A pragmatic randomized controlled trial (RCT) reported superior weight loss when anti-obesity medications (AOMs) were added to a 1-year employer-based weight management program (WMP+Rx) compared to WMP alone. Evidence regarding sustainability of weight loss, upon trial completion, is lacking. This report aims to evaluate weight loss sustainability upon completion of the RCT.

This retrospective, observational report, analyzed data from subjects post-completion of the previous RCT. The main outcome was the mean change in body weight from baseline (end visit of the previous RCT) to 24 months.

Of 199 subjects included in the RCT, 185 subjects who had pre-trial (prior to the previous RCT) and baseline weight (end visit of the previous RCT) were included in this report. Both groups; [WMP+Rx; 97 subjects, (52.4 %)] and [WMP; 88 subjects (47.6 %)] demonstrated an increase in mean body weight during the observational follow-up period; 5.2 % (95 % CI: 3.4 %, 7 %) and 6.3 % (95 % CI: 4.5 %, 8.1 %) for the WMP+Rx and 1.3 % (95 % CI: −0.6 %, 3.1 %) and 2.1 % (95 % CI: 0.3 %, 4 %) for the WMP, at 12 and 24 months, respectively. Higher percentages of individuals who gained of > 5 % of baseline weight was observed in the WMP+Rx vs WMP group; (47 %) vs (28 %) [odds ratio OR 3.16 (95 % CI: 1.19, 8.37), (P = 0.02)] and (51 %) vs (39 %) [OR 2.85 (95 %CI: 0.93,8.74), (P = 0.067)], at 12 and 24 months, respectively.

Weight loss achieved with WMP with or without AOMs was not maintained at 12 and 24 months. Chronic obesity management is needed for sustainable outcomes.