Objective: Current insulin infusion sets are approved for 2-3 days of wear; however, glucose sensors are approved for 7-14 days of wear. A commonly reported reason for discontinuing use of CGM within 1 year is not wanting to wear devices on two sites of the body. Any attempt to create a combined glucose sensor and infusion set for closed-loop control requires a set with greater longevity. The coated ConvaTec Infusion Set with Lantern Technology is a new infusion set with multiple slits and coating intended to reduce foreign body response and occlusion from bending or kinking.
Methods: A pilot safety and extended wear tolerability study is being performed at Stanford University. To date, 15 adult subjects on tethered insulin pump therapy using insulin aspart or lispro have completed the study. Each participant places the set and wears it for 10 days or until set failure to establish a maximum length of infusion set wear when 80% of sets are still functional (excluding accidental “pull-outs”). Infusion set failures are based on: (1) Presence of serum ketones with hyperglycemia; (2) Unexplained hyperglycemia, unresolved with correction dose; (3) Signs of infection at the infusion site; (4) Pump occlusion alarm; and (5) Adhesive failure.
Results: Two subjects did not meet failure criteria and were excluded. Of the remaining, 6 (46%) wore the novel infusion set the full 10 days and all sets lasted 7 days or more (mean 8.8 days). 3 premature set failures were associated with persistent hyperglycemia unresponsive to correction boluses on days 7-8, 3 with adhesive failure on days 7-9, and 1 with infection on day 9.
Conclusions: In our previous studies assessing 353 infusion set insertions for 7 days, average length of wear was 5.1 ± 1.7 days. Thus far, the novel set has demonstrated increased longevity. The duration of wear established in this pilot study will be used to perform a masked, randomized controlled crossover study comparing the coated ConvaTec Infusion Set with Lantern Technology against standard infusion sets.
R. Lal: Consultant; Self; Abbott. P.K. Schøndorff: Employee; Self; ConvaTec Inc. L. Hsu: None. M. Heschel: Employee; Self; Unomedical a/s. B.A. Buckingham: Advisory Panel; Self; ConvaTec Inc., Novo Nordisk Inc., Profusa, Inc. Consultant; Self; Medtronic MiniMed, Inc. Research Support; Self; Beta Bionics, ConvaTec Inc., Dexcom, Inc., Insulet Corporation, Medtronic MiniMed, Inc., Tandem Diabetes Care. Other Relationship; Self; Insulet Corporation, Tandem Diabetes Care.