LY3938577 Phase 2 in type 2 diabetes (not a T1D result)
The most clinically advanced study of any glucose-sensitive insulin — and it is in type 2 diabetes, not type 1. Lilly is testing LY3938577 against insulin degludec in adults with T2D previously on basal insulin, with time in range as the primary endpoint. It is listed here because it is the best available signal of how far the molecule has got, and it must not be read as evidence in type 1 diabetes.
Primary endpoints
- Change from baseline in glucose time in range 70-180 mg/dL inclusive (non-inferiority versus insulin degludec)
Results so far
None posted. Started 13 October 2025, active and no longer recruiting as of August 2026, target enrolment 100, estimated completion December 2026. Sites in the United States and Argentina.
The full picture
Read the population before the phase. This is Phase 2 — the most advanced trial of any glucose-sensitive insulin anywhere — and every participant has type 2 diabetes. Under this site's standing rule, Type 2 evidence never scores a Type 1 record, and nothing here contributes to the glucose-responsive insulin score. It is catalogued because omitting it would make the class look less advanced than it is, and because "Phase 2" will be quoted in coverage without the qualifier.
Why T2D first is a rational choice, and why it limits what we learn. People with type 2 diabetes generally retain some endogenous insulin and some counterregulation, so a basal insulin that under-delivers at low glucose is safer to test there. That is exactly what makes the result hard to transfer: the hypoglycemia protection a glucose-responsive insulin is supposed to provide matters most in people with no endogenous brake — that is, in type 1.
The endpoint is non-inferiority, not superiority. The trial asks whether LY3938577 keeps time in range at least as well as insulin degludec. A win means "as good as an existing basal insulin". It does not, on its own, demonstrate that the glucose-sensing mechanism does anything — that would require showing fewer lows at matched glucose control, or a measured glucose-response curve.