A Randomized Trial of Lorcaserin and Lifestyle Counseling for Maintaining Weight Loss Achieved with a Low-Calorie Diet

Objective: Improving the maintenance of lost weight remains a critical challenge, which can be addressed by long-term behavioral and/or pharmacological interventions.

Methods: This study investigated the efficacy of combined behavioral and pharmacological treatment in facilitating weight loss maintenance (WLM) in 137 adults (86.1% female; 68.6% black; BMI = 37.0 ± 5.6 kg/m ) who had lost ≥ 5% of initial weight during a 14-week low-calorie diet (LCD) program (mean = 9.3 ± 2.9%). Participants were randomly assigned to lorcaserin (10 mg twice a day) or placebo and were provided 16 group WLM counseling sessions over 52 weeks.

Results: At 24 weeks post randomization, more lorcaserin-treated than placebo-treated participants maintained a ≥ 5% loss (73.9% vs. 57.4%; P = 0.033), and the lorcaserin-treated participants lost an additional 2.4 ± 0.8 kg versus a 0.6 ± 0.8 kg gain for placebo (P = 0.010). However, at week 52, groups did not differ on either co-primary outcome; 55.1% and 42.6%, respectively, maintained ≥ 5% loss (P = 0.110), with gains from randomization of 2.0 ± 0.8 kg and 2.5 ± 0.8 kg (P = 0.630), respectively. From the start of the LCD, groups maintained reductions of 7.8% and 6.6%, respectively (P = 0.318).

Conclusions: Combined behavioral and pharmacological treatment produced clinically meaningful long-term weight loss in this group of predominantly black participants. Lorcaserin initially improved upon weight loss achieved with WLM counseling, but this advantage was not maintained at 1 year.