21-PUB: GLP-1 Receptor Agonist–Based Therapy in Early Type 1 Diabetes

Introduction and Objective: Pancreatic β-cell function can still be preserved in most of the new onset of type 1 diabetes (T1D). But there are few data about whether GLP-1RA might be effective in early T1D. We retrospectively analyzed anti-GAD antibody (GADA) positive individuals who initiated GLP-1RA and basal insulin combination therapy. Methods: We recruited 7 patients (male; n=0, female; n=7) who were admitted to our hospital from 2019 through 2025 because of new onset of T1D with GADA positive. Liraglutide (Lira) was started from 0.3mg, then increased up to 0.6mg. Combined use of basal insulin was adjusted to achieve fasting plasma glucose (FPG) ~ 100mg/dL. Prandial insulin was used while the metabolic dysfunction existed with ketone body positive. Results: 1) At the time of diagnosis, glucose level was 408.1±159.7mg/dL, HbA1c 12.9±2.7%, BMI 19.7±2.9kg/m2, and age 56.6±19.0 (30~79) yrs-old. When FPG first got to ~ 100mg/dL, fasting C-peptide (F-CPR) was 0.65±0.36 (0.27~1.06) ng/mL. Soon after daily glucose profiles were improved, F-CPR was 1.03±0.55 (0.30~1.94) ng/mL. On this therapy, prandial insulin was used in 4 persons up to 16.8±8.8U/day, but it was all eliminated in 2 weeks. Basal insulin was used up to 11.7±7.4 (4~24) U/day, but it was reduced to 5.9±4.7U/day at 1st month (M) and to 4.6±3.7U/day at 3rd M. Average HbA1c was improved to 6.2±0.6% at 3rd M, and 6.1±0.4% at 6th M by this GLP-1RA based therapy. 2) In (52 yrs-old) person, HbA1c had been maintained ≤6.6% from 3rd through 62th M. The other (39 yrs-old) person has been attaining Time in Range 98~100% from 3rd to 8th M. Although deterioration could be observed in persons with longer period of treatment, (65 yrs-old) person could have attained HbA1c<7.0% until 26th M by GLP-1RA mono-injection therapy. But after 28th M, HbA1c abruptly worsened. She gradually needed to shift to basal bolus insulin injection therapy because of β-cell depletion (72th M; CPR<0.03ng/mL). Conclusion: Although whether GLP-1RA could preserve β-cell function is not well known, but it can be effective in new onset T1D. It could help people with T1D much easier to control diabetes. Disclosure K. Kashima: None. C. Kojima: None.