Sales of the prescription weight loss drug Qsymia, the first such drug to get the FDA's OK in 13 years, are increasing, despite earlier reports of sluggish interest.

For the week ending Dec. 7, more than 2,000 new prescriptions for Qsymia were filled, according to Source Healthcare Analytics, a provider of pharmaceutical market data. That compares to 1,163 filled prescriptions for the week ending Nov. 23.

Depending on who you talk to, the drug, which went on sale in mid-September, is a godsend or a disaster.

Gwen Barton, 57, of New York, participated in a Qsymia clinical trial. She dropped 50 pounds in 18 months. She gained back half of that after the trial ended, then started back on the pill in early December.

The pounds came off again. "I have lost 12 pounds so far and I'm very happy,'' she says. She wants to shed another 40 pounds on her 5-foot-5-inch frame to get to 140 pounds.

Barton offered to share her story through the public relations firm for Vivus, the maker of Qsymia.

When the FDA approved the drug earlier in 2012, Sidney Wolfe, MD, director of Public Citizen's Health Research Group, called the decision ''reckless.''

His opinion hasn't changed, he says. "The history of diet drugs is a disaster," he says.

Qsymia Prescriptions Up

Michael Miller, chief commercial officer at Vivus, declined to release sales figures or quote prescription numbers until January, when fourth quarter results are in.

"We are pleased," he says of sales. "We have been gaining traction."

The drug is only sold through certified mail-order pharmacies whose personnel have finished a Qsymia-provided training program.

That was part of the risk reduction that Vivus agreed to with the FDA.

Average cost of the recommended dose is $160 for a one-month supply, Miller says.

Insurance coverage is not yet common. "About 1 out of 5 prescriptions are covered," he says. "The average co-pay is $50 or $60."

How It Works

Qsymia combines two drugs already on the market: phentermine and topiramate.

Phentermine is an appetite suppressant. (It was the ''phen'' part of the popular weight loss combination pill fen-phen. After reports of lung problems and heart valve damage surfaced, related to the ''fen'' or fenfluramine, the FDA requested fenfluramine's withdrawal from market in 1997).

Topiramate may work by suppressing appetite and helping you feel full, according to the drugmaker.

Qsymia is approved only for those who have a body mass index or BMI of 30+, termed obese, or a BMI of 27+, termed overweight, with another weight-related problem such as high blood pressure or high cholesterol.

It is prescribed with the understanding that patients will follow a healthy, reduced-calorie diet and get regular exercise.

Barton says she walks for exercise. She drinks a lot of water and has given up fatty foods, sodas, and another old favorite, doughnuts.

Thanksgiving was not the struggle it once was. "No seconds, no thirds, I didn't bring food home," she says.

How Well Does It Work?

"In our clinical studies, we found weight loss of up to 10% [over the starting weight] over a year," Miller says. Within the first six weeks, weight losses of 5% occurred, he says.

Qsymia works, says Tim Church, MD, PhD, MPH, professor of preventative medicine at Pennington Biomedical Research Institute at Louisiana State University, Baton Rouge. He was involved in clinical trials and is a consultant for Vivus.

"The most important thing is, it's not a vanity drug," he says. Yet, there are cautions with its use, he says. "The biggest issue with this drug is to keep it out of the hands of women who are trying to get pregnant or who are pregnant.''

Taking it during pregnancy raises the risk for birth defects such as cleft palate.

Other possible side effects are an increased heart rate, suicidal thoughts, and a greater risk of the eye problem glaucoma.

Dissenting Views

In a statement by Public Citizen's Wolfe, issued after the FDA approval, he said: "It is magical and delusional thinking for anyone to believe that a drug will turn off hunger without hitting other targets where it will do harm, usually to the cardiovascular system."

Peter Galier, MD, an internal medicine specialist at the UCLA Medical Center, Santa Monica, Calif., says he has been getting many requests from his patients for Qsymia. Because of its expense, he says, he will sometimes prescribe the two drugs that have been on the market -- topiramate and phentermine -- separately, but in a similar dose.

He also gives them diet and exercise instructions.

Even so, he is not overly impressed. "I have seen weight loss in the first 30-60 days, but then they seem to adjust to both medicines, and the effect wears off. I often [then] see more weight gain than where they started."

When patients start on the drugs, he suggests they take advantage of the appetite-suppressing advantages to focus on changing their diet and starting to exercise. He sees it as an opportunity to get your lifestyle in order.

SOURCES: Tim Church, MD, director of preventive medicine research, Pennington Biomedical Research Center, Baton Rouge, La.Gwen Barton, pharmacy technician, New York.Michael Miller, chief commercial officer, Vivus, Inc., Mountain View, Calif.Peter Galier, MD, internal medicine specialist, UCLA Medical Center, Santa Monica, Calif.Sidney Wolfe, MD, director, Public Citizen's Health Research Group, Washington, D.C.

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