A Study of Insulin Efsitora Alfa (LY3209590) as a Weekly Basal Insulin Compared to Insulin Glargine in Adult Participants With Type 2 Diabetes on Multiple Daily Injections

Inclusion criteria

• Have a diagnosis of T2D according to the world health organization (WHO) criteria, currently treated with basal insulin and at least 2 injections of prandial insulin per day.
• Are receiving ≥10 units of total basal insulin per day at screening.
• Are receiving ≤2 units/kilogram/day of total daily insulin at screening
• Have an HbA1c value of 7.0% to 10%, inclusive, as determined by the central laboratory at screening
• Have been treated with a stable regimen of one of the following basal insulins used according to local product label with or without noninsulin diabetes therapy for at least 90 days prior to screening

• once daily U-100 or U-200 insulin degludec
• once daily U-100 or U-300 insulin glargine
• once or twice daily U-100 insulin detemir or
• once or twice daily human insulin Neutral Protamine Hagedorn
• Have been treated with at least twice daily dosing of one of the following insulins used according to local product label for at least 90 days prior to screening. One dose of prandial insulin must occur at the evening meal.

• Insulin lispro-aabc
• Insulin lispro (U-100 and U-200)s, IN], U-100 or U200)
• Insulin aspart (U-100)
• Insulin glulisine (U-100), or
• Regular insulin (U-100)
• Acceptable noninsulin diabetes therapies may include 0 to up to 3 of the following with a stable dose for at least 90 days prior to screening

• dipeptidyl peptidase IV inhibitors
• sodium-glucose co-transporter-2 inhibitors
• biguanides (for example, metformin), or
• glucagon-like peptide-1 receptor agonists Note: All noninsulin diabetes therapies must be used in accordance with the corresponding local product label at the time of screening, and participants should be willing to continue stable dosing throughout the study
• Have a body mass index ≤45 kilogram/square meter (kg/m²)

Exclusion criteria

• Have a diagnosis of type 1 diabetes mellitus or latent autoimmune diabetes, or specific type of diabetes other than T2D (for example, monogenic diabetes, diseases of the exocrine pancreas, drug-induced or chemical-induced diabetes).
• Are currently receiving any of the following insulin therapies anytime in the past 90 days:

• insulin mixtures
• insulin human, inhalation powder, or
• continuous subcutaneous insulin infusion therapy, or
• regular insulin U-500
• Have a history of greater than 1 episode of ketoacidosis or hyperosmolar state/coma requiring hospitalization in the 6 months prior to screening
• Have had any episodes of severe hypoglycemia, defined as requiring assistance due to neurologically disabling hypoglycemia, within the 6 months prior to screening
• Have hypoglycemia unawareness in the opinion of the investigator
• Anticipate making changes in personal CGM or flash glucose monitoring (FGM) use (for example, initiation, stopping, or changing device) during the study.
• Have had New York Heart Association Class IV heart failure or any of the following cardiovascular conditions in the past 3 months prior to screening: acute myocardial infarction, cerebrovascular accident (stroke), or coronary bypass surgery.
• Have undergone gastric bypass (bariatric) surgery, restrictive bariatric surgery, or sleeve gastrectomy within 1 year prior to screening