The main purpose of this study is to learn more about the safety and efficacy of investigational tirzepatide doses in participants with Type 2 diabetes and obesity that are already taking metformin. The study will last for about 89 weeks.

The study will include a screening period of up to 5 weeks. The primary endpoint will be at Week 44 with a tirzepatide extension until week 80. A safety follow up will be performed approximately 4 weeks after end of treatment.

Inclusion Criteria

• Have a Body Mass Index (BMI) ≥35 kilogram/square meter (kg/m²) at screening.
• Have had stable body weight (±5%) during the 90 days preceding screening.
• Have been diagnosed with Type 2 Diabetes (T2D).
• Have been on a stable treatment of metformin only at least 90 days preceding screening and between screening and randomization with the minimum effective dose of ≥1500 milligram (mg)/day.

Exclusion Criteria:

• Have Type 1 Diabetes (T1D), history of ketoacidosis or hyperosmolar state/coma, or any other types of diabetes except T2D.

• Have had 1 or more episode of severe hypoglycemia and/or 1 or more episode of hypoglycemia unawareness within 6 months prior to screening.

• Are currently receiving or planning to receive treatment for diabetic retinopathy and/or macular edema.

• Have a prior or planned surgical treatment for obesity.

• Use products intended for weight loss including prescription drugs, over the counter (OTC) drugs, and herbal preparations, within 3 months prior to screening.

• Have renal impairment measured as estimated glomerular filtration rate (eGFR) <45 milliliter/min (mL/min)/1.73 m².

• Have any of the following cardiovascular (CV) conditions within 2 months prior to screening.

  • acute myocardial infarction.
  • cerebrovascular accident (stroke).
  • unstable angina .
  • hospitalization due to congestive heart failure, or
  • coronary artery revascularization.

• Have a family or personal history of medullary thyroid carcinoma or multiple endocrine neoplasia (MEN) syndrome Type 2.

• Have a history of chronic or acute pancreatitis.

Anonymized individual patient level data will be provided in a secure access environment upon approval of a research proposal and a signed data sharing agreement.

ata are available 6 months after the primary publication and approval of the indication studied in the US and European Union (EU), whichever is later. Data will be indefinitely available for requesting.

A research proposal must be approved by an independent review panel and researchers must sign a data sharing agreement.