We're studying tirzepatide, a new treatment for adults with type 1 diabetes and obesity or overweight. Type 1 diabetes is when the body doesn't make insulin, and obesity means having too much body fat. Tirzepatide is compared to a placebo (a "fake" treatment) to see how well it works and if it's safe. The study takes about 49 weeks.

To join, you must have had type 1 diabetes and used insulin for at least a year. Your HbA1c (a blood sugar measure) should be between 7.0% and 10.5%. You need a body mass index (BMI) of 25 or higher and a steady weight for 90 days.

However, you can't join if you've had serious blood sugar problems needing hospital visits, eye treatments for diabetes, or pancreatitis. If you've used weight loss drugs recently, you are also not eligible.

• Study lasts about 49 weeks.
• Need to visit clinic regularly for check-ups.
• Risks include possible side effects of tirzepatide.