Trial results for the Phase 3 study (NCT05463744) comparing insulin efsitora alfa to insulin degludec in participants with Type 1 Diabetes were posted on ClinicalTrials.gov on 2025-06-24. The study found that at Week 26, insulin efsitora alfa led to a -0.51% reduction in HbA1c, compared to -0.56% for insulin degludec, with a least squares mean difference of 0.052% (95.0% CI: -0.077 to 0.181).
Background
The study, titled "A Study of Insulin Efsitora Alfa (LY3209590) Compared With Insulin Degludec in Participants With Type 1 Diabetes Treated With Multiple Daily Injection Therapy," aimed to evaluate the safety and efficacy of insulin efsitora alfa against insulin degludec for managing Type 1 Diabetes.
Trial design
The Phase 3 study (NCT05463744) was a completed trial that enrolled 692 participants with Type 1 Diabetes. The study compared 500 U/mL insulin efsitora alfa with 100 U/mL insulin degludec in participants receiving multiple daily injection therapy. A key outcome measured was the change from baseline in Hemoglobin A1c (HbA1c) at Week 26 for noninferiority analysis.
Key results
The trial results showed comparable glycemic control and hypoglycemia rates between the two insulin treatments:
- For "Change From Baseline in Hemoglobin A1c (HbA1c) at Week 26 [Noninferiority Analysis]", the least squares mean change was -0.51% (Standard Error: 0.0469) for 500 U/mL insulin efsitora alfa and -0.56% (Standard Error: 0.0463) for 100 U/mL insulin degludec. The LS Mean Difference was 0.052% (95.0% CI: -0.077 to 0.181).
- For "Change From Baseline in Hemoglobin A1c (HbA1c) at Week 26 [Superiority Analysis]", the LS Mean Difference was 0.052% (95.0% CI: -0.077 to 0.181) with a p-value of 0.432.
- Regarding "Percentage of Time in the Blood Glucose Range Between 70 and 180 mg/dL [3.9 and 10.0 mmol/L] From Week 23 to Week 26", the least squares mean was 52.54% (Standard Error: 0.691) for insulin efsitora alfa and 52.85% (Standard Error: 0.684) for insulin degludec. The LS Mean Difference was -0.31% (95.0% CI: -2.22 to 1.6) with a p-value of 0.751.
- The "Nocturnal Hypoglycemia Event Rate" was 1.99 events per year (Standard Error: 0.180) for insulin efsitora alfa and 1.96 events per year (Standard Error: 0.177) for insulin degludec. The Relative Rate was 1.02 (95.0% CI: 0.79 to 1.31) with a p-value of 0.9.
- At Week 52, the "Change From Baseline in HbA1c [Noninferiority Analysis]" showed a least squares mean change of -0.38% (Standard Error: 0.0484) for insulin efsitora alfa and -0.40% (Standard Error: 0.0479) for insulin degludec. The LS Mean Difference was 0.024% (95.0% CI: -0.11 to 0.157).
- For "Change From Baseline in Fasting Blood Glucose", the least squares mean change was -26.67 mg/dL (Standard Error: 2.247) for insulin efsitora alfa and -25.45 mg/dL (Standard Error: 2.222) for insulin degludec. The LS Mean Difference was -1.22 mg/dL (95.0% CI: -7.38 to 4.93) with a p-value of 0.697.
What this means
The results of this Phase 3 trial indicate that insulin efsitora alfa provides glycemic control comparable to that of insulin degludec in individuals with Type 1 Diabetes. The similar reductions in HbA1c at both Week 26 and Week 52, along with comparable time in target blood glucose range and nocturnal hypoglycemia event rates, suggest that insulin efsitora alfa could be an alternative treatment option for this patient population. The non-inferiority analyses, while not specifying a margin, show very small differences and confidence intervals that cross zero, supporting the conclusion of similar efficacy and safety profiles for these key outcomes.
Source
The information for these trial results was obtained from ClinicalTrials.gov, a public database of clinical studies. The results for study NCT05463744, titled "A Study of Insulin Efsitora Alfa (LY3209590) Compared With Insulin Degludec in Participants With Type 1 Diabetes Treated With Multiple Daily Injection Therapy," were posted on 2025-06-24 on clinicaltrials.gov.