Subcutaneous Pharmacokinetic Evaluation of Monomeric Insulin and Lyumjev in Adults With Type 1 Diabetes

The SPEED study is a randomized, crossover pilot study evaluating the pharmacokinetics of novel insulin formulations in adults with type 1 diabetes. The study compares two experimental insulin formulations (diluted U-200 Humalog and U-500 Humulin with sterile water, mannitol and EDTA) against commercially available U-100 Lyumjev to determine if these modifications can improve insulin onset and duration of action. Twenty participants will complete three study visits, each separated by at least48 hours. At each visit, participants will receive one of the three insulin formulations (0.20 u/kg) via subcutaneous injection following consumption of a standardized mixed meal. Blood samples will be collected frequently over 6 hours to measure insulin concentrations and assess pharmacokinetic parameters, including time to maximum concentration (Tmax), maximum concentration (Cmax), elimination half-life, and area under the curve. The study aims to address limitations of current insulin formulations used in automated insulin delivery systems, which are too slow to provide optimal meal coverage without pre-meal dosing. By reducing zinc content through EDTA chelation and decreasing metacresol concentration through dilution, these novel formulations may offer faster onset and shorter duration of action, potentially improving glucose control in people with type 1 diabetes using insulin pump therapy.