A Study of LY4057996 in Healthy Participants and Participants With Type 1 and Type 2 Diabetes

This study is testing a new experimental insulin called LY4057996 to see if it is safe and how the body processes it. The study includes healthy volunteers, people with type 2 diabetes, and people with type 1 diabetes. **You may be eligible if...** - You are generally healthy (for the healthy volunteer part) - You have had type 2 diabetes for more than 1 year and your blood sugar control (HbA1c) is between 6.5% and 9.5% - You are on basal insulin therapy (long-acting insulin like glargine or degludec) for at least 6 months at a dose over 10 units per day - You have type 1 diabetes (for the type 1 diabetes part of the study) **You may NOT be eligible if...** - You have significant kidney, liver, or heart problems - You are pregnant or breastfeeding - You have had a recent serious medical event - You are on medications that could interfere with the study drug Talk to your doctor to see if this trial is right for you.