As promised, here is the next in my series on insulin pumps, CGMs, and their relation to JDRF's Artificial Pancreas Project. The Animas Corporation is a company dedicated to creating diabetes products and is a subsidiary of Johnson & Johnson.

The Animas Vibe insulin pump has been available in Europe and Australia since June 2011, and in Canada since September of last year. The Vibe was designed to be used in concert with the DexCom Seven Plus CGM system, and is now compatabile with Dexcom's G4 CGM. In the U.S., the Vibe submission for FDA approval includes only Dexcom's G4. Speaking of FDA approval, Johnson & Johnson submitted its paperwork for the Vibe to get approved last April. As of this writing, It is still in the review process by the FDA.

Interestingly, while the Vibe is used by patients internationally, the Vibe is made right here in the U.S., alongside the company's Ping insulin pump in the Animas plant in West Chester, PA. Once the Vibe is FDA approved, the differences in functionality between the Ping and the Vibe will be minute, with the only difference being integration of the Dexcom CGM. The added menu item of CGM will be located right under Bolus. Within the CGM menu, all the same Dexcom menus are included: High Alert, Low Alert, Rise Rate, Fall Rate, Out of Range and Transmitter (the location to input the ID number for communication). Once a CGM is started, a CGM warning screen will appear to remind the user not to rely solely on CGM readings for making therapeutic adjustments. "Always use fingerstick blood glucose (BG) for treatment decisions" and "CGM Calibration" will be displayed on the screen. This warning will appear every time a new 2-hour CGM startup period has begun. The user must then press OK to confirm the warning and continue with the 2-hour startup session. After pressing OK, the CGM Trend screen will be visible on the pump. The calibration schedule is the same as the stand alone Dexcom G4: at 2 hours and every 12 hours. However, to avoid unusual times for reminders, I typically recommend that individuals calibrate upon waking, before dinner, and before bed.

Recommendations from Dexcom include:
• Always use a fingerstick test
• Do Not use alternative sampling sites (e.g., palm or forearm)
• Always use the same BG meter for calibration for each CGM session 
• Do Not switch your BG meter in the middle of a CGM session
• Follow your BG meter instructions for BG testing
• It is important to follow proper BG testing techniques to ensure accurate calibration values and CGM performance

The CGM within the Vibe will display a reading every 5 minutes and the trend and data graphs can be viewed in 1-, 3-, 6- and 12-hour increments. We all anxiously await the FDA approval of this addition to the integrated pump family.

While the Vibe will be a welcome addition to the technology available, people with diabetes are looking further into the future and many patients, families, and providers are focused on the JDRF’s Artificial Pancreas Project. Most pump companies have some collaboration with JDRF through this project that was launched in 2006, and Animas is included, beginning their partnership in January 2010.   

Animas’ research has focused on the use of the Hypoglycemia-Hyperglycemia Minimizer System (HHM) using the pump and CGM systems.(1) The premise behind the HHM system is to take the current technology of “Threshold Suspend” one step further. Instead of stopping the basal in the event of a low glucose, the algorithm was designed to reduce or prevent glucose excursions outside of a target range by adjusting insulin delivery based on predictions of future glucose trends.  

The algorithm of the HHM System includes two components that both use mathematical approximations. One of these components is the Zone Model Predictive Controller, which is a mathematical approximation of how insulin affects glucose in order to predict near-future glucose trends from recent CGM measurements and insulin dose. The CGM values are inputted into the algorithm every five minutes, and with this information the algorithm determines how much insulin should be delivered to maintain glucose reading within the study target zone (90-140 mg/dL). The second component, the Safety Supervision Model (SSM) uses mathematical approximations to assess continually and reduce the risk of near-future hypoglycemia.  

This feasibility study included adults between the ages of 21 and 65, diagnosed with type 1 diabetes for at least one year, already using an insulin pump for at least six months prior to the study, with A1Cs under 10 percent. The study was designed merely to evaluate the performance of the HHM system in a clinical setting (CRC or clinical research center). The CGM insertion (using the Dexcom Seven Plus system) occurred 2-3 days prior to the CRC visit. The CRC visit lasted approximately 24 hours, which included assessment of the HHM System for approximately 20 hours. Based on this information, the algorithm demonstrated maintained glucose readings between 70-180 mg/dL the majority of the time (69.6 percent overall and 81.8 percent overnight) with very little time spent in the hypoglycemia range (<70 mg/dL).  

Using an algorithm-based system is an incredible step in the direction of a closed-loop insulin pump system. And while I know all of my patients would like a cure, this is a promising stride forward in the technology race to develop a more complete artificial pancreas system.

1. Finan DA et al. Closed-Loop Control Performance of the Hypoglycemia-Hyperglycemia Minimizer (HHM) System in a Feasibility Study. J Diab Science and Tech. 2014, Vol 8(1): 35-42.  http://dst.sagepub.com/content/8/1/35.abstract