The Gen3 iLet (iLet) is a purpose-built, fully integrated, bionic pancreas (BP) platform that can operate in a bihormonal, insulin-only, or glucagon-only mode and can receive data from the Dexcom G5 or the Senseonics Eversense implanted CGM. We performed a random-order, cross-over, outpatient study comparing the insulin-only mode of the iLet to usual care (UC) for 7 days each as a bridge from past studies using the BP algorithm on an iPhone connected wirelessly to an insulin pump. The study enrolled adults with T1D who used either MDI (n=12) or CSII (n=22) for their UC. Participants enrolled at Massachusetts General Hospital (n=17) used the Eversense while those at Stanford (n=17) used the G5 as the input CGM signal for the iLet. There was no statistically significant difference between the iLet and UC in % time <54 mg/dl (0.6 [0.2,1.1] vs. 0.6 [0.1,1.2], p=0.87) or mean CGM glucose (155±12 vs. 162±26 mg/dl, p=0.097). The iLet significantly increased % time within 70-180 mg/dl vs. UC (70.1% vs. 61.5%, p=0.006). The mean insulin TDD was not significantly different between iLet and UC (44±20 vs. 42±20 u/day). No serious adverse events occurred during either arm. Several device issues occurred that led to changes in the Gen4 iLet under development to improve safety and usability in pivotal trials. These results suggest that the iLet, using either the Eversense or G5 CGMs, may provide safe and effective glucose control to users with MDI or CSII as their UC.

Disclosure

R.Z. Jafri: None. C.A. Balliro: None. J. Sherwood: None. M. Hillard: None. L. Ekhlaspour: None. L. Hsu: None. R. Selagamsetty: Employee; Self; Beta Bionics. Other Relationship; Self; Boston University. J.R. Costik: Board Member; Self; Nightscout Foundation. Employee; Self; Beta Bionics. Employee; Spouse/Partner; Ortho Clinical Diagnostics. J. Sloane: None. B.A. Buckingham: Advisory Panel; Self; ConvaTec Inc., Novo Nordisk Inc., Profusa, Inc. Consultant; Self; Medtronic MiniMed, Inc. Research Support; Self; Beta Bionics, ConvaTec Inc., Dexcom, Inc., Insulet Corporation, Medtronic MiniMed, Inc., Tandem Diabetes Care. Other Relationship; Self; Insulet Corporation, Tandem Diabetes Care. F. El-Khatib: Employee; Self; Beta Bionics. Stock/Shareholder; Self; Beta Bionics. E. Damiano: Advisory Panel; Self; Novo Nordisk A/S. Board Member; Self; Beta Bionics. Employee; Self; Beta Bionics. Stock/Shareholder; Self; Beta Bionics. Stock/Shareholder; Spouse/Partner; Beta Bionics. Other Relationship; Self; Ascensia Diabetes Care, Senseonics. S.J. Russell: Advisory Panel; Self; Companion Medical, Unomedical a/s. Consultant; Self; Flexion Therapeutics. Research Support; Self; Beta Bionics, MITRE Corporation, Novo Nordisk A/S, Zealand Pharma A/S. Other Relationship; Self; ADOCIA, Ascensia Diabetes Care, Ascensia Diabetes Care, Lilly Diabetes, Roche Diabetes Care, Senseonics.

Funding

National Institute of Diabetes and Digestive and Kidney Diseases (UC4DK108612)

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