  • Guardian Connect does not have a receiver – CGM data can only be viewed on the Apple iOS smartphone app. This is a regulatory milestone in the US and a major win for Medtronic, who has less hardware to deal with and can now market a lower-upfront-cost system.
  • Guardian Connect is approved for 14-75 year olds, uses the seven-day-wear Guardian Sensor 3, and is approved with an adjunctive label. MARD is 9% on the upper arm and 10.6% on the abdomen two fingerstick calibrations per day. The system still uses the familiar rechargeable clamshell transmitter, which now adds Bluetooth.
  • Medtronic has webpages up for Guardian Connect and Sugar.IQ with Watson, focusing on a “smart CGM” – the marketing focuses on the predictive alerts for highs and lows, which come 10-60 minutes in advance. No receiver is the product’s other main advantage relative to Abbott and Dexcom; otherwise, it lags behind one or both systems on smartphone/watch compatibility, daily fingerstick calibrations, length of wear, and on-body form factor.
  • This represents Medtronic’s biggest US launch since the MiniMed 670G, marking a long-awaited entry into the competitive standalone real-time CGM market. This segment is key for driving better outcomes in MDI users, for competing with Abbott’s FreeStyle Libre and Dexcom’s G5, and for reaching Medtronic’s ambitious goal of serving 20 million patients by 2020.

This afternoon, Medtronic announced long-awaited FDA approval of its standalone, Bluetooth-enabled Guardian Connect mobile CGM. A US launch of the sensor and Guardian Connect app on Apple iOS is expected in May-July of this year, the start of Medtronic’s FY19 and in time for Guardian Sensor 3 manufacturing to meet unconstrained demand (per Medtronic’s 4Q17 call). It will initially be a limited launch, followed by broader availability in August-October. The long-awaited Sugar.IQ app (powered by IBM Watson) will launch as a separate companion app on Apple iOS that runs alongside the Guardian Connect app, providing patterns and insights – “Meet Your Personal Diabetes Assistant.” The two products will launch together.

According to the FDA database, approval actually came through last Thursday, March 8 – exactly two years to the day following PMA submission. This launch will come more than a year later than the June 2016 Analyst Day predicted (by April 2017); on the plus side, it’s on par with last month’s expectation to launch “shortly,” and on the early side of the JPM expectation to launch in FY18/FY19 (May 2018-April 2019).

Guardian Connect is approved for patients age 14-75 years with an adjunctive label to complement standard home blood glucose monitoring devices – i.e., not for insulin dosing, as expected given use of the same Guardian Sensor 3 as in the MiniMed 670G. Guardian Connect still requires two fingerstick calibrations per day, has a two-hour warmup, is worn for seven days, and is approved for both abdomen- and arm-wear (per the late February expanded indication). The mobile CGM updates the familiar rechargeable clamshell transmitter to include Bluetooth.

One of the biggest news items in this approval is what it doesn’t include: a dedicated receiver! Guardian Connect will be the first CGM to launch in the US where smartphone display is the only option for viewing data. This is a victory and a regulatory milestone: it reduces the hassle and cost of getting on the system for patients (especially relative to Dexcom’s G5, which requires a receiver), it reduces Medtronic’s need to maintain additional hardware, and it means no gaps in data downloading (users’ mobile CGM data will be sent straight to CareLink). It also shows further FDA comfort with smartphone display of CGM data.

Guardian Connect has a MARD of ~9% (arm wear) and 10.6% (abdomen wear), with ~88% of values within 20%/20 mg/dl of YSI – see the pivotal data from ADA 2016 and the arm-wear data shared in late February. Guardian Connect users may also be requested to provide “occasional diagnostic calibrations.” The 3-4 calibrations per day in the 670G/Guardian Sensor 3 label does not apply here, as Guardian Connect is not powering a hybrid closed loop – good news for Medtronic.

This approval reflects a two-year FDA review (to the day!) following submission on March 8, 2016 – the longest review of a CGM device we can recall in recent memory, especially given the remarkably quick three-month review for the MiniMed 670G/Guardian Sensor 3. We assume the smartphone-only display in Guardian Connect was a major item of discussion, given how new that is for the FDA and for Medtronic. We also wonder if Medtronic had a learning curve to climb on building a Class III CGM display smartphone app – building and maintaining such apps is onerous, especially with the faster-moving cycles of consumer electronics, nuances with phone sound settings, etc. (This was a big learning when Dexcom’s G5 app launched in late 2015.)

