Fully automated closed-loop insulin delivery in adults with type 2 diabetes: an open-label, single-center, randomized crossover trial

• Published in: Nature medicine Vol. 29; no. 1; pp. 203 - 208
• Main Authors: Daly, Aideen B., Boughton, Charlotte K., Nwokolo, Munachiso, Hartnell, Sara, Wilinska, Malgorzata E., Cezar, Alina, Evans, Mark L., Hovorka, Roman
• Format: Journal Article
• Language: English
• Published: New York Nature Publishing Group US 01.01.2023; Nature Publishing Group
• Subjects: 692/163/2743/137/773; 692/699/2743/137/138; Adult; Adults; Aged; Biomedical and Life Sciences; Biomedicine; Blood Glucose; Cancer Research; Closed loops; Cross-Over Studies; Diabetes; Diabetes mellitus (non-insulin dependent); Diabetes Mellitus, Type 1 - drug therapy; Diabetes Mellitus, Type 2 - drug therapy; Female; Glucose; Glycated Hemoglobin; Hemoglobin; Humans; Hypoglycemia; Hypoglycemic Agents; Infectious Diseases; Insulin; Insulin Infusion Systems; Male; Metabolic Diseases; Middle Aged; Molecular Medicine; Neurosciences; Therapy; Treatment Outcome
• ISSN: 1078-8956; 1546-170X
• DOI: 10.1038/s41591-022-02144-z

In adults with type 2 diabetes, the benefits of fully closed-loop insulin delivery, which does not require meal bolusing, are unclear. In an open-label, single-center, randomized crossover study, 26 adults with type 2 diabetes (7 women and 19 men; (mean ± s.d.) age, 59 ± 11 years; baseline glycated hemoglobin (HbA1c), 75 ± 15 mmol mol −1 (9.0% ± 1.4%)) underwent two 8-week periods to compare the CamAPS HX fully closed-loop app with standard insulin therapy and a masked glucose sensor (control) in random order, with a 2-week to 4-week washout between periods. The primary endpoint was proportion of time in target glucose range (3.9–10.0 mmol l −1 ). Analysis was by intention to treat. Thirty participants were recruited between 16 December 2020 and 24 November 2021, of whom 28 were randomized to two groups (14 to closed-loop therapy first and 14 to control therapy first). Proportion of time in target glucose range (mean ± s.d.) was 66.3% ± 14.9% with closed-loop therapy versus 32.3% ± 24.7% with control therapy (mean difference, 35.3 percentage points; 95% confidence interval (CI), 28.0–42.6 percentage points; P  < 0.001). Time > 10.0 mmol l −1 was 33.2% ± 14.8% with closed-loop therapy versus 67.0% ± 25.2% with control therapy (mean difference, −35.2 percentage points; 95% CI, −42.8 to −27.5 percentage points; P  < 0.001). Mean glucose was lower during the closed-loop therapy period than during the control therapy period (9.2 ± 1.2 mmol l −1 versus 12.6 ± 3.0 mmol l −1 , respectively; mean difference, −3.6 mmol l −1 ; 95% CI, −4.6 to −2.5 mmol l −1 ; P  < 0.001). HbA1c was lower following closed-loop therapy (57 ± 9 mmol mol −1 (7.3% ± 0.8%)) than following control therapy (72 ± 13 mmol mol −1 (8.7% ± 1.2%); mean difference, −15 mmol mol −1 ; 95% CI, −11 to −20 mmol l −1 (mean difference, −1.4%; 95% CI, −1.0 to −1.8%); P  < 0.001). Time < 3.9 mmol l −1 was similar between treatments (a median of 0.44% (interquartile range, 0.19–0.81%) during the closed-loop therapy period versus a median of 0.08% (interquartile range, 0.00–1.05%) during the control therapy period; P  = 0.43). No severe hypoglycemia events occurred in either period. One treatment-related serious adverse event occurred during the closed-loop therapy period. Fully closed-loop insulin delivery improved glucose control without increasing hypoglycemia compared with standard insulin therapy and may represent a safe and efficacious method to improve outcomes in adults with type 2 diabetes. This study is registered with ClinicalTrials.gov (NCT04701424). In a randomized, crossover trial in adults with type 2 diabetes, fully closed-loop insulin delivery increased time in target glucose range compared with standard insulin therapy, without increasing hypoglycemia.