Nov. 5 (Bloomberg) -- Sanofi-Aventis SA, France's largest drugmaker, is halting all human trials of the Acomplia obesity medicine after health authorities in a few countries requested local tests be stopped.

Officials in countries including France demanded an end to research after European regulators last month deemed the pill too dangerous for sale. The ending of those trials, which in France included about 500 patients, ``compromised the feasibility'' of the global clinical program, Sanofi spokesman Jean Marc Podvin said in an interview.

``It's over,'' he said.

The failure of Acomplia threatens the development of new medicines to fight obesity. Merck & Co. said earlier this month that its experimental treatment taranabant, in the same class of medicines as Acomplia, won't make it to market because it makes people depressed and irritable. Pfizer Inc., the world's biggest drugmaker, stopped early-stage work on obesity treatments as part of an overhaul of its research department.

Patients enrolled in Acomplia tests should consult investigators to discuss treatment, the Paris-based company said in a statement today. The decision doesn't alter Sanofi's forecast for 2008, it said.

The London-based European Medicines Agency, which approved Acomplia in 2006, recommended the suspension of sales because the drug's risk of psychiatric side effects outweighed any benefits. Acomplia failed to win the backing of a U.S. advisory panel last year.

To contact the reporter on this story: Trista Kelley in London at tkelley2@bloomberg.net

Last Updated: November 5, 2008 11:41 EST