Semaglutide Plus Low-Dose Metformin Combination Therapy for the Treatment of Obesity and Prediabetes in a Woman with Partial Deletion of the X Chromosome Long Arm.

: Over the last two decades, glucagon-like peptide-1 (GLP-1) receptor agonists have dramatically improved the management of type 2 diabetes mellitus and obesity. Currently, little is known about the use of semaglutide (a second-generation GLP-1 receptor agonist) in patients with X chromosome abnormalities. Herein, we describe the therapeutic use of semaglutide in a woman with a partial deletion of the X chromosome long arm (partial Xq deletion) and comorbid obesity. We also conducted a narrative mini-review on overweight, obesity and common metabolic derangements in patients with partial Xq deletions and Turner syndrome.: A 65-year-old Italian woman with a partial Xq deletion, class 1 obesity, insulin resistance, prediabetes, hypercholesterolemia and metabolic dysfunction-associated steatotic liver disease (MASLD) was referred to our Institution for persistent difficulty in managing excess body weight despite regular adherence to different structured physical activity programs and hypocaloric diets. Therefore, we prescribed a combination therapy based on low-dose metformin (500 mg/day) and once-weekly subcutaneous semaglutide (as an adjunct to lifestyle intervention). At 5 months after initiation of the combination therapy, blood tests showed metabolic improvements, including improvement of prediabetes (0.3-percentage-point reduction in glycated hemoglobin [HbA1c] values) and normalization of markers of insulin sensitivity and insulin resistance (QUICKI, HOMA-IR and TyG index). At 8 months, the patient showed substantial weight loss, which amounted to 13.8 kg (percent total body weight loss: 20.95%), and was accompanied by a notable reduction in waist circumference (-14.1 cm). Moreover, body mass index (BMI)-based weight status improved from class 1 obesity to overweight: BMI value of 25.1 kg/mat 8 months vs. 31.8 kg/mat baseline (near-normalization of BMI values). Bioelectrical impedance analysis (BIA) revealed that the patient's overall weight loss consisted of 74.6% fat mass (FM) loss (-10.3 kg) and 25.4% fat-free mass (FFM) loss (-3.5 kg). Despite the expected FFM reduction in absolute terms, percent FFM increased at 8 months (+9.6%). This increase in percent FFM was accompanied by a reduction in percent FM at 8 months (-9.6%), indicating an overall improvement in body composition. Normalization of percent FM and FFM values (28.6% and 71.4%, respectively) was also achieved at 8 months. These body composition changes are in line with those observed in clinical trials investigating the use of semaglutide in patients with overweight or obesity. At 6 months, an abdominal ultrasound also showed the disappearance of the sonographic characteristics suggestive of mild-to-moderate hepatic steatosis. Low-dose metformin (500 mg/day) and subcutaneous semaglutide (up to a weekly dose of 1.7 mg) were well tolerated by the patient.: To the best of our knowledge, this is the first case documenting the effective use of once-weekly subcutaneous semaglutide plus low-dose metformin combination therapy for the treatment of obesity and prediabetes in a woman with a partial Xq deletion. Large prospective cohort studies are warranted to better investigate the safety and efficacy profile of semaglutide (alone or in combination with metformin) in patients with numerical and structural X chromosome abnormalities, comorbid overweight/obesity and related metabolic disorders.