FDA Approves Diet Drug but Warns of Risks

A scant two months after removing two popular diet drugs from the market, the Food and Drug Administration announced Monday that it has approved the first in a new generation of anti-obesity drugs that attack fat in a whole new way--but not without risk.

The new compound, sibutramine, which will be marketed under the name Meridia, works by enhancing the brain’s natural appetite-regulating chemicals, allowing them to act longer.

But the new drug is not without side effects. Meridia can cause increases in blood pressure and, because it is believed to be psychologically and physically addictive, it is expected to be more tightly controlled and subject to regulation by the Drug Enforcement Administration.

It is not expected to be available for several months because of its pending scrutiny by the DEA.

In September, the FDA removed fenfluramine, sold as Pondimin, and dexfenfluramine, sold as Redux, after their use was linked to potentially life-threatening heart valve problems. Fenfluramine was part of a widely used, although unapproved, drug combination known as fen-phen. The other drug, phentermine, is still on the market.

The banned drug dexfenfluramine worked by causing an increase in the release of the brain chemical serotonin, which made patients feel full.

The new drug, known as a neurotransmitter re-uptake inhibitor, works outside the brain cells to prevent naturally produced serotonin from being reabsorbed, essentially making the feeling of fullness last longer.

About 58 million Americans are overweight, and obesity contributes to the deaths of an estimated 300,000 Americans annually, the FDA said.

For many consumers, diet pills have long proved a popular and easy way to shed extra pounds. However, most experts have warned that there is no quick or easy way to lose weight and have advised consumers to include calorie control and exercise as part of their weight-loss programs.

*

Although the new drug does not appear to cause heart valve problems, concerns about its risks are strong enough that an FDA advisory committee last year recommended against its approval.

Because Meridia can cause increases in blood pressure, the FDA recommended that individuals with uncontrolled high blood pressure, heart disease or an irregular heartbeat--as well as patients who have suffered a stroke--not take the drug.

Moreover, the drug should only be prescribed for those who are considered seriously overweight as determined by a body mass index, a formula that involves the relationship of height and weight. Those with a BMI of 30 or higher--with a height of 5 feet 6 inches and weighing 185 pounds, for example--could take the drug, the FDA said.

Patients with a lower BMI, 27 or higher, could also be treated with the drug if they have other risk factors, such as diabetes or hypertension that is under control, the agency said.

In addition, the agency urged all patients on the drug to undergo regular blood pressure screening.

The drug’s manufacturer, Knoll Pharmaceutical Co. of Mount Olive, N.J., stressed that use of the drug will be carefully supervised and prescribed in conjunction with behavior modification programs that include reduced-calorie diets and physical activity.

Company officials said they would provide physicians, state medical boards and weight-loss centers with guidelines on the proper use of the product.

“Obesity is a major public health threat that ranks as the second-leading cause of preventable deaths in the U.S.,” said Carter Eckart, president of the firm. For some people, “losing weight and keeping it off can be a matter of life and death,” he said.

*

“Ultimately, the success of our efforts to direct the use of Meridia to those who can benefit most will be based on the effectiveness of our partnership with prescribing physicians,” he added.

In clinical trials, patients on a reduced-calorie diet who were treated with the drug showed “significant” weight loss during the first six months of treatment, which was maintained for one year, the FDA said.

In a 12-month drug study, the average weight loss for patients who took 10 milligrams a day was about 10 pounds. Patients who took 15 milligrams a day had an average loss of 14 pounds.

This compared to an average loss of 3 1/2 pounds among a control group that was on a reduced calorie diet only.

“My patients tell me that Meridia reduces their appetite so they can make the right nutritional choices and finally stop the yo-yo dieting cycle,” said Dr. David Heber, director of the UCLA Center for Human Nutrition and one of the clinical trial researchers.

“Meridia is an effective tool that makes it easier for patients to comply with a multidimensional program of healthy eating and more physical activity,” he said.

The practical effect on consumers of the DEA involvement in controlling the drug is expected to be slight.

Typically, a drug is included on the list of controlled substances to help prevent abuse or overprescribing.