This study is about a medicine called ZT-01 that might help people with Type 1 Diabetes (T1D) who get low blood sugar (hypoglycemia) at night. Hypoglycemia means having too little sugar in the blood, which can be dangerous. ZT-01 works by increasing a hormone called glucagon during low blood sugar, which might help avoid these low sugar episodes.

Participants will use a special tool called a Continuous Glucose Monitor (CGM) to check their sugar levels for two 4-week periods. They will inject ZT-01 before bed, trying different doses, and also use a fake medicine (placebo) to compare effects. They won’t know which one they are using each time. They will keep using their own methods to check sugar and give insulin. They need to keep a diary and share CGM data through a study phone.

If they share their own CGM data, they will have 6 visits and 2 calls over 16 weeks. If not, they’ll wear the study CGM for 4 more weeks and have one extra visit. Blood and urine tests, blood pressure, temperature, and heart checks will be done. Some might join a sub-study needing overnight stays.

• Study lasts about 16 weeks
• 6-7 visits and 2 phone calls
• Chance to help understand ZT-01 effects