It's official that orlistat, a diet pill marketed by GlaxoSmithKline, will become available over-the-counter (OTC) soon. The Food and Drug Administration today announced its approval for the marketing of the weight loss treatment as a non-prescription drug indicated for overweight adults.

The announcement, making Alli the first FDA-approved OTC weight loss medication, came nearly one year after an FDA advisory committee made its recommendation in January 2006 that the federal agency allow the drug to be sold over-the-counter.

"OTC orlistat will be manufactured by GlaxoSmithKline under the name Alli and is indicated for use in adults age 18 years and older along with a reduced-calorie, low-fat diet, and exercise program," FDA says in its statement. By low fat diet, it refers to a diet with less than 30 percent calories from fat.

"We know that being overweight has many adverse consequences, including an increase in the risk of heart disease and type 2 diabetes," said Dr. Douglas Throckmorton, Deputy Director for FDA's Center for Drug Evaluation and Research.   "OTC orlistat, along with diet and exercise, may aid overweight adults who seek to lose excess weight to improve their health."

OTC orlistat with 60 mg of active agent per capsule helps lose weight by blocking absorption of fat and is only for those having a body mass index (BMI) of 27 kg/m2 or more. It is recommended that people on the medication take a multivitamin supplement that contains vitamins D, E, K, and beta-carotene at bed time.

In addition, those who have problems absorbing food, have gallbladder problems and/or are pregnant or breast-feeding should not take the diet pill. For diabetics, the drug may affect blood sugar control.

Early on January 23 of 2006, after reviewing Glaxo's application for selling orlistati on the OTC market, a FDA-appointed advisory committee voted 11 to 3 recommending that the FDA approve the weight loss diet pill containing 60 mg of orlistat (tetrahydrolipstatin) for OTC use in the US.

The OTC diet drug is chemically no different from the existing prescription diet pill called Xenical®, with the former containing 60 mg orlistat and the latter 120 mg per capsule.  The latter was approved by the FDA in 1999 to assist obese people to lose weight. It is the prescription form of the drug orlistat. Alli is not intended to replace Xenical®, which remains available through a physician.

The efficacy of orlistat was demonstrated in clinic trials over six months. On average, those taking three pills a day lost 5.3 to 6.2 pounds. About 50 percent of participants experienced the effect, compared to 26 percent taking a placebo.

However, studies showed the weight loss effect diminished and lost weight came back after use of the drug was discontinued. Those who want to keep the pounds off need to keep taking the pill. The OTC orlistat is intended for use in adults over 18 years old over a period of six months.

Orlistat is generally viewed as safe. However, some of the FDA panelists have concerns that people may abuse the drug. People with eating disorders may use the diet pill to purge fat they eat.

Some worry about the fact that a high percentage of patients in trials were not well informed of the side-effects, which would cause problems in certain individuals. For instance, using orlistat could cause problems for organ transplant patients on the drug cyclosporine as well as those on warfarin, a blood thinner.

Other side effects of orlistat include gas with discharge, oily discharge, increased number of bowel movements, oily spotting, oily or fatty stools, urgent need to have a bowel movement and inability to control bowel movements. About 50 percent of patients on Orlistat experienced some side-effects and seven percent lost bowel control.

To overcome potentially embarrassing side effects, people on the medication will need to take another drug to manage bowel control.

While weight loss is slow, modest and maybe only temporary, the diet pill is costly. According to Glaxo, 90 capsules would cost $55 or $12 to 25 a week. Three capsules a day, used along with three meals, is likely needed to have an effect. To lose 5.7 pounds in six months, one may have to pay $300 or more. The hefty cost may return a loss of less than 5.7-pound weight in 50 percent of the people who use the OTC weight loss diet pi ll.

Use of orlistat does not seem as simple as one pill plus one glass of water equals weight loss. Glaxo said early a 250-page instruction would be offered along with the product to help people. Overall, using orlistat seems quite a task for people, considering it only causes a modest weight loss.

Public Citizen, a not-for-profit organization that defends the interest of consumers issued a statement Wednesday calling the FDA's approval a dangerous move to the public health.  It warned consumers that orlistat causes precancerous lesions in animals, which could lead to development of bowel cancer.

Sidney M. Wolfe MD and Elizabeth Barbehenn, Ph.D., with Public Citizen's Health Research Group, on Jan. 23, 2006 testified before the FDA advisory committee raising their concerns based on certain facts little known to outsiders.

They said that, "The long-term effects of Orlistat on morbidity or mortality associated with obesity have not been established." Glaxo did not report earlier how the diet pill affects blood pressure and serum lipids, which are commonly associated with obesity.

"Although a statistically significant weight loss for Orlistat 60 mg compared to placebo is seen, there is no evidence presented that a modest, transient weight loss due to orlistat will afford any long term clinical benefit either through a change in behaviuor or a reduced risk of serious clinical disease manifest by being overweight," Wolfe and Barbehenn said in their testimony.

"Physicians are increasingly rejecting the prescribing of Orlistat (decrease from 2.6 million US prescriptions in f.y. 2000 to 1.0 million in f.y. 2004). It is clearly in GSK's (and partner Roche's) interest to seek OTC approval. Your committees need to reject this desperate attempt to revive this barely effective drug by an OTC switch."

But Roche, the maker of orlistat, said in recent news release that global sales of xenical (orlistat 120 mg), the prescription form of orlistat for weight loss grew steadily in 2006.

GlaxoSmithKline expects to launch the OTC diet drugl under the brand-name "Alli" in the first half of 2007.

Note:

Orlistat is the drug name.

Xenical® is the trade name or representative name for the prescription drug orlistat.

Alli is the trade name for the over-the-counter drug orlistat.