Introduction: the SUSTAIN trials have shown significant improvements in weight and HbA1c levels in people with type 2 diabetes, but the effect and safety of semaglutide in people with type 1 diabetes (T1D) has not been explored yet.

Aims & Methods: In this real-world exploratory study 1.0 mg semaglutide once-weekly was started in adults with T1D and overweight/obesity. To be included, people needed to have stable glycemic control (ΔHbA1c < 0.3 %) , bodyweight (Δ < 3 %) , and insulin type and dose (Δ insulin dose < 5 %) in the last year. Pregnancy or pregnancy wish also was an exclusion criterion. Weight, total daily insulin dose (TDI) and HbA1c were assessed at start and at six months.

Results: Twenty subjects (55 % males, mean age 46.3 ± 9.9 y, diabetes duration 29.6 ± 12.5 y, HbA1c 7.4 ± 0.6 %) were included. Body mass index (BMI) was 33.0 ± 4.4 kg/m2 at baseline, with 80 % of subjects being obese. Two subjects discontinued treatment, both due to gastrointestinal intolerance. Mean bodyweight evolution was -8.5 ± 7.8 kg, ranging between +1.5 and -24.7 kg. Three subjects experienced mild weight gain (ranging 0.2 to 1.5 kg) . Relative weight loss ≥ 5 % was attained in 60 % of cases, and 40 % reached ≥ % weight loss. Mean HbA1c reduction was 0.3 ± 0.7 %, with six subjects (30 %) not showing a reduction in HbA1c. An HbA1c reduction of ≥ 0.5 % was seen in 35 % of cases. A moderate correlation was seen between weight loss and HbA1c reduction (r = 0.52, p = 0.020) . Relative TDI reduction was 13.5 % (IQR 17.8) .

Conclusion: Adding semaglutide 1.0 mg once-weekly in people with T1D was safe, well-tolerated and resulted in promising effects on weight, insulin requirement and glycemic control.

Acknowledgements: JM and HDW claim shared first authorship.


J.Mertens: None. H.T.De winter: None. H.Mazlom: None. F.W.Peiffer: None. E.L.Dirinck: None. N.Bochanen: None. L.Van gaal: Advisory Panel; AstraZeneca, Boehringer Ingelheim International GmbH, Eli Lilly and Company, Merck & Co., Inc., Novo Nordisk. C.De block: Advisory Panel; Abbott Diagnostics, AstraZeneca, Boehringer Ingelheim International GmbH, Eli Lilly and Company, Medtronic, Novo Nordisk, Research Support; Indigo Diabetes, Speaker's Bureau; AstraZeneca, Boehringer Ingelheim International GmbH, Eli Lilly and Company, Novo Nordisk.

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