FRI654 Concentrated Regular U-500 Insulin In An Automated Insulin Delivery System: A Case Report

Abstract

Abstract Disclosure: J. Aurora: None. A. Saraswat: None. Background: Concentrated regular U-500 (U-500R) insulin is commonly used in patients with T2DM who are highly insulin-resistant, requiring more than 200 units of insulin per day. Utilizing U-500R reduces the number of daily injections, decreases injection volume, and improves cost effectiveness. There have been clinical trials using U-500R for continuous subcutaneous insulin infusion (CSII), particularly in Omnipod which has been shown to improve glycemic control and patient satisfaction without an increase in hypoglycemia (1). In addition, U-500R administration via multiple daily injections (MDI) and an investigational U-500R CSII, have been compared and demonstrated improved glycemic control with both modalities, but an increase in nocturnal hypoglycemia with CSII (2). Automated insulin delivery (AID) systems, or hybrid closed loop systems, have not formally been studied in patients with T2DM using U-500R. We present a case of a patient with T2DM with high insulin resistance using U-500R with Omnipod 5 AID system. Clinical Case: A 54-year-old female with T2DM with high insulin resistance was initially on Omnipod Dash with U-100 insulin lispro with baseline A1c 12.1%. She was transitioned to Omnipod 5 in 2022, and over 4 months A1c improved to 8.8%, GMI 8.8%, TIR 38%, TAR 62%, TBR 0%, CV 35.9%, and automated mode 97%. However, her total daily dose was 134 units leading to pod changes every 1.5 days. She expressed interest in switching to U-500R to reduce pod changes while utilizing her current CSII technology. We switched to U-500R, continued automated mode, increased her 24-hour BG target from 120 mg/dL to 130 mg/dL to reduce hypoglycemia risk, and increased her active insulin time from 3 to 6 hours to reflect U-500R kinetics. After 4 weeks, her GMI improved to 8.0%, TIR 47%, TAR 52%, TBR 1%, CV 45.9%, and automated mode 94%. Although nocturnal BG readings were normal, ranging from 70-130 mg/dL, she was having nightly symptoms of relative hypoglycemia. We then adjusted her BG target overnight to 150 mg/dL, which kept BG between 80-130 mg/dL with resolution of her symptoms. Conclusion: U-500R proved to be safe and effective with Omnipod 5 AID. Despite setting a higher BG target, the algorithm continuously kept BG well below this, particularly overnight. However, the safety mechanisms incorporated with the CSII suspended insulin delivery for predicted hypoglycemia. Further research will be required to adapt the automated dosing algorithm to U-500R to reduce the risk of nocturnal hypoglycemia.