Placebo response in binge eating disorder: a pooled analysis of 10 clinical trials from one research group

The aim of this study was to gain further understanding of placebo response in binge eating disorder.

We pooled participant-level data from 10 double-blind, placebo-controlled, randomized trials of medications for binge eating disorder. The primary outcomes were response (75% reduction in binge eating episodes), cessation of binge eating episodes, change in mean weekly binge eating episodes and binge eating episodes per week.

Of 234 participants receiving placebo, 89 (38%) were responders and 59 (26%) attained cessation. Placebo-treated participants significantly reduced their binge eating. The mean (SD) binge eating episodes per week at baseline was 5.2 (3.2) and at endpoint was 2.2 (2.6). Lower baseline binge eating episode frequency and longer study participation were significantly associated with response and cessation.

Less severe eating pathology at baseline was associated with higher placebo response and cessation rates. Future clinical trials may want to stipulate that participants exceed a threshold of illness severity, which may lead to better placebo and drug separation.