A Study of Tirzepatide (LY3298176) Versus Placebo in Participants With Type 2 Diabetes Inadequately Controlled on Insulin Glargine With or Without Metformin

Randomized, Phase 3, Double-blind Trial Comparing the Effect of the Addition of Tirzepatide Versus Placebo in Patients With Type 2 Diabetes Inadequately Controlled on Insulin Glargine With or Without Metformin

The purpose of this study is to compare the safety and efficacy of the study drug tirzepatide to placebo in participants with type 2 diabetes that are already on insulin glargine, with or without metformin. Participants will administer tirzepatide or placebo along with their previous glucose lowering medications. The study will last approximately 47 weeks and may include about 23 visits.

Inclusion Criteria:

• Have been diagnosed with type 2 diabetes mellitus (T2DM) and have been treated with insulin glargine (U100), once daily with or without metformin ≥3 months prior to screening visit.
• Have HbA1c between ≥7.0% and ≤10.5%.
• Have a stable weight (± 5%) for at least 3 months before screening.
• Have a body mass index (BMI) ≥23 kilograms per meter squared (kg/m²) at screening.

Exclusion Criteria:

• Have type 1 diabetes mellitus.
• Have had chronic or acute pancreatitis any time prior to study entry.
• Have proliferative diabetic retinopathy or diabetic maculopathy or nonproliferative diabetic retinopathy requiring acute treatment.
• Have disorders associated with slowed emptying of the stomach, or have had any stomach surgeries for the purpose of weight loss.
• Have an estimated glomerular filtration rate <30 mL/minute/1.73 m² [for participants on metformin, estimated glomerular filtration rate <45 mL/min/1.73 m2 (or lower than the country-specific threshold for using the protocol-required dose of metformin per local label)]
• Have had a heart attack, stroke, or hospitalization for congestive heart failure in the past 2 months.
• Have a personal or family history of medullary thyroid carcinoma or personal history of multiple endocrine neoplasia syndrome type 2.
• Have been taking weight loss drugs, including over-the-counter medications during the last 3 months.