Pfizer, Sanofi-Aventis End Antiobesity Drug Trials

Pfizer is discontinuing the Phase III development program for its investigational compound (CP-945,598) for weight management. CP-945,598 is a selective antagonist of the cannabinoid type 1 (CB1) receptor. The company has decided to discontinue the development program based on changing regulatory perspectives on the risk/benefit profile of the CB1 class and likely new regulatory requirements for approval.
   
“While confident in the safety of the compound, we believe that this is the appropriate decision based on all available information regarding this class of agents, as well as recent discussions with regulatory authorities,” said Martin Mackay, president, Pfizer Global R&D. “As part of our ongoing portfolio prioritization, we will refocus research and development resources on high priority therapeutic areas that address an unmet medical need and have a high probability for success.”
   
Sanofi-Aventis is also discontinuing all trials of its obesity drug, Acomplia. According to a Sanofi-Aventis statement, the decision was made “in light of recent demands by certain national health authorities.”
   
The company recently suspended sales of Acomplia in Europe following the recommendation from the EMEA to temporarily suspend sales because of risks that include depression, anxiety and stress disorders. The drug had been marketed in 18 EU countries since 2006.
   
The FDA rejected the drug last year after a panel of advisers recommended doing so, citing Acomplia’s increased risk of suicidal thoughts.
   
More than 700,000 overweight and obese people around the world have been treated with Acomplia, gaining significant health benefits, according to Sanofi-Aventis. The company had been testing it for use in various types of patients including a possible treatment for cigarette smoking cessation. The drug is believed to work by blocking the same pleasure centers in the body that are stimulated when marijuana smokers get very hungry.