Studying the Effects of Sibutramine on Eating Behavior

Phase 4

Terminated

Conditions: Obesity

Interventions: Drug: Sibutramine
Drug: Placebo

Registration Number: NCT01170364

Lead Sponsor: New York State Psychiatric Institute

Brief Summary: Obesity is a major public health concern, and the search for useful pharmacologic interventions is ongoing. This study aims to develop a comprehensive series of assessments to directly assess eating behavior, cognitive functioning, and psychological functioning under sibutramine and placebo conditions.

Detailed Description: We will recruit 48 moderately obese men and women seeking weight-loss treatment to participate in a 3-week, randomized, double-blind, cross-over trial of sibutramine 15mg or placebo daily. At the end of weeks 1 and 3, subjects will be asked to participate in a two-day/three-night stay in the Residential Laboratory or Biological Studies Unit of the New York State Psychiatric Institute for comprehensive assessments. The major outcome variable will be the difference in total daily caloric intake between sibutramine and placebo.

Assessments will concentrate on three main components of eating behavior: eating patterns, psychological processing, and neurocognitive function. Eating behavior studies will examine objective variables such as meal size, meal frequency, and subjective aspects of eating such as hunger and fullness. Psychological studies will measure hedonics, including craving, behavioral restraint, and impulsivity. Neurocognitive function assessment will gather information about decision-making, such as the effects of distractors (food and non-food) on task performance. Additionally, drawing from the field of behavioral neuroeconomics, tasks that assess decision-making and the influence of irrational factors on decisions will be assessed. Neuroimaging (fMRI) procedures will also be conducted, and will augment the psychological and neurocognitive assessments by providing a window into the underlying neural circuitry involved.

Following the double-blind phase, participants will be offered open treatment with sibutramine for weight loss.

Recruitment & Eligibility

Status: TERMINATED

Sex: All

Target Recruitment: 14

Inclusion Criteria

moderately obese
stable weight for a minimum of 3 months
systolic blood pressure less than or equal to 140 mm Hg
diastolic blood pressure less than or equal to 90 mm Hg
pulse less than or equal to 95 beats per minute
English language proficiency

Exclusion Criteria

on medications known to affect appetite, weight, or metabolism
current or past history of: binge eating disorder, anorexia nervosa or bulimia nervosa, major depression
current or past evidence of psychosis, bipolar illness
current or past history of alcohol or drug abuse or dependence
known history of learning disorder or developmental disability
current or past attention deficit hyperactivity disorders
low platelet count
current diabetes mellitus
uncontrolled asthma, or controlled only with oral steroids
hypothyroidism not adequately treated
pregnancy, planning to become pregnant, or lactation within the previous 6 months
history of neurological disorder or injury
history of moderate or severe head injury
waist circumference greater than 188 cm
indwelling metallic object, non-removable metal jewelery, medicinal patch or recent metallic ink tattoo
pacemaker
metallic implants
medication patches
significant claustrophobia
color blindness

Study & Design

Study Type: INTERVENTIONAL

Study Design: CROSSOVER

Arm && Interventions

Group	Intervention	Description
Sibutramine	Placebo	Participants in this arm receive sibutramine 15mg for one week followed by two weeks of placebo.
Placebo	Placebo	Participants are prescribed two weeks of placebo, followed by one week of 15mg sibutramine.
Sibutramine	Sibutramine	Participants in this arm receive sibutramine 15mg for one week followed by two weeks of placebo.
Placebo	Sibutramine	Participants are prescribed two weeks of placebo, followed by one week of 15mg sibutramine.

Primary Outcome Measures

Name	Time	Method
24 Hour Measured Caloric Intake	1 week	The primary outcome measure is 24-hour food intake assessed by 24 hour weighed intake after one week of sibutramine administration compared to one week of placebo administration.

Secondary Outcome Measures