The investigators are conducting a study that will investigate the possible mechanisms of
weight loss associated with exenatide treatment and the metabolic characteristics of high
responders (i.e. subjects who achieve greater than 5% weight loss) to exenatide treatment.
The investigators will also examine the magnitude and duration of weight loss among a cohort
of high responders over 52 weeks of treatment, and at 3 and 6 months following treatment.
The mechanisms of weight loss with exenatide are not fully understood, and weight loss
responses to exenatide are highly variable, possibly reflecting distinct metabolic
parameters. By identifying and following a group of obese women who lose greater than 5% body
weight after short-term exenatide treatment, the investigators can gain insights into the
possible mechanisms of weight loss and assess long-term weight loss with this