This is a single-center, randomized, participant-blinded, sham-controlled pilot trial designed to evaluate the adjunctive effect of transcutaneous auricular vagus nerve stimulation (taVNS) in overweight or obese patients who show a suboptimal weight-loss response to incretin receptor agonist therapy. A total of 24 participants will be randomly assigned to receive either taVNS plus tirzepatide 5 mg or sham stimulation plus tirzepatide 5 mg for 12 weeks. The primary objective is to compare the percent change in body weight from baseline to week 12 between the two groups.
Individuals with obesity, or overweight accompanied by at least one weight-related comorbidity (e.g., hypertension or fatty liver disease), who have been receiving incretin receptor agonist therapy for at least 6 months and have achieved ≤10% weight loss during treatment;
Willingness to provide written informed consent.
Presence of diseases that may substantially affect body weight homeostasis, including Cushing's syndrome, uncontrolled thyroid disease (thyroid-stimulating hormone >6.0 mIU/L or <0.4 mIU/L), malignancy, or similar conditions;
Use within the past 3 months of medications, other than incretin receptor agonists, that may significantly affect body weight, including glucocorticoids and antipsychotic agents;
Skin infection or damage involving the auricular area;
Women planning pregnancy in the near future;