We conducted a randomized, controlled, pilot study to eliminate carbohydrate counting (CC) in adults with type 1 diabetes using an automated insulin (insulin aspart and faster aspart) and pramlintide dual-pump fully closed-loop delivery system. The interventions included 5 arms (n = 11, 8 F, A1C 7.4%) and participants underwent 14 hours of outpatient, free-living, supervised interventions of (i) faster aspart with CC, (ii) faster aspart and pramlintide at a 1u:8µg ratio without CC, and (iii) faster aspart and pramlintide (1:10) without CC (iv) insulin aspart and pramlintide (1:8) without CC, and (v) insulin aspart and pramlintide (1:10) without CC. One participant opted out of the two insulin aspart and pramlintide arms. Prior to each dual-hormone intervention, participants had a 2-4-day drug dose-escalation period. P-values are not reported as this is an underpowered pilot study. During the faster aspart and pramlintide interventions, the mean time in target range (70-180 mg/dL) was 69% (24%) and 77% (13%) with the 1:8 and 1:10 ratios, respectively. During the aspart and pramlintide interventions, the time in range was 71% (15%) and 77% (11%) with the 1:8 and 1:10 ratios, respectively. Compared to the control arm where time in range was 72% (26%), both the insulin aspart and faster aspart arms with the 1:10 ratio provided numerical improvements to time in range. The median time spent below 54mg/dL with each respective ratio was 1.3% (0, 4.5), 0.6% (0, 2.4) on the aspart arms and 0.0% in the faster aspart and control arms. The mean total insulin used throughout the interventions was 38.2 (23.5) units on the control arm, 31.8 (18.4) and 32.5 (17.5) on the faster aspart 1:8 and 1:10 respectively, and 36.6 (26.9) and 32.2 (23.5) on the insulin aspart 1:8 and 1:10 arms respectively. This pilot study suggests that our fully automated dual-hormone delivery system has the potential to alleviate carbohydrate counting without degrading time in the target range; and it will be investigated in a larger subsequent study.


M.Odabassian: None. M.Tsoukas: Speaker's Bureau; Novo Nordisk Canada Inc., Boehringer Ingelheim (Canada) Ltd., Eli Lilly and Company, Janssen Scientific Affairs, LLC, AstraZeneca, Sanofi. E.Cohen: None. M.Pasqua: None. J.Rutkowski: None. A.Haidar: Consultant; Eli Lilly and Company, Other Relationship; Bigfoot Biomedical, Inc., Research Support; Adocia, Dexcom, Inc., Tandem Diabetes Care, Inc.

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