A Study of a New Type of Insulin in Participants With Type 1 Diabetes on Insulin Injection Therapy

Inclusion Criteria: * Are male or female participants with type 1 diabetes mellitus (T1DM) on a stable multiple daily injection regimen with a short-acting as well as a long-acting insulin * Have a body mass index (BMI) ranging from 18.5 to 33.0 kilogram per square meter (kg/m²), inclusive, at screening * Have blood pressure, pulse rate, electrocardiogram (ECG), blood and urine laboratory test results acceptable for the study * Have had no episodes of severe hypoglycemia in the past 6 months (requiring assistance in treatment by a second party) * Have venous access sufficient to allow for blood sampling * Have provided written consent and are willing to follow study procedures and commit to the study duration Exclusion Criteria: * Are currently enrolled, or have participated within the last 30 days, in a clinical trial or any other type of medical research judged to be incompatible with this study * Have previously completed or withdrawn from this study * Have or used to have health problems that, in the opinion of the doctor, could make it unsafe to participate in the study * Had blood loss of more than 500 milliliters (mL) within the last month * Are treated with a continuous subcutaneous insulin infusion (insulin pump)