NCT00584389

The Effect of Rimonabant on Energy Expenditure, Fat Metabolism and Body Composition

• Status: Terminated
• Phase: Phase 4
• Study type: Interventional
• Enrollment: 14 (actual)
• Sponsor: University of Surrey · Academic / Other
• Sex: Female
• Age: 50 Years – 70 Years
• Healthy volunteers: Accepted

Summary

This study will determine in obese subjects the direct effects of the weight loss drug rimonabant (ie independent of weight loss) on energy expenditure, fat metabolism and and body fat distribution. We hypothesise that rimonabant will increase energy expenditure. The fuel for the increased energy expenditure will come from fat. As a result of burning more fat there will be a decrease in fat in blood and an improvement in the body's response to insulin.

Detailed description

In obese subjects (BMI 33-38kg/m2) completing 12 months of treatment with the CB1 antagonist rimonabant (SR141716) there was an average weight loss from baseline of approximately 8.5 kg. These studies also showed the weight loss was accompanied by a decrease in plasma triglyceride (TG), an increase in HDL cholesterol and an improvement in insulin sensitivity measured by HOMA-IR. When adjusted for weight loss 50% of the improvements in TG, HDL cholesterol, and insulin sensitivity was not attributable to weight loss. This suggests that rimonabant has direct effects on fat metabolism. This study will investigate the direct effects of rimonabant (ie independent of weight loss) in a 2 group randomised study. One group will receive rimonabant for 12 weeks and the other group will have a dietary intervention to match the weight loss in the rimonabant group. Measurements of energy expenditure (using indirect calorimetry and Actiheart monitors),fatty acid and triglyceride metabolism (using stable isotope techniques) and body fat distribution (by magnetic resonance imaging) will be made before and after the intervention. To determine the possible mechanisms of the changes in metabolism, gene expression of key regulators of fatty acid metabolism in adipose and muscle tissue and circulating levels of adipokines will be measured.

Conditions

• Obesity

Interventions

Type	Name	Description
DRUG	rimonabant	20mg/d (oral) once daily for 12 weeks
BEHAVIORAL	Dietary intervention	Dietary intervention to match weight loss in group 1. The energy prescription will be based on the estimate of the energy deficit estimated from the weight loss in group one. For example a weight loss of 5kg over 12 weeks equates to an approximate energy deficit of 30,000 kcal or a daily energy reduction of approximately 357 kcal. If this is achieved in group 1 the daily energy target for subjects in group 2 will be daily energy expenditure minus 357 kcal.For the subjects randomised to the dietary intervention group there will be a delay until group 1 subjects have completed the study.

Timeline

• Start date: 2007-07-01
• Primary completion: 2009-04-01
• Completion: 2010-05-01
• First posted: 2008-01-02
• Last updated: 2010-04-19

Locations

1 site across 1 country: United Kingdom