TIRTLE2: acute metabolic effects of tirzepatide in T1D
Recruiting Australian Phase 2 placebo-controlled clamp study of six weeks of weekly 2.5 mg tirzepatide in adults with T1D on AID. It is a mechanistic follow-on to TIRTLE1, not a glycemic-outcome pivotal, and tirzepatide is not approved for T1D.
Primary endpoints
- Change in whole-body insulin sensitivity on a hyperinsulinemic-euglycemic clamp at 6 weeks
Results so far
No results. Recruiting; estimated n=44; actual start 7 July 2026; estimated primary completion 31 December 2027. Last registry update 10 August 2026.
The full picture
TIRTLE2 asks whether a low, short course of tirzepatide changes insulin sensitivity and glucagon responses in T1D before much weight is lost. It does not replace TIRTLE1, and it does not make tirzepatide a T1D treatment. Glucose units in the protocol: time in range 70–180 mg/dL (3.9–10.0 mmol/L); level-2 hypoglycemia below 54 mg/dL (3.0 mmol/L).