The objective of this study was to describe weight changes in members of a large-scale telehealth obesity-treatment provider who were using antiobesity medications (AOMs). This retrospective observational study analyzed real-world data from adults who initiated AOM treatment with the WW International, Inc. (formerly Weight Watchers) Clinic telehealth program between January 2022 and July 2023 (n = 53,590). The main outcomes were changes in body weight over 12 months, side effects over follow-up, and medication usage patterns. The 53,590 patients who initiated treatment were predominantly female (88.6%), with a mean BMI of 36.9 kg/m2. Mean (SD) treatment duration was 5.3 (4.3) months. Program retention rates based on the number of patients whose time from enrollment was at least 3, 6, 9, and 12 months were 78% (n = 39,907/51,247), 63% (n = 25,515/40,203), 58% (n = 15,472/26,794), and 77% (n = 6459/8394), respectively. Average weight loss was 8.9% at 3 months (n = 37,565), 14.1% at 6 months (n = 24,140), 17.7% at 9 months (n = 15,169), and 19.4% at 12 months (n = 6089). Glucagon-like peptide-1 receptor agonist (GLP-1-RA)-based treatments were predominant. Side effects were consistent with the classes of medications used, and frequency declined over time. This real-world analysis of a telehealth-delivered obesity-treatment program demonstrated outcomes consistent with recent phase 3 clinical trials of AOMs, suggesting generalizability beyond clinical trial and in-person settings.