Up Close with Medtronic’s New MiniMed 640G System in Europe

Twitter summary: Major updates from @MDT_Diabetes on the 640G predictive #insulin suspend for type 1 #diabetes from #ATTD2015

Medtronic Diabetes shared several exciting updates on its MiniMed 640G system and Enhanced Enlite CGM (“Enlite 2”) at this year’s ATTD Conference in Paris. The MiniMed 640G features “SmartGuard” technology, which will suspend insulin delivery if hypoglycemia is predicted to occur within 30 minutes (based on the CGM reading). The system automatically resumes insulin delivery once glucose levels start to recover. The MiniMed 640G is an exciting step beyond the MiniMed 530G/Veo, which could only suspend insulin delivery once hypoglycemia was reached, and it automatically stayed suspended for two hours (unless manually turned back on).

The MiniMed 640G was launched in Australia this January, and is now also available in the UK and Denmark. An FDA submission of the system is expected later this year (the pivotal trial is ongoing), meaning the 640G could launch in the US sometime in 2016, although we think many things will need to go right to achieve this aggressive timeline.

At ATTD, we had the opportunity to handle the new system ourselves and to hear new clinical trial data. Bottom line, hypoglycemia prevention is definitely the strong suit of the 640G, though the pump’s design improvements are an equally big win. We think it’s a particularly valuable option for those with hypoglycemia unawareness, a history of severe hypoglycemia, or who fear nighttime lows.

diaTribe Plays with the 640G – Our Biggest Takeaways

We got the chance to play with the 640G systems ourselves during a Medtronic workshop. Our key takeaways on the system’s design are:

• The 640G’s color, light-adjusting screen greatly improves the user experience. It’s not quite an iPhone-quality screen, but it’s a significant improvement over the gray scale screens of previous Medtronic pumps. The screen is also much larger than on previous pumps. It should be much easier to use at night, since no “backlight” button will be needed to read it in the dark.

• The SmartGuard predictive suspend technology is highly customizable. Patients can now create different settings based on time of day – for instance, more cautious predictive suspend settings at night (e.g., suspend when a value less than 80 mg/dl is predicted) and the feature turned off during the day.

• There are more alarm options on the 640G, a win for more peaceful sleep. Alarms can be set to go off before the low, on the low, or to alert when the system resumes basal delivery, and it’s possible to turn off all three of these alarms for any given time segment (e.g., at night). The ability to shut off all alarms and let the pump work in the background is an exciting prospect of automating insulin delivery – taking much of the burden off patients to constantly confirm and respond to alarms. While some believed the MiniMed 530G annoyed patients with loads of alarms and messages, it’s great that the 640G will allow for more customization.

• The pump can be used with one hand, unlike previous Medtronic pumps that had to be held horizontally and used with two thumbs (e.g., it’s now like holding a smartphone instead of a video game controller).

• Home screen: It’s excellent to see insulin-on-board displayed on the home screen, side-by-side with the CGM data. We loved that feature of the Animas Vibe (see our test drive) and Tandem t:slim (see our test drive) and are glad to see it now incorporated in the 640G. The home screen also has many status icons like battery, reservoir, alarms, etc., and the color-screen allows for useful color-coding of these icons. For example, the reservoir icon is lit up green, orange, or red to indicate how much insulin is left.

• Other new features we learned about: Patients can stop bolus delivery while a bolus is in progress (also like the Tandem t:slim); and users can now create preset boluses (e.g., “Dinner – 2.5 units”) and copy basal patterns.

New Clinical Trial Data on the 640G Shows Significant Benefits for Hypoglycemia

Medtronic also shared results from a 100-patient, two-week clinical trial, in which participants were randomized to use the 640G with or without the SmartGuard insulin suspend technology. Notably, SmartGuard led to a 41% reduction in hypoglycemic events per week (glucose less than 65 mg/dl), and a 41% reduction in time spent in hypoglycemia. The trial did find that time spent in hyperglycemia (above 140 mg/dl) was a bit greater with SmartGuard turned on, though this difference disappeared for time spent above 180 mg/dl. This is perhaps to be expected – since SmartGuard stops the flow of insulin when heading low, there might be a slight elevation in mild hyperglycemia. Larger studies are ongoing to more fully demonstrate how the technology impacts hypoglycemia and A1c.

What’s Next in Medtronic’s Automated Insulin Delivery Pipeline?

A US trial of the MiniMed 640G and new Enlite 3 sensor is ongoing. As we mentioned in our previous diaTribe coverage, Medtronic expects to submit the system to the FDA later this year. The company is hopeful for a launch by April 2016, assuming things go well with the FDA.

At ATTD, we also heard new details on the MiniMed 670G with Enlite 3, which Medtronic has called its “hybrid closed loop” system. In this system, patients would only need to bolus for meals, and the 670G would take care of the rest in the background. Based on the CGM reading, the pump’s software will change insulin delivery to target a blood glucose of 120 mg/dl. The 670G algorithm will be fully integrated within the pump itself, so a patient would only wear the Enlite sensor and the MiniMed 670G pump – no need to carry a separate CGM receiver. A recent clinical trial at diabetes camp demonstrated excellent results at night – patients on the MiniMed 670G spent 80% of the night between 70 and 180 mg/dl, and spent 83% less time at glucose values below 50 mg/dl. Medtronic is further tweaking the algorithm, as it did not do quite as well during the day.   

At the JPM conference in January, Medtronic announced plans to launch the 670G in the US in 2017 and internationally in 2018. It’s exciting to see this progress towards automated insulin delivery, and we hope the company can plow ahead to meet the ambitious timelines. –AB/AJW