The findings, said the researchers, are an important step toward achieving glucose control with a fully automated closed-loop system for patients with type 1 diabetes.
For the first time, researchers have performed a randomized controlled trial to determine the efficacy of a fully artificial pancreas. The results, recently published in Lancet Digital Health, showed that while the system was not non-inferior to a hybrid artificial pancreas with full carbohydrate counting, patients receiving the fully artificial pancreas were able to stay in the target range for a high percentage of time.
The findings, said the researchers, are an important step toward achieving glucose control with a fully automated closed-loop system for patients with type 1 diabetes. They emphasize that larger studies of the fully artificial pancreas in an outpatient setting are warranted.
The open-label, crossover trial compared the novel faster-action insulin aspart (Fiasp)-plus-pramlintide fully closed-loop system with the Fiasp-alone hybrid closed-loop system with precise carbohydrate counting among 24 patients. The fully artificial pancreas used pramlintide to delay meal glucose absorption at the same rate as the delays in insulin absorption.
Patients receiving the novel fully artificial pancreas stayed in the glucose target range for 74.3% of the time while patients receiving the hybrid artificial pancreas stayed in the target range for 78.1% of the time.
Non-inferiority in the trial was defined as having a 6% margin in the percentage of time in the target range; throughout the trial, more than half of patients had a difference of less than 6% between the 2 systems. Just under half of patients receiving the fully artificial pancreas spent a higher percentage of time in the glucose target range than patients receiving the hybrid artificial pancreas.
Throughout the study, the researchers observed a transient increase in hyperglycemia in the first 2 hours after meals for patients receiving the fully artificial pancreas. The most common adverse event associated with the system was mild nausea, with no serious adverse events or safety concerns reported.
“Studies have shown that nausea is a transient side-effect that tends to dissipate within days to weeks of pramlintide administration,” explained the researchers. “In our study, participants were exposed to pramlintide for an average of 6 days before the intervention, which might have increased individual tolerance to pramlintide but might not have been long enough for the side-effects to completely dissipate before the intervention. A longer outpatient study with the fully closed-loop system could determine whether the gastrointestinal side-effects seen during the interventions will be transient or chronic.”
Tsoukas M, Majdpour D, Yale J, et al. A fully artificial pancreas versus a hybrid artificial pancreas for type 1 diabetes: a single-centre, open-label, randomised controlled, crossover, non-inferiority trial. 2021;3(11):E723-E732.