Molecule

Drug Groups

approved; investigational

Description

Rimonabant is an anorectic anti-obesity drug produced and marketed by Sanofi-Aventis. It is an inverse agonist for the cannabinoid receptor CB1. Its main avenue of effect is reduction in appetite. Rimonabant is the first selective CB1 receptor blocker to be approved for use anywhere in the world. Rimonabant is approved in 38 countries including the E.U., Mexico, and Brazil. It was rejected for approval for use in the United States. This decision was made after a U.S. advisory panel recommended the medicine not be approved because it may increase suicidal thinking and depression.

Indication

For use in conjunction with diet and exercise for patients with a body mass index greater than 30 kg/m², or patients wih a BMI greater than 27 kg/m² with associated risk factors, such as type 2 diabetes or dyslipidaemia.

Pharmacology

In the RIO-North America trial, 3040 patients were randomized to receive either placebo or one of two doses of rimonabant (5 mg or 20 mg per day). Patients taking 20 mg rimonabant had significant weigh loss, decrease in waist circumference, improved insulin sensitivity, and increases in HDL cholesterol, compared to patients on placebo.

Toxicity

Almost twice as many people discontinued rimonabant compared with placebo because of adverse events (13.8% vs. 7.2%). These consistently involved psychiatric disorders (8.5% vs. 3.2%), including depression and anxiety. Other common side effects included insomnia, nausea, vomiting, diarrhoea and fatigue.

Affected Organisms

Biotransformation

Hepatic, CYP3A4 involved.

Absorption

Undetermined

Half Life

6 to 9 days with normal BMI and 16 days if BMI is greater than 30

Protein Binding

Almost 100%

References

External Links