A Multicenter Study of an Investigational Extended Wear Insulin Infusion Set in Adults with Type 1 Diabetes

To evaluate the function and safety of the SteadiSet™ infusion set over a continuous 7-day wear period in adults with type 1 diabetes.

Participants used a SteadiSet infusion set with a t:slim X2™ insulin pump with Control-IQ™ technology, and either insulin aspart or insulin lispro, for a target of 7 days for 12 consecutive wear periods. Each set removed before 7 days was adjudicated by an independent committee to assess the cause of early removal and to determine whether criteria for primary or key secondary endpoints were met.

There were 260 participants who inserted 3028 infusion sets. For the primary endpoint, the Kaplan-Meier 7-day survival estimate was 95% (95% CI 94% to 96%). For the key secondary endpoint, which expanded the reasons for a failed infusion set, the Kaplan-Meier 7-day survival estimate was 84% (95% CI 82% to 86%). For both endpoints, the P value was <0.001 compared with a prespecified survival rate of 75%. Time-in-range 70-180 mg/dL (TIR) increased through day 3 of set wear and then decreased through day 7, with the average TIR being 70.6% over the entire wear period across all infusion sets, including those that failed. An increase in total daily insulin was observed from day 4 through day 7.

The 7-day survival of the SteadiSet infusion set was very high for the primary endpoint and at an acceptable level with respect to early removal for any reason related to the device.