Introduction: Clinical trials have shown efficacy of semaglutide for weight loss, but further study is needed in less controlled environments including impacts on body composition.
Materials and methods: This retrospective study included individuals who participated in a weight management programme at a commercial wellness studio receiving once-weekly compounded semaglutide/cyanocobalamin injections from June 2023 to January 2024. Once-weekly semaglutide/cyanocobalamin injected subcutaneously starting at 0.25 mg/0.125 mg and titrated to a maximum dose of 2.4 mg/0.24 mg. The primary endpoint was weight loss at 3 months, with secondary analyses including weight loss percentage, weight loss by body mass index (BMI) class and body composition changes including changes in total fat mass, lean body mass, skeletal muscle mass and trunk adiposity.
Results: A total of 94 individuals were analysed (81F/13M), age in years mean (SD) = 46.57 (10.60). After 3 months, average weight loss was 4.11 (2.77) kg or 4.57% (2.96%). Individuals lost fat mass (2.67 (2.37) kg) and trunk fat mass (1.10 (1.36) kg), while also losing small amounts of lean mass (1.43 (1.41) kg) and skeletal muscle mass (0.88 (0.81) kg). As a proportion of total weight, fat mass decreased while lean muscle mass and skeletal muscle mass increased.
Discussion: This study demonstrates that meaningful weight loss is achievable on semaglutide/cyanocobalamin outside of a closely controlled environment. In addition, body composition improved with losses in fat mass and gains in overall proportion of lean muscle and skeletal muscle.
Keywords: GLP‐1; antiobesity drug; body composition; cohort study; real‐world evidence; semaglutide.
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