Medtronic Guardian Mobile system to send CGM data directly to smartphone app – September 24, 2014

Executive Highlights

  • Medtronic is developing Guardian Mobile, a mobile app that will display real-time CGM information via a Bluetooth enabled transmitter and smartphone app. The product will function as a standalone CGM.
  • The plan is to start a pivotal trial of the device later this fall; there are no further details and no official timeline on FDA submission.

At the Health 2.0 conference this week, Medtronic Diabetes’ Samantha Katz provided a first look at Guardian Mobile, a mobile app that will display real-time CGM information via a Bluetooth enabled transmitter and smartphone app. The product is currently in development as a standalone CGM (i.e., no pump necessary), and notably, the smartphone app will function as a primary display device (i.e., patients would only need to have the sensor, transmitter, and their smartphone). The plan is to start a pivotal trial of the device later this fall; there are no further details and no official timeline on FDA submission.

We first heard mention of a device like this in Dr. Fran Kaufman’s presentation at DTM 2013, though it was not discussed in Medtronic’s 2014 Analyst Day. It’s a positive for patients to hear this is in development, since the convenience of smartphone integration will help reduce the burden of carrying multiple devices – and by extension, could expand the population of patients on CGM, which is currently estimated at <10% of type 1s in the US. We also see significant value of such a system for parents and healthcare providers, who could receive push notifications about out-of-range blood sugars. Of course, data overload is the potential drawback, though we imagine users could tailor notification settings to fit their preferences (e.g., Only notify me when a blood sugar is <60 mg/dl for 30 minutes).

In addition to expanding the CGM market and responding to customer demands for greater connectivity, Guardian Mobile also strikes us as a competitive answer to Dexcom’s Gen 5 mobile platform (slated for an FDA submission by the end of 2014 or early 2015, per Dexcom’s 2Q14 call). We’d note that the first public mention of Dexcom’s Gen 5 mobile system came at JPM 2011, which speaks to the challenge of taking Class III medical device data and sending it into the cloud in real time. In addition, communications protocols have been in flux for a number of years, and the emergence of Bluetooth LE as a stable and strong platform has been relatively recent. As a reminder, Dexcom’s Share remote monitoring system – a baby step towards Gen 5 – has been deemed “approvable” by the FDA, and a 2014 launch is expected. As of Dexcom’s 2Q14 call in August, this reflected a 13-month of review. We are hopeful that moving forward, the Agency will move more quickly on cloud-connected diabetes devices.

  • The viral growth in the CGM in the Cloud Facebook group (now at 6,729 members, up from 1,270 members as of June) suggests that sending CGM data to smartphones and other devices resonates strongly with many patients/caregivers. We first heard about this grassroots movement at the DiabetesMine D-Data Exchange at ADA 2014, which falls under the #WeAreNotWaiting movement. Also known as Nightscout, CGM in the Cloud is a crowdsourced remote monitoring platform for people wearing CGM. It is an unauthorized, non-FDA approved, do-it-yourself system consisting of a Dexcom G4 Platinum CGM receiver wired via USB cable to an Android phone. That links up with a database, a cloud server, and an app running on a glanceable display (e.g., parent’s smartphone, patient’s Pebble smartwatch). Online instructions are posted here for putting the system together, and the Facebook group has plenty of pictures and testimonials. Per our discussion with the FDA at ADA 2014, this is technically a regulated medical device, though since it’s crowdsourced, regulation is “tricky.” We would not be surprised to see the FDA attempt to shut this down, though there would be significant pushback from many patients and parents.
  • Guardian Mobile would certainly improve Medtronic’s current standalone CGM offering, Guardian Real-Time, which is only FDA-approved for use with the less accurate Sof-Sensor. An unanswered question is whether Guardian Mobile will use the Enlite 3 sensor. Dr. Bruce Buckingham shared the first-ever unpublished data on product at EASD 2014 last week. The data came from camp studies of the MiniMed 670G hybrid closed-loop system. Overall MARD vs. YSI was a strong 10.8% in a very small eight-patient study (n=383 paired CGM-YSI points). In the more challenging camp setting, Enlite 3 still demonstrated a very solid MARD of 12.5% vs. Contour Next fingersticks (seven patients, n=529 paired points). This represented a marked improvement over the original Medtronic Enlite, which demonstrated an MARD of 14.1% in the clinic and 19% in camp studies (according to Dr. Buckingham’s slides). For context, he noted that the MARD of the Dexcom G4 Platinum was 10.4% in inpatient studies and 16.7% in the outpatient Bionic Pancreas camp study, putting Enlite 3 on more comparable footing (of course, these were not head-to-head studies, so it’s hard to say definitively how they compare).
    • As a reminder, Medtronic’s 2014 Analyst Day highlighted that the Enlite 3 CGM will have “intelligent diagnostics” and “improved accuracy & comfort” – the former could be responsible for the strong accuracy in the camp setting, where inaccurate calibrations are more common. In the past, Medtronic’s public presentations on CGM innovations have emphasized the potential for future systems to have smart algorithms that reject inaccurate fingerstick calibrations. Medtronic’s Enlite 3 sensor is part of a US study of the MiniMed 640G, which is expected to start this month.
  • We look forward to seeing the form factor of the Guardian Mobile transmitter, since Medtronic has used the same clamshell transmitter in recent CGM products – this has obviously been a logical choice for backwards compatibility and manufacturing simplicity, but from a patient perspective, the form factor of this transmitter has some key disadvantages relative to Dexcom’s G4 Platinum transmitter (e.g., shorter transmission range, more finicky connectivity [e.g., LOST SENSOR], and more likely to flop around and dislodge). We’re not sure if the Bluetooth integration will require a larger transmitter form factor or not. 
  • In terms of “future disruptive innovation” in CGM, Medtronic has four goals, per its 2014 Analyst Day: redundant sensing, “fail safe” accuracy, connectivity enhancements, and patient experience. Management said, “From a technology perspective, if you look at our innovation, we can drive sensor technology in a way that others can’t. And we’re committed to that.” Through all of the independent head-to-head studies (e.g., Damiano et al., JDST 2014), Dexcom and Abbott sensors have outperformed Medtronic sensors to date; it remains to be seen how products beyond the original Enlite will stack up against other sensors.
  • FDA submission of Dexcom’s Gen 5 mobile platform is expected by the end of 2014 or in 1Q15, per Dexcom’s 2Q14 call. From a sensor perspective, Gen 5 will use the G4 Platinum sensor built on the same manufacturing line and using the same membranes. The product’s smart transmitter will be Bluetooth enabled and capable of sending data to two devices – (i) to an app on a Bluetooth-enabled device (e.g., smartphone) and (ii) to a dedicated receiver that Dexcom will give to patients (i.e., “in case their backup [device] goes dead”). There has always been some ambiguity related to the need for a dedicated receiver for Gen 5– we wonder if the FDA was not comfortable with a smartphone as the sole CGM display screen. Dexcom has done “lots of human factors work” to build Gen 5’s new user interface, and management has said it will be different from the G4 Platinum’s. The first public mention of a smart transmitter came at JPM 2011, meaning this product has been many years in the making.

Close Concerns Questions

Q: How long will it take the FDA to review Guardian Mobile or Dexcom’s Gen 5?

Q: How significantly will mobile integration boost the penetration of CGM?

Q: Assuming reimbursement was perfect, what fraction of type 1 and type 2 patients will ultimately be willing to wear CGM?

Q: Will CGM eventually outpace the ~30% penetration of pumps in US type 1s?

-- by Adam Brown and Kelly Close