LY3938577: glucose-sensitive insulin in type 1 diabetes
What this study tests
Eli Lilly's glucose-sensitive insulin candidate in healthy participants and in people with type 1 diabetes. The design is the most revealing detail: the Part D T1D arm retains mealtime insulin lispro alongside LY3938577, which is consistent with testing a glucose-responsive *basal* component — a potential chemical safety floor against lows — rather than a single insulin that replaces both basal and bolus; the registry does not state an intended product profile. Recruiting as of August 2026.
Editorial review: .
Registry checked: 2026-09-17. Registry’s own update: 2026-01-20.
Most recent recorded citation date: 2024-05-15. Only explicit date metadata is included; an undated citation may be newer. This does not mean every claim was reviewed on that date.
Trial status, labels and access can change between reviews. How we review the evidence · How to read the evidence
Evidence at a glance
- Who can enter the study?
- Part A includes healthy participants. T1D cohorts require pump use, HbA1c 6.0–8.5% and low residual C-peptide; Parts B/C require at least two years of T1D and Part D at least one year. Basal-insulin-dose and other protocol restrictions apply. Registered eligibility ↗Enrollment criteria describe who may enter. They do not establish who was analyzed or the denominator for a reported result.
- Reported benefit and results
- None posted. Started 15 May 2024, still recruiting as of August 2026, with registry-estimated completion in September 2026 and estimated enrolment of 118. The registered primary endpoints cover safety and pharmacokinetics rather than a glucose-response efficacy outcome (glucose-infusion-rate pharmacodynamic measures are listed as secondary endpoints), so even a full primary readout would not by itself settle whether the molecule senses glucose usefully in people.Read the result sources and their limitations →
- Important harms
- Read the reported results, safety discussion and original sources. A separate harms summary is not available; this does not establish safety.
- Research access and approval
- Study regions: European Union. A trial listing does not establish product approval or current recruitment at a particular site. Check the study’s current entry requirements.
- What remains uncertain?
- Read the full discussion and original sources for study limitations. Planned endpoints and completion dates are not results.
Research status alone does not establish approval, clinical benefit or local availability.
Primary endpoints
- Safety: adverse events, vital signs and laboratory changes in the specified study parts.
- Pharmacokinetics: LY3938577 concentration, exposure and maximum concentration in the specified study parts.
The full picture
What this study can establish
This early trial includes healthy participants and several T1D cohorts. It measures safety and pharmacokinetics—how the investigational insulin is absorbed and remains in the body. The registered T1D cohorts have narrow pump-use, HbA1c, residual-insulin and dose criteria. Current protocol.
No results are posted. The protocol does not demonstrate that the molecule prevents hypoglycemia, eliminates meal dosing or is suitable for broad clinical use. Product mechanism and clinical benefit require results, not inference from the study phase.
Sources
- [1]A Study of LY3938577 in Healthy Participants and Participants With Type 1 Diabetes Mellitus (T1DM) · Trial registry · 2024-05-15 — Phase 1, n=118 (estimated), started 15 May 2024, recruiting as of Aug 2026. Comparator/background arms include insulin degludec and insulin lispro. No results posted.