Medtronic already has sharp webpages up for Guardian Connect and Sugar.IQ with Watson (see screenshots below). The marketing focuses on a “smart CGM,” given Guardian Connect’s predictive alerts for highs and lows – these come 10-60 minutes before a high or low is predicted to occur, ahead of Dexcom’s current threshold-based alerts. Medtronic says Guardian Connect accurately alerts for 96%+ of hypoglycemic events that actually occur, though the window is quite generous: “within the 15 minute period before or after your blood sugar goes below 70 mg/dl.” This high level of prediction makes for great marketing, but the nuisance factor will be critical to assess in real-world use; the false positive rate is not disclosed, but we’d assume it’s fairly high with a 60-minute horizon and without passively collected insulin-on-board information. Obviously these can be turned on or off as desired.

Sugar.IQ will exclusively be offered for free to Guardian Connect users, meaning 670G and non-Medtronic-CGM users will not have access to the IBM Watson-powered app at launch. This app could emerge as the single biggest driver of this product’s success and differentiation vs. G5 and Libre. (The main other advantage for Guardian Connect is no required receiver.) Sugar.IQ’s user experience looks identical to what we’ve seen at conferences over the past two years (DTM, ADA) – a mix of a chat-like interface with Watson insights and colorful data displays. We wonder if Medtronic will make Sugar.IQ available to other CGMs in the future, perhaps charging a monthly subscription fee for users – this would actually allow it to capture revenue from superior CGM analytics software, even if a user is on another company’s CGM.

Unquestionably, Guardian Connect will be a very big US launch for Medtronic, marking the company’s entry into the standalone real-time CGM market – key for driving outcomes in MDI users, for competing with Abbott’s FreeStyle Libre and Dexcom’s G5, and for reaching its ambitious goal of 20 million patients by 2020. The standalone real-time CGM market is faster-growing and has more globally runway than pumps, but it’s also a new foray for Medtronic – can it transform itself into a CGM-driven business? Can it match the features in G5/G6 and Libre in subsequent generations?

  • Medtronic has seen success with Guardian Connect (with Enlite Enhanced), which launched outside the US in fall 2016. The past three earnings updates – 4Q17, 3Q17, 2Q17 – have all noted strong uptake and utilization of this system OUS, which could bode well for the US entry.
  • Get more details below, including a SWOT analysis of Guardian Connect, pictures, screenshots from Medtronic’s website, our key questions, and previous coverage of Sugar.IQ.

Guardian Connect – Strengths, Weaknesses, Opportunities, Threats


  • No receiver – smartphone-only display reduces startup cost, simplifies launch, and ensures data capture for all users
  • Sugar.IQ with IBM Watson companion app – differentiator to make CGM data more useful and meaningful
  • Guardian Sensor 3 approved for both arm and abdomen-wear
  • Predictive alerts 10-60 minutes in advance of lows/highs
  • Remote monitoring includes text messages, plus a web app that can be accessed from any internet-connected device
  • Medtronic’s payer relationships, especially with Aetna and UHC


  • Adjunctive claim excludes from Medicare reimbursement; Medtronic cannot market “insulin dosing”
  • Reusable transmitter remains a bit clunky and requires a fair amount of additional tape
  • Two daily fingerstick calibrations, with patients also “occasionally” requested to provide diagnostic calibrations
  • Not available on Android
  • No pediatric indication – only approved for 14+ years
  • No Apple Watch app to view real-time data (only notifications)
  • Does not post data to Apple Health


  • New business models, given no receiver and payer relationships?
  • Additional Sugar.IQ features, especially hypoglycemia prediction and therapy Q&A/advice
  • Android app
  • Pediatric indication (<13 years)
  • Guardian Connect should pave the way for a Bluetooth-enabled version of MiniMed 670G/Guardian Sensor 3
  • Reducing daily calibrations
  • Moving to a disposable transmitter


  • Sensor manufacturing – is Guardian Sensor 3 capacity truly solved?
  • Will the predictive alerts have high nuisance factor?
  • Can Medtronic turn itself into a CGM-driven company?
  • Will Sugar.IQ actually emerge as a differentiator? Will the app see sustained engagement?
  • While Abbott FreeStyle Libre and next-gen Libre, Dexcom G5/G6, Senseonics’ Eversense are not necessarily outright threats, they are all strong standalone CGMs

Highlights from Guardian Connect and Sugar.IQ Webpages

  • Based on the Guardian Connect website, CGM notifications will appear on the phone’s home screen and Apple Watch, but there is no dedicated Apple Watch for viewing real-time data. This is planned for a future version of Guardian Connect, and we think it should be fairly high priority – many Dexcom users praise the G5’s Apple Watch and Android Wear apps, which include the ability to see real-time data.
  • The Guardian Connect app will not post data to Apple Health, which is a disappointment. We hope Medtronic continues to move in the direction of interoperability.
  • It appears that the separate Sugar.IQ companion app pulls data from the real-time Guardian Connect app – note the CGM trend and arrow in the Sugar.IQ screenshots below. The apps communicate via the CareLink cloud, and the delay is only a matter of minutes at most – a big win, since we easily could have imagined a retrospective delay here (e.g., a three-hour delay to remain a Class I app, like Dexcom’s Clarity). Our perception is that Sugar.IQ cannot receive CGM data directly from the transmitter, meaning Guardian Connect will need to be run separately on the phone. We’ll be interested to hear how users like the tradeoff – maintaining two apps is annoying, but also allows Medtronic to drive faster innovation with the lower-regulatory-risk Sugar.IQ app.  
    • In the future, we’d love to see Medtronic make Sugar.IQ available to other CGMs – perhaps it would charge a monthly subscription fee (e.g., $2.99), allowing it to capture revenue from users on another company’s CGM!
  • Guardian Connect will enable remote monitoring from a CareLink Connect web app (accessible from any internet-connected device) and via text message alerts – this has been a hole in Medtronic’s CGM/pumps, as the current remote monitoring option uses the older Enlite sensor and requires the MiniMed Connect keychain uploader.
  • “With artificial intelligence technology from IBM Watson Health, the Sugar.IQ assistant continually analyzes how an individual's glucose levels respond to their food intake, insulin dosages, daily routines, and other factors…Together with the Guardian Connect system, the Sugar.IQ assistant can turn difficult-to-determine patterns into personalized, actionable insights that help people with diabetes keep glucose levels in their target range.”


Close Concerns’ Questions

Q: How will US users evaluate Abbott, Dexcom, Medtronic, and (possibly) Senseonics’ standalone CGM systems? Who will add the most users this year in the US?

Q: Will Sugar.IQ be a differentiator for Guardian Connect? Will it be a compelling reason to choose Guardian Connect over other sensors? Will it see sustained use and engagement, given the need to open a separate app?

Q: When will we see a pediatric indication for Guardian Connect? Does the under-FDA-review pediatric 670G/Guardian Sensor 3 data (7-13 years) apply to Guardian Connect, since it’s the same underlying sensor?

Q: How far behind is an Android version of Guardian Connect? Will Medtronic’s partnership with Samsung accelerate progress here?

Q: How quickly will Medtronic update the MiniMed 670G/Guardian Sensor 3 to add Bluetooth and remote monitoring? Will this be out before a competitive hybrid closed loop is available in the US?

Q: Where is Medtronic on reducing daily calibrations and moving to a disposable transmitter for its real-time CGM? How far behind Dexcom’s G6 will these come?

Previous Sugar.IQ Outcomes Data – DTM 2017

  • In Sugar.IQ’s continued ongoing “limited learning launch” phase, 256 users showed encouraging engagement metrics. In an n=136 subset of users (with 2+ weeks of data), Sugar.IQ’s glycemic insights helped increase time in range by a modest 33 minutes per day. Users spent an additional 2% of the day in range (baseline not given, not statistically significant), as well as 14% fewer lows longer than 120 minutes per year (p<0.001) and 3.9% fewer highs longer than 120 minutes per year (p<0.001) – the latter were very strange metrics, and we’d speculate it the more traditional time <70 mg/dl and >180 mg/dl were not significantly changed (given the small bump in overall time-in-range). Of course, reductions in prolonged events more than two hours are very positive and presumably of strong interest to payers. Within a week after a low glucose “insight,” 55% of users had fewer lows, with an overall 2.4% less time spent below target; within a week after a high glucose insight, 54% of users had fewer highs, with an overall 1.7% less time spent above target – we assume the latter were absolute reductions, meaning ~30-minute daily improvements in time spent low/high after insights. These are fairly modest, but presumably the group on the app is doing quite well at baseline. On average, participants in the study used the app 2.1 times per day – indicating it is engaging and could drive good ROI from the pattern recognition. Users “liked” 86% of the nearly 4,700 insights generated in the period, and 68% were logging food (2.8 items/day, on average). This analysis was part of the limited learning launch, from which we saw preliminary data at ADA 2017 (smaller n of 81). At DTM, Medtronic’s Dr. Vigersky emphasized that “simple, judgement-free nudges can lead to sustained behavior improvement.” Aka…“your Jewish mother in an app.” We think Sugar.IQ has done some nice things to pull more insight out of CGM data, particularly the app’s “motivational” insights. How much value will it add to Guardian Connect? Will a non-early adopter population use the app? Will it emerge as a revenue source for Medtronic over time?

Screenshots of Sugar.IQ Insights from ADA 2017

Read the original coverage here.


-- by Adam Brown and Kelly Close