A Three-part Study to Evaluate the Safety, Pharmacokinetics and Pharmacodynamics of MK-2640 in Healthy Participants (Part I) and Participants With Type 1 Diabetes Mellitus (Parts II and III) (MK-2640-001)

MK-2640 intravenous infusion administered to participant in a fasted state

RHI 100 units/mL intravenous infusion to maintain target glycemic level

Dextrose 20% or 50% intravenous infusion for approximately 9 or 7 hours, as appropriate to attain a target glycemic level

Insulin aspart subcutaneous injection or intravenous infusion the evening before each period in Parts II and III to achieve/maintain glycemic target.

Rescue medication may be administered for hypotension or mild to moderate infusion reaction. Rescue medication may include epinephrine, antihistamines, steroids, or acetaminophen/paracetamol.