As a drug that should theoretically trigger huge sales, the preliminary figures are "pretty underwhelming," said Steve Brozak, an analyst with WBB Securities.
The problem may be that the drug's marketing campaign stresses the need to transform eating and exercise habits for it to be effective, Brozak said. That's not easy to accomplish through advertising, he said.
Additionally, those willing to make lifestyle changes are likely not interested in diet pills, Brozak said.
Still, first year sales point to a "healthy business" that can be sustained and grown dramatically as new users try the drug, said Joe Cadle, director of marketing for Glaxo's consumer health division.
"We're the only company with an over the counter product that helps treat something that affects 140 million people," Cadle said. He declined to say how many repeat users there were for alli.
In its marketing, Glaxo is careful to warn consumers alli is not a magic pill, but an aid for those willing to commit to a healthy lifestyle.
The drug comes in "starter kits" containing a food journal, a healthy-eating guide and a fat and calorie reference guide. A 60-capsule kit costs about $50 while a 90-capsule pack costs about $60.
In clinical trials, people using alli lost an additional 2 to 3 pounds for every 5 pounds lost through diet and exercise. When taken with meals, the drug blocks the absorption of about one-quarter of any fat consumed. That fat — about 150 to 200 calories worth — is passed out of the body, potentially resulting in loose stools.
GlaxoSmithKline is betting alli will become a major moneymaker. At the time of the drug's launch, the company estimated it would eventually sell between 5 million and 6 million kits annually, translating to at least $1.5 billion in annual retail sales. This year, the company spent $150 million on marketing alli, making it one of the drug maker's biggest campaigns to date.
"As people meet their maintenance goals, they'll share their success stories and get new people to try it," Cadle said.
Another hurdle for Glaxo will be overcoming consumers' distaste for the drug's unpleasant side effects, such as leakages and oily discharges. Marketing material prior to the drug's launch stressed the importance of keeping meals under 15 grams of fat to avoid effects. Educational pamphlets even recommend people start the program when they have a few days off work, or to bring an extra pair of pants to the office.
The warnings turned into fodder for late night comics.
Now Glaxo is focusing on telling people that side effects can be avoided if the drug is used properly.
"They really need to understand the (gastrointestinal) treatment effects are not automatic," Cadle said.
In fact, he said the side effects help some users by signaling when they're not eating right.
Being upfront about the side effects may provoke jokes in the media. Yet failing to do so could bring about a backlash from surprised consumers, as it did for the prescription version of the drug Xenical by Roche Holding. That drug contains twice the dosage of alli.
About half of patients in clinical trials for alli experienced similar gastrointestinal side effects.
Labeling indicates alli is appropriate for anybody who is overweight, or has a body mass index of 25 or higher. Two-thirds of the U.S. population is estimated to be overweight or obese. A body mass index over 30 is considered obese.