Effectiveness of tirzepatide in Japanese patients with type 2 diabetes but no obesity: A sub-analysis of Hokkaido-TZP study data.

Although tirzepatide efficaciously reduces glucose concentrations and weight, phase 3 trials evaluated patients with a body mass index (BMI) ≥23 kg/m2. Consequently, clinical evidence in patients with type 2 diabetes but no obesity, common in Asia, is insufficient. In this secondary analysis of the multicentre, real-world Hokkaido-TZP study, we evaluated 107 Japanese patients with T2D and BMI <25.0 kg/m2. Over 6 months, tirzepatide significantly reduced HbA1c in all the BMI tertiles (Low, Middle, High). Seven patients discontinued treatment due to adverse events; notably, all belonged to the Low or Middle BMI groups. The overall BMI also significantly decreased, but the reduction was more pronounced in participants with higher baseline BMIs. Multiple regression analysis identified baseline BMI and dietary consultations as significant independent factors contributing to the BMI reduction. Thus, tirzepatide provides effective glycaemic control in patients without obesity, and its weight-lowering effect might be modulated by baseline BMI and lifestyle interventions.