Sanofi-aventis announced its decision to withdraw the rimonabant NDA - New Drug Application - in the United States. Sanofi-aventis is confident in the positive benefit risk ratio of rimonabant 20mg when used in the appropriate population.

According to a company press release, sanofi-aventis will work towards submitting the rimonabant file to the FDA - Food and Drug Administration - at a future date. It will undertake the necessary discussions with the FDA to determine the required modifications to its file. Sanofi-aventis is committed to making all efforts necessary to make rimonabant available to patients in the US market.

Rimonabant is a first in class therapy, discovered and developed by sanofi-aventis, is currently approved in 42 countries and marketed in 20 to treat obesity and overweight patients with associated cardiovascular risk factors.

Acomplia (rimonabant) is approved in European Union for the treatment of obese patients (BMI equal to or greater than 30kg/m2), or those overweight (BMI greater than 27 kg/m2) with associated risk factors such as Type 2 diabetes or dyslipidaemia, in conjunction with diet and physical exercise. The SMPc specifies that approximately 50% of the improved figures observed regarding the levels of HbA1c, HDL cholesterol and triglycerides were independent of that expected from weight loss alone. The lipoprotein fraction significantly enhanced by rimonabant is called "HDL" (HDL: high density lipoprotein), also referred to as "good cholesterol".

Rimonabant is the first and the most studied member of a new therapeutic class of drugs that selectively block the CB1 receptors of the endocannabinoid system (ECS), and the drug's development has deepened scientists' understanding of the ECS. When working normally, this system of receptors in the brain and throughout the body (liver, muscle, abdominal adipose tissue, gastro-intestinal tract and pancreas), among other functions, helps regulate food intake and how the body uses and stores fats and sugars.

In pivotal clinical trials lasting up to two years, rimonabant significantly reduced body weight and waist circumference, a measure of intra-abdominal fat. Rimonabant also improved blood glucose levels, HDLs (the "good" cholesterol), triglycerides (fats in the blood), and insulin sensitivity. The most common adverse events associated with rimonabant were consistent across studies and included gastrointestinal (nausea, vomiting, diarrhea), nervous system (headache, dizziness, paresthesia/hypoesthesia/dysesthesia) and psychiatric disorders (anxiety, insomnia, depressed mood and depression). These adverse events generally occurred within the first 2-3 months, and were often mild to moderate in intensity. Rimonabant benefits from comprehensive post marketing surveillance from more than 110,000 individuals in Europe and other countries who have taken rimonabant.