Sanofi's diet pill Acomplia (rimonabant) may not only be better than any other weight-loss drugs currently on the market, but based on its launch in the United Kingdom yesterday, it may be less expensive than most other diet drugs as well.

Sanofi surprised many analysts on June 28th when it announced that a four-week supply of Acomplia would be priced in England at 55.20 pounds ($100.30), or approximately $3.55 for the one-a-day 20 mg pill.

For a novel drug that carries high expectations, this not only is less than some others that have made it to market, but the pricing would appear to make Acomplia less expensive than the last two highly touted diet drugs -- Meridia and Xenical -- which both have been major disappointments.

The normal 10 mg Meridia dosage sells at Walgreen's, the largest U.S. drugstore chain, for $3.86 a pill and the higher 15 mg Meridia pill for those who do not lose weight on the lower dose sells for $5.06.

The 120 mg Xenical pills, which are taken three times daily following major meals, sell at Walgreen's for $2.25 a pill, for a total cost of $6.75 per day.

Even Alli, the low-dose version of Xenical that is expected to be approved by the Food and Drug Administration for over-the-counter sale later this year, is expected to be priced at $60 to $90 for a one-month supply.

The only relatively low-cost diet drug in the bunch is the old prescription standby phentermine, now a generic, which can be bought for about $1 per pill at Walgreen's.

Some analysts believe, however, that the price of Acomplia is likely to be higher in the United States -- perhaps somewhat over $4 per day -- if and when the FDA approves it for sale.

The CEO of Sanofi, Jean-Francois Dehecq, told reporters on June 29th while attending the annual meeting of the European Federation of Pharmaceutical Industries and Associations that the price of Acomplia was likely to vary significantly from country to country.

"Sometimes you will put price in front of volume and vice versa," Dehecq said.

Even though Acomplia has been approved by the European Commission for sale in all 25 member countries, Sanofi in many of these countries now has to negotiate with the individual governments and reach agreement on the sales price of the drug before it can be brought to the market.

During this period when a tremendous demand appears to exist for Acomplia, and the diet drug remains not readily available, it appears that a number of internet pharmacies are going to charge a premium price for the coveted diet pill.