Medtronic provided research support to conduct the study. Buckingham reports no relevant financial disclosures. Please see the study for all other authors’ relevant financial disclosures.
A novel extended-wear insulin infusion set was usable for up to 7 days for most adults with type 1 diabetes, with no change in glycemic control and few adverse events, according to findings published in Diabetes Technology & Therapeutics.
In findings from a single-arm nonrandomized trial, adults with type 1 diabetes used an extended-wear insulin infusion set from Medtronic along with their own MiniMed 670G system and insulin lispro or insulin aspart for up to 7 days. The overall survival rate at 7 days was 77.8%, with most participants preferring the extended-wear set to standard insulin infusion sets worn before the trial.
“Since 2017, Medtronic began designing a new insulin infusion set with a longer-wear duration and improved performance based on observations that insulin degradation and preservative loss increased the inflammatory response and insulin-associated inflammation contributed to standard insulin infusion set failure,” Bruce A. Buckingham, MD, active professor emeritus at the Stanford University School of Medicine Center for Academic Medicine, and colleagues wrote. “Iterative advancements relative to earlier insulin infusion set devices designed for 2 to 3 days of wear included a new H-cap connector and tubing with new fluid path design that improve insulin preservative retention and stability, in addition to a new extended-wear adhesive patch that improves skin adherence. The aim of this pivotal clinical trial was to validate a new extended-wear infusion set as safe and effective when used for up to 7 days in adults managing type 1 diabetes.”
At 15 investigational centers in the U.S., researchers enrolled 259 adults aged 18 to 80 years with type 1 diabetes for more than 1 year who used the MiniMed 670G insulin pump system (52% women; mean age, 45 years). Each participant received 12 extended-wear infusion sets to use with their own insulin pump for the duration of the study. Each set was to be worn for up to 7 days, and participants wore 12 consecutive infusion sets during the trial’s duration. The extended-wear infusion set was to be worn for at least 174 hours or until it failed. Any signs of infection were self-reported. Participants answered questions about standard infusion set use and satisfaction prior to the trial. Insulin pump data were uploaded during follow-up visits and used infusion sets were collected. Adverse events were reported at each follow-up visit. The final follow-up included an HbA1c measurement and an exit questionnaire.
Strong survival rate for extended-use infusion set
Of the 259 adults who enrolled, 248 completed the trial. A total of 3,041 sets were used. There were no serious adverse device effects, unanticipated adverse device effects or cases of diabetic ketoacidosis reported. The rate of severe hypoglycemia was 2.5 events per 100 participant-years, the rate of severe hyperglycemia was 104.1 events per 100 participant-years and the rate of skin infections was 20.1 events per 100 participant-years.
The survival rate of the extended infusion set was 83.8% at day 6, and 77.8% at day 7. The failure rate due to unexplained hyperglycemia and device-related severe hyperglycemia was less than 2% for both insulin lispro and insulin aspart.
Compared with baseline, HbA1c with use of the extended-use infusion set declined from 7.2% to 7.1%. Total insulin dosage remained stable across the 7-day wear period.
Most participants extremely satisfied
Participant satisfaction at the end of the study was higher with the extended-use infusion set compared with the standard insulin infusion set (P < .001). At least 66% of participants stated they were extremely satisfied with ease of insertion, comfort of wear, duration of wear, time required to change and convenience of use with the extended infusion set compared with fewer than 40% who were extremely satisfied with the standard insulin infusion set in each category.
“Opportunities for insulin infusion set technology advancement have not only included extending the duration of insulin infusion set wear, but also maintaining glycemic control, while mitigating adverse events across wear duration,” the researchers wrote. “The Medtronic extended infusion set was safely worn for up to 7 days by adults without adversely affecting glycemic control and with favorable user satisfaction.”