Sales of diet drug rimonabant (Acomplia / Zimulti), available in Europe but not approved in the U.S., have turned into a major disappointment for Sanofi-Aventis, which says it does not expect the situation to significantly improve until new clinical trial results are ready for submission to regulators in 2009.

"I am not pleased with the performance of Acomplia," Hanspeter Spek, Sanofi's excutive vice president for pharmaceutical operations, said in reporting total sales of the diet pill amounted to only $30 million in the third quarter of 2007. That is even less than sales of over-the-counter diet pill Alli (low-dose Xenical).

Blaming the FDA, where an expert panel recommended against approval of rimonabant (called Zimulti in the U.S.) out of concern over side-effects, and the European Medicines Agency, which required that a letter of caution be sent to doctors, Spek termed Acomplia's performance "unpleasantly flat."

"Overall, we have to be clear and open with you that, within the current environment, the product will see only marginal progress and the next important step for this product is 2009," Spek told analysts.

But with an estimated 100,000 overweight and obese individuals now taking Acomplia, Spek said the good news is that safety reports do not show "any disturbing signal of an increase of evidence of side effects or any new kind of side effects."

It was concern over psychiatric side-effects of the drug -- including depression and increased incidences of suicidality -- that led to the FDA panel of independent experts recommending against approval of rimonabant in the U.S. Sanofi subsequently withdrew its application rather than waiting for FDA action.

But Spek reiterated again on Oct. 31 that Sanofi ultimately intends to resubmit its application in the United States -- and in the European Union and other nations as well -- based on current clinical trials that Sanofi believes will show rimonabant a valuable drug for treating type 2 diabetes as well as obesity.

"All our clinical trials go in the direction of diabetes," Spek said. He added that by 2009, Sanofi expects to have "a clearcut indication in diabetes where we have a new starting point with all the countries -- with all the institutions -- to get reimbursement" for use of the drug by overweight and diabetic patients